The Syntopix Blog

Speeding up the Transition to Greener Surfactants

2011-03-28T03:47:00.000-07:00

The green trend continues to gain momentum and increasingly consumers base purchasing decisions on perceived health and environmental benefits. This is particularly true in the cosmetic and personal care space where the number of products carrying green claims is on the rise.

The Problem

One key class of ingredients in cosmetics and personal care products is surfactants. Used to create emulsions and microemulsions, surfactants help the water and “oil” components to hold together in stable formulations. There’s clearly a desire to replace conventional surfactants with naturally derived, sustainably sourced or biodegradable alternatives but for the cosmetic scientist the challenge of making this switch in practice is a tough one.

There are very few ways to determine which surfactant is the best green replacement, especially when working with microemulsions. Trial and error takes time, eating into a company’s competitive edge, so it is clear a framework for rational formulation design would be beneficial. Outlined here is a real alternative to the limited Hydrophilic-Lipophilic Balance (HLB) approach.

HLD-NAC Theory

A highly promising approach for identifying key parameters is the Hydrophilic Lipophilic Difference (HLD) - Net Average Curvature (NAC) methodology of Professor Edgar Acosta from the University of Toronto, built on the HLD concept developed by Aubry, Salager, Sabbattini and others. HLD theory is well-established in the oil industry but little-known for cosmetics.

The HLD uses a simple equation based on salt concentration, oil “number” and the surfactant Characteristic curvature (Cc) which identifies the region in surfactant space where the surfactant is most useful. A simple equation determines how close a mixture is to the “optimal formulation” where the smallest amount of surfactant gives the largest amount of (micro) emulsification.

If the Cc of the surfactant is far from this optimum, the emulsion is inefficient/poor. If the Cc is slightly lower than optimum, an efficient type I oil-in-water (o/w) emulsion is produced and if it is slightly higher, an efficient type II water-in-oil (w/o) emulsion is formed.

Importantly, the Cc of a mixture of surfactants is the weighted average of the two. Optimal surfactant mixtures with the desired Cc can be created from combinations of surfactants. Surfactant mixtures are common in cosmetic formulation and HLD theory, uniquely, makes it possible to find optimal mixtures efficiently.

Determining Cc Values

The Cc values are known only for a few dozen surfactants. Catalogues of green surfactants contain hundreds of possible choices but provide no guiding Cc values. Measuring Cc is not very difficult. Take, for example, 8 tubes containing measured amounts of water, surfactant, salt and 8 different oils spanning the appropriate HLD range. Phase transition from w/o to o/w via a type III bi-continuous oil and water emulsion determines the optimal point from which a Cc value can be calculated (see Figure 1).

Figure 1 — Transition from w/o (type II) microemulsions on the left to o/w (type I) microemulsions on the right allows determination of a surfactant’s Cc value. The transition (type III) can be seen in the 5th tube from the left. Phase volumes provide extra information, covered by the NAC part of HLD-NAC theory.

Doing this process for multiple surfactants is tedious, time-consuming and resource-intensive. We therefore developed a quick, efficient and accurate method to determine Cc values of multiple surfactants using a high-throughout screening method.

High-throughput

Specialised high-throughput equipment, such as the Chemspeed Formax, can be utilised to greatly increase processing power. Robotic determination of Cc values can be carried out 4 times faster than by traditional long-hand phase scans, significantly decreasing the required manpower and greatly improving accuracy. This is the first time high-throughput screening and HLD-NAC have been brought together.

Figure 2 – Chemspeed Formax at VLCI, Amsterdam

Cc Values of Green Surfactants

A number of the key surfactant suppliers generously provided a range of green surfactants. They were chosen to cover a large range from hydrophilic to hydrophobic, ionic and non-ionic, ethoxylated and non-ethoxylated, sugar-based, natural extracts, etc. Of the 22 surfactants tested, Cc values were determined for 13 (see Table 1). For the remaining 9, definite values could not be defined within the bounds of this project but minimum or maximum ranges were determined. In general it is desirable to formulate with surfactants with Cc values from -2.5 to 2.5. Within this range surfactants match well to typical oils and formulation conditions. Outside this range surfactants are more difficult to match and therefore not a first choice as a principal ingredient.

Building formulations based on Cc values: the benefits

Using the measured Cc values makes it much easier to get reasonable first approximations to good formulations.

Figure 3 – the free Optimal Surfactant software used for formulation work. Although the HLD-NAC equations are simple, help from software (and the database of Cc values inside it) makes it even easier to use and to understand how to adjust formulations to improve them further. This system provides:

- Improved prediction of surfactant performance in a given formulation;

- Reduced formulation development time, cost and resource;

- Easier selection of appropriate green surfactant alternatives;

- Elimination of surfactant adjustment with alcohols; the fine-tuning of formulations with mixtures of surfactants is possible by calculation of combined Cc value.

As a result of this project, Syntopix Group plc have identified two new green surfactants for incorporation into novel oral care microemulsions.

The Future

All Cc values from the project have been placed in the public domain. In particular, the Optimal Surfactant software (www.stevenabbott.co.uk/HLD-NAC.html) has these values included in its database, allowing users to find their own surfactant formulations. The team has also provided an Instant Guide to HLD-NAC. It is hoped that this project will encourage surfactant suppliers to measure and provide Cc values to aid their customers in formulation design.

Green Surfactant Cc Values

Table 1 - Measured Cc values. Please note that values for surfactants can be source dependent. Values can typically range over +/- 0.2 depending on control of chain length, branching, residual alcohols, salts etc.

The 30 Day Formulation Challenge Project

Supported by Intelligent Formulation Ltd, this was a 30 Day Challenge Project aimed at stimulating innovation in the formulation space. Dr Gavin Donoghue and Sarah Gregory from Syntopix Group plc identified a need for rational microemulsion formulation design. The Challenge brought together two surfactant experts, Prof Edgar Acosta of the University of Toronto (expert in HLD-NAC theory) and Dr Ian Callaghan, an independent consultant. Prof Steven Abbott of the University of Leeds and a consultant to Syntopix provided the Optimal Surfactant software and acted as project leader. Sander Van Loon led the VLCI team running the high-throughput scans. The team thanks David Calvert of Intelligent Formulation for overall coordination of the project.

For further information:

http://www.intelligentformulation.org/

http://www.stevenabbott.co.ukhld-nac.html/

http://vlci.biz/

http://www.syntopix.com/

The Future of Innovation in Biocides?

2011-01-12T02:36:00.000-08:00

By Guest Blogger Dr Jim Bullock, CEO of Intelligent Formulation

It’s pretty difficult to predict the future accurately, but it’s possible to take a systematic look at what factors are driving innovation within particular markets and produce a useful view of how you expect things to develop. This can help to guide your business and strategic decision-making.

At Intelligent Formulation we have carried out a roadmapping and foresighting exercise which covers all of the markets which use formulation technology. In consultation with formulating companies, universities and other organisations we looked at the main global trends and drivers, at what challenges formulators are being asked to undertake, what new tools are or could be available for the formulator and what understanding has been or should be generated.

This exercise helped us identify a number of general challenges for formulation technology, in particular:

Formulation has to be used to improve product performance: ingredients are needed which have “smart” or multiple effects in a formulation; formulations need to be able to deliver an active accurately to a particular site; and formulations are needed which provide novel functionality. Additionally we need to be able to control and manipulate ever more complex multi-component formulations to give the desired effect. There is also a role for novel and cost-effective manufacturing methods to give improved product performance.

As interest grows in sustainable sources, a second challenge is to be able to substitute ingredients in a formulation with those from natural origins. This challenges formulators to maintain or improve the cost-performance ratio of the formulated product whilst working with unfamiliar and poorly characterised ingredients.

Formulation is a great way to introduce new products quickly and cost-effectively, as new effects or improved cost or environmental profiles can be achieved without the need for new molecular entities. But formulations are “complex beasts”. Can we use our understanding of formulated products to do things even better?

In almost every industry where chemicals are used, regulations are a huge driving force. Whether the product is a biocide, an agrochemical, a medicine or a cosmetic, restrictions are growing on how products can be used and what ingredients can be included.

During 2010 we used our general formulation roadmapping exercise to look in more detail at one specific market, namely that for formulated biocides. Looking first at trends and drivers:

Societal trends and drivers have an impact for biocides formulation:

Increased awareness of sustainability leads to a greater use of natural origins and as a consequence the potential for microbial contamination of products increases. Additionally formulators sourcing raw materials need to be aware of changing consumer demand e.g. for Fairtrade in personal care.

A greater societal awareness of water and air quality has led for less environmentally persistent and more biodegradable industrial and consumer products, biocides included.

Society appears to be coming more risk averse and fear driven, over and above legislative demands. This presents biocide formulators with conflicting demands. On the one hand there is an aversion to chemical biocides (“they must be nasty because they kill things”) but on the other hand we are increasingly aware of biosecurity and threats to human and animal health (“I want something that kills things”).

On the other hand changing population demographics opens up opportunities. An ageing population increase the demand for better infection control and healthcare systems. In the developing world a growing middle class increases the demand for enhanced cosmetic and personal care solutions.

Technology also influences and drives the market for formulated biocides:

The demand for fast, lean and flexible manufacture leads industrial users to seek “one size fits all” biocides, and products with easier, less hazardous handling will be sought.

The potential for improved product development methodology may allow the formulator to get more out of existing biocidal actives and additives.

The possibility of product and packaging recycling and re-use also presents challenges and opportunities for the formulator.

Economic drivers are also significant:

“Me too” is no longer good enough in a very competitive marketplace. Are biocide formulators making enough of innovation as a differentiator? Can we think of new ways of making and using biocides? Can we use formulation to develop new products, applications or services?

Production is becoming increasingly globalised. Biocidal active and formulation ingredients are becoming commoditised, but we still want to differentiate our products. Additionally, global product ranges are becoming increasingly common, with one production site serving all markets.

Environmental trends and drivers are increasingly important:

Increasingly the carbon (and water) footprint of products (from raw materials through production and on to end use and disposal) is under scrutiny. Formulators are in a unique central position where they can influence this – with one eye on raw materials and production and the other on the end use and application

Sustainability encompasses the whole product life cycle. Increasing attention is being paid to the consequences (e.g. resistance) of inadequate and unsuitable biocide regimes. Furthermore, there is an increasing look at waste. Active ingredients are expensive: are we formulating in a way to get the most out of our actives?

Finally we looked at political drivers:

In the biocides world we can’t get away from legislation and regulation. Whether it is the EU Biocidal Products Regulation, the US EPA regulations, the EU Cosmetics Directive or the Medical Devices Directive, costs are only going to increase and choice of ingredients will reduce.

Next we looked at the possible conclusions and consequences of these drivers for the world of biocide formulation:

One straightforward conclusion is that the active ingredient is no longer king. This is not only true for biocides (where regulatory drivers have reduced choice and increased the barrier for new actives) but is also being played out in other markets such as pharma and agrochemicals.

Looking at how biocides are currently formulated leads us to a second conclusion – there is a huge potential for improvement. Currently biocides formulations are centred on the efficacy spectrum of one or more active ingredients. We are all familiar with alleged synergy claims between actives; these are usually often nothing more than one biocidal active filling the efficacy gap left by the other. Formulating additives are simply added to give basic physical compatibility with the final product or matrix. There is nothing particularly smart about these formulations

The end result of standard formulations is that active ingredients often go to waste – they are not targeted to the organisms and sites that matter and are degraded along the way. Apart from the potential of underuse leading to tolerance or resistance, the cost-performance ratio has big scope for improvement.

But every problem leads to an opportunity. In a smart formulation the formulation itself is focused on being an effective delivery vehicle for the end application. This means that the formulation targets the active to the right place at the right time using, for instance, encapsulation or triggered release systems. In smart formulations, there is real synergy between ingredients, actives are produced in-situ when you want them and at the right time. All this has the potential to reduce unnecessary human or environmental exposure to active ingredients and to improve cost-performance of the product.

There are real opportunities for biocide formulators to learn from other industries. Smart formulation is being used right now in pharmaceuticals, agrochemicals and personal care applications. Furthermore, formulators can use knowledge from within the supply chain, whether it’s from providers of the actives and additives or from the end users. Biocides formulation has the reputation of being a bit secretive. Perhaps it’s time for a change?

So our conclusion leads us to a pretty simple set of final messages to biocides formulators. If you want to generate value in the biocides industry, don’t just concentrate on the active; use smart formulation to get more value out of your product. Be prepared to collaborate on ideas with partners in your own supply chain and be prepared to collaborate with and learn from other formulating industries. Usually they are not your competitors, so commercial success through partnership and knowledge exchange is a real possibility.

At Intelligent Formulation we are dedicated to helping companies like Syntopix become more successful by innovating in formulation. Have a look at our website, blog, LinkedIn group or Twitter feed to see how we are doing just that.

Intelligent Formulation are currently supporting a Syntopix research project through the '30 day formulation challenge' scheme.

Skin, bacteria and mobile ‘phones: making the right call

2010-12-06T04:23:00.000-08:00

By Sarah Gregory, Dr Steven Jones and Prof. Steven Abbott

Syntopix recently presented at the Intelligent Formulation event “Formulated Product Design: Kick Starting Open Innovation”. It was a great event and a brilliant way for small businesses like ours working on innovative formulation approaches to connect with potential partners.

For those unable to attend, the main points of the presentation given by Dr. Steve Jones, CEO of Syntopix and Prof. Steven Abbott, Independent Consultant, are summarised below.

Formed in 2003, Syntopix is a spin out from Leeds University and was listed on AiM in 2006. With a rich portfolio of new product opportunities Syntopix offers antimicrobial expertise to the cosmetic, consumer healthcare and pharmaceutical industries.

Driven by high rates of skin irritation, increasing bacterial resistance and environmental concerns over current treatments, Syntopix began the search for new active ingredients capable of really clearing up acne without any of the downsides.

It soon became apparent that selecting the right antimicrobial was just the first step. To be really effective on skin we needed to tackle formulation head-on to deliver the active directly to where the spot-causing bacteria live, the follicle.

Traditional approaches were tried but we couldn’t replicate our excellent lab results when we tried human volunteer studies. It was time to “phone a friend” to find a fresh answer to our problems. As a result of a chance meeting, Syntopix discovered Professor Steven Abbott, a polymer chemist and software developer, who, amongst other things, had been developing protective coating for mobile phones. Whilst not at first glance the formulation consultant we were looking for, Steven’s approach to our problem started to give the results we needed: how to kill off P. acnes within the follicle at a low concentration of active.

Professor Abbott’s approach involved harnessing Hanson Solubility Parameters to match the solubility of our formulation and the active to that of skin. His basic assumption (anathema to the classical skin permeation world) was that skin was “just a polymer” so the science that worked well for, say, coatings onto mobile phones would also be effective on skin. And it did work! Steven happily pronounced that the skin permeation world has been wrong for the past 20 years.

Our selected active, a cosmetic ingredient known to be safe and naturally derived, produced a 90% mean reduction in acne-causing bacteria after 4 days. These results, comparable to the bacterial kill rates of antibiotics, are unrivalled by current cosmetic spot products.

Since then we have demonstrated that this platform formulation technology works for other anti-acne actives. By targeting delivery directly to where it’s needed, the approach reduces waste and speeds up the time taken to see results. It’s cheap, simple (i.e. has few ingredients) and effective.

It’s also apparent that this formulation approach will have applications beyond acne. With the ability to enhance substantivity within the top layer of the skin (the stratum corneum), we are confident this platform will allow deodorants to work for longer. Targeted follicular delivery via the pore is desirable for products such as depilatories, and hair stimulants. Getting the active to where it’s needed quickly and without waste leads to a host of new or improved products that will reduce cost and allow consumers to see the results they desire in less time.

Our lessons have been many and we’ve experimented more than just in the lab. We have had the nerve to bring two different worlds together and the courage to challenge assumptions - now we have a novel approach for delivery to the skin. Syntopix was founded on an unwavering desire to truly improve the way people look and feel, and we believe this technology has the capability to do just that.

Syntopix is actively seeking to expand its range of commercial partnerships to take this exciting technology forward. Please contact us with your business development enquiries. We look forward to hearing from you.

W: www.syntopix.com
E: spj@syntopix.com
T: 0845 125 9204

Formulation guided by Hansen Solubility Parameters and realized via High Throughput Screening

2010-11-02T05:41:00.000-07:00

By Sarah Gregory

Syntopix recently attended an Intelligent Formulation event on how to use high throughput screening to accelerate formulation development at which we presented a poster.

The poster summarises how Hansen Solubility Parameters can be used to develop topical formulations and how the process can be automated to efficiently translate concepts into prototype formulations.

Excerpts from the poster by Professor Steven Abbott, Dr. Gavin Donoghue and Dr. Anne Eady are below:

The Problem

Formulating for delivery of actives into skin requires multiple compromises. The active has to be soluble in the delivery “chassis”, and the chassis needs to solubilise the correct part of the skin in order to aid the permeation of the active. At the same time, the solvents/excipients in the chassis have to meet strict regulatory guidelines. Almost inevitably this requires a complex mixture and the solubility characteristics of the mixture need to be known in order to be optimized. Without rational formulation guidelines, this task is often hit-and-miss, using simplistic and misleading terms such as “hydrophilic” or “lipophilic”, which don’t do justice to the complexity of chemical space. Syntopix develops novel antimicrobials for the management of acne prone skin. The company was seeking a method of rational formulation design in order to ensure efficient delivery to the target site.

Understanding solubility characteristics

One proven, powerful method for understanding solubility is the use of Hansen Solubility Parameters. These 3 values provide a means of predicting whether one material will dissolve in another and form a solution:

δD represents the energy from dispersion bonds

δP represents the energy from dipolar intermolecular forces

δH represents the energy from hydrogen bonds

The HSP of a mixture is simply the weighted average of the individual components. Using HSPs, it is possible to make a solvent from two non-solvents. Syntopix has exploited this approach to devise solvent mixtures for difficult to solubilise actives.

To view the full poster, please click here.

The FDA OTC Acne Monograph – stifling the development of better treatments?

2010-07-30T01:45:00.000-07:00

By Dr Anne Eady

In my personal view the biggest single barrier to the development of better therapies for acne is the 20 year old FDA OTC Acne Monograph. Here I’ll explain why I believe this regulatory document is stifling much needed innovation in the management of this very common skin condition.

Acne is unusual in that remedies fall into two regulatory classes, medicines and cosmetics (although these cannot be sold as acne remedies but rather as products to manage ‘breakouts’). Teenagers and their parents aren’t generally aware of this and find it hard to discriminate between product intended to manage a few pimples and those required to treat more severe disease. In most countries including the US and the UK, the OTC segment is the first port of call for acne sufferers for whom cosmetic products haven’t worked. Here I will use the term ‘acne’ to refer both to the disease and to the cosmetic indication of ‘spots’.

Acne is easily self-diagnosable and therefore amenable to self-selection of treatment. Moreover pressure in the US, UK and elsewhere on healthcare budgets, means that OTC route is likely to become even more important in the future than it is now as the main conduit via which acne sufferers access treatment. The emerging role of pharmacists in the management of easily diagnosed conditions like acne further focuses attention on the OTC route. Seeking help from a medical practitioner could and should become a strategy of last resort.

So where is the problem? There is an urgent need for innovative treatments for acne that can be made available via non-prescription routes. People with acne don’t want to take antibiotics for months or years at a time and antibiotics are not a suitable therapy for a chronic condition like acne. In the community, antibiotics for acne are a significant driver of antibiotic resistance which is a communicable adverse treatment effect. Benzoyl peroxide (BPO) and topical retinoids offer alternatives to antibiotics but neither is problem free. BPO is the oldest topical treatment for acne and has been around for over 50 years. It works well but it bleaches everything with which it comes into contact. Modern formulations have done much to reduce irritancy in all but highly susceptible individuals or those who tend to be over-zealous in the amounts they apply. Topical retinoids are still underused and offer an equally effective alternative to BPO. Whilst BPO is available without a prescription, topical retinoids are not. In the future, they might be re-classified as long as regulators can be persuaded that the risk of teratogenicity is infinitely small.

In the US, over-the-counter acne medicines are regulated by the FDA via the monograph system. So, what else is permitted in the OTC space? The answer is very little that anyone nowadays would choose to use – would you want to put sulphur or resorcinol on your skin? The FDA monograph is backward looking and yet it still influences OTC availability of acne treatments within and beyond the US. Apart from BPO, the only other OTC listed active that can be said to demonstrate efficacy is salicylic acid, another very old remedy. Salicylic acid, in the concentrations permitted, is not a very effective treatment for those with anything other than mild, ‘cosmetic’ acne. Unlike BPO, for which evidence of efficacy is overwhelming, published reports of its efficacy are few and far between and not very convincing.

I’m sure these criticisms apply across the FDA Monograph system and don’t just apply to acne. The OTC sector should drive not stifle innovation. It is the obvious regulatory space for new products to treat diseases like acne. Cosmetic companies are much more innovative than big pharma and yet can only go so far given that cosmetics cannot be seen to treat disease and acne is a disease. However, the spectrum of severity of acne is wide, onset is typically slow and prevention is surely better than cure. So if a cosmetic product can be said to enhance the appearance of skin by keeping it blemish-free then, in theory at least, it could work as well as any medicine. Assuming that there will always be a big demand for treatments as well as prophylactics, new medicinal products containing new actives will be required. Most existing topical acne therapies produce at best a 50-60% reduction in lesions after weeks or months. There is still much room for improvement despite the advances in formulation technology that have allowed the development of combinations products based on BPO and an antibiotic, a retinoid and an antibiotic or more recently BPO and a retinoid. This is still just playing around with old molecules when what are urgently required are entirely new actives that can be sold OTC. If we really want to relieve the burden on physicians, reduce reliance on antibiotics and put control in patients’/consumers’ hands, we have to give them choice and we have to provide effective new remedies that overcome the disadvantages of the older ones.

I’d like to see either a complete overhaul of the FDA OTC Acne Monograph or preferably its abandonment and I’d like to see it sooner rather than later. It is worth mentioning that the final FDA rule on BPO was only published in March of this year. This is hardly indicative of a responsive regulatory process. The FDA has led the way with tighter controls on the availability of oral isotretinoin and yet none of the available alternatives come even close to the power of this agent. Isn’t it about time that regulators facilitated the development of safer, more effective treatments? Without the constraints imposed by the monograph, I’m sure big pharma and major healthcare companies will respond rapidly to the challenge of overcoming conservatism and competing successfully with the more innovative cosmetic sector.

References

1. Food and Drug Administration. Topical Acne Drug Products for Over-The-Counter Human Use: Final Monograph. Federal Register 1991; 56 (159): 41008 – 41020.

2. Food and Drug Administration. Classification of Benzoyl Peroxide as Safe and Effective and Revision of Labeling to Drug Facts Format; Topical Acne Drug Products for Over-The-Counter Human Use; Final Rule. Federal Register 2010; 75 942): 9767-9777.

3. Patel M, Bowe WP, Heughebaert C, Shalita AR. The development of antimicrobial resistance due to the antibiotic treatment of acne vulgaris: a review. J Drugs Dermatol 2010; 9(6): 655-664.

4. Seidler EM, Kimball AB. Meta-analysis comparing efficacy of benzoyl peroxide, clindamycin, benzoyl peroxide with salicylic acid, and combination benzoyl peroxide/clindamycin in acne. J Am Acad Dermatol 2010; 63 (1): 52-62.

Syntopix to present TBHQ data at ICAAC 2010

2010-06-18T06:38:00.000-07:00

By Sarah Gregory

Syntopix has joined forces with the University of Leeds to conduct a research project into the antibacterial activity and mechanism of action of the lipophilic antioxidant tert-butylhydroquinone (TBHQ).

Working with Professor Ian Chopra, Dr Nicki Ooi, and Dr Alex O’Neill, the Research and Scientific Directors of Syntopix Dr Jon Cove and Dr Anne Eady are looking to investigate the compounds antimicrobial mode of action.

Research results will be published in a poster publication later this year at the 50th Interscience Conference on Antimicrobial Agents and Chemotherapy meeting which is taking place between the 12 Sept – 15 Sept 2010 in Boston, USA.

For further details please click here.

Finding a partner for your great idea: how do your get their attention?

2010-06-16T07:04:00.000-07:00

By Dr Stephen Jones

When you’ve got a great idea which you’re convinced will make you money, you have to sell it. Identification of the right partner, and finding enough common ground to do the deal, is far from easy. There are so many doors to knock on; lots of companies, each with an array of decision-makers. So where do you start?

In my experience, finding doors to knock on is the easy bit. The tricky part is making sure it’s the right door for you if they open it. Then, if you’re invited in, it’s knowing what to say, and what you are looking for.

I’ve stood on both sides of this particular fence. Before I joined Syntopix in 2006, I was for 7 years Vice-President of R&D at GlaxoSmithKline Consumer Healthcare, responsible for all the R&D projects to support Aquafresh, an oral healthcare brand with global sales approaching $1 billion. A constant stream of small companies (like Syntopix) from all over the world would contact us with (in their eyes) the most fantastic ideas and superb technology. It wasn’t easy to spot the winners and all too easy to be misled by the cowboys. One of the most successful innovations in my time at GSK was a collaboration with an external company which resulted in a product called “Aquafresh White Trays” for whitening teeth. Right from the very first meeting they were very clear about what they wanted and they showed that they were obviously experts in their field.

At Syntopix we are developing compounds to incorporate into products for treating acne and body odour, and improving oral healthcare. Now we have promising candidates, we are looking for commercial partners who will licence our technology. Knowing what a good pitch looks like from a large company’s perspective has been enormously helpful in shaping our business development approach.

I’ve always found that being very clear about your expectations and what you have to offer right at the outset is the route most likely to lead to success. When you make a presentation, it always helps to start by telling your audience (most of whom you will never have met before) what you want from the meeting and why you are there. Don’t make it complicated – the simpler the better. If you want to get them on your side, the easier you make it for them to understand what you want, the more likely you are to succeed.

Similar rules apply to the technology or science that you are presenting to them. The objective of the meeting is not for you to look good or clever, but to be believable. You have to succinctly convince them that you have a unique offering which can enhance their business, and you know what you are talking about. Credibility is absolutely key, which is why it is such an advantage to Syntopix to have co-founders who are world experts in their field (Anne Eady and Jon Cove).

If you can demonstrate the use of your technology in the business setting of the audience, so much the better – it’s hard work to get it right, but your vision and empathy with their world is normally very much appreciated. Showing you can listen to what they need and you think in the same way as them usually helps to make you stand out.

I know from hard experience that your audience will have to spend time and energy understanding your presentation if they are to seek approval from within their own company to take things forward, so make sure you give them what they need, and don’t over-burden them with superfluous facts that aren’t central to your objectives.

Finally, it’s easy to commit two more sins that can be deal breakers because they irritate people and lose their attention. Don’t take any more time than you are allotted (finishing early is always appreciated), and don’t try to cram 60 slides into a 30 minute presentation. The more senior the audience, the more important it is to follow these last two bits of advice.

We’ve been knocking on lots of doors recently and presentations have become a way of life for Syntopix. Pitching your big idea can’t be left to luck. Practice makes perfect, and as Arnold Palmer once said, the more you practice, the luckier you get.

Is skin a poor polymer?

2010-04-28T01:45:00.000-07:00

By Guest Blogger Professor Steven Abbott

My experience in life is that the best things happen by accident. That’s how I got to know Syntopix. We met through my role as a Visiting Professor at the University of Leeds where I do work on nanofluidics and biomimetic structures. The initial discussions were interesting but for various reasons led to nothing. However, I happened to mention that I thought that the basic model of how skin permeation works was fundamentally wrong and that as a chemist I see skin as a rather poor barrier whose diffusion properties are best explained via classical polymer diffusion. Now most cultures resent ignorant outsiders expressing such wild opinions. But Syntopix called my bluff. “OK”, they said, “let’s see if your ideas stack up against the real world”.

6 months later we’re still working together. And it’s been a huge learning experience for both sides. I remain convinced that the “skin as a poor polymer” analogy is very helpful. Using my expertise in Hansen Solubility Parameters and applying them to skin in the same way that I apply them to other important barrier issues (e.g. the right choice of gloves for protection against chemicals) we seem to be creating fecund formulating hypotheses. On the other hand, whilst it’s OK for me to say as a chemist “use chemicals X, Y and Z in this formulation” I’ve had to have a crash course in how (rightly) restrictive the rules are for chemicals that are going to go on human skin – and that’s before starting on issues like looking, feeling and smelling good when applied in the real world. There is a vast area of expertise out there required before any mere chemist’s suggestion can become a real product.

And although I say that skin is a poor polymer I mean this only in the sense that its barrier properties are rubbish compared to a real polymer such as polyethylene or PET. What I’ve learned, of course, is that although it’s rubbish as an absolute barrier, it’s astoundingly smart in being the barrier that it needs to be – not too good and not too bad. And it can easily outsmart the formulation plans of people like me. But then if it were easy, the solutions would have been spotted long ago.

Of the many things I’ve learned working with Syntopix, one is the value of supporting each other as a team – even an outsider such as myself. When my first suggested formulation was an utter failure, I’d assumed I’d be kicked out of the door. But the Syntopix team assured me that the chances of anyone’s first formulation actually going straight to the target organism and specifically zapping it in a week were effectively zero. For all we knew, my part of the equation had worked wonderfully (with further work we now understand it’s fatal flaws!) and the bugs simply were refusing to cooperate. So they stuck with me.

But that required another side to Syntopix. From time to time I’m hauled in for a session entitled “Give me 10 good reasons why your ideas aren’t rubbish”. The team throw everything they can at me, and ask me to be just as critical of myself. These sessions are crucial to our working relationship. The aim is to end the session agreeing that idea X really is rubbish, idea Y has stood up to the test and, importantly, idea Z had a fatal flaw (see my previous paragraph) which we can readily fix. Syntopix is a relatively small company so its resources are precious. It cannot afford to waste them on dumb ideas. So we work together to decide which ideas really are dumb, so we can focus on the good ones. These “negative” sessions generally work out to be the most positive meetings of all. The fix we found for the fatal flaw seems to lead to all sorts of interesting possibilities – which would never have occurred to me if the team had not spotted the flaw in the first place.

Will I help them find a blockbuster product? I hope so – there are plenty of encouraging signs. But if success does come, it will only be because this extraordinary Syntopix team has worked so effectively to take my contribution and weave the other magic around it.

On the scent trail - Deodorant specificity

2010-04-13T01:29:00.000-07:00

By Dr Nicholas Read

The axillae, or “underarms” as they are more commonly known, are often associated with the problem of body odour. There are several reasons why this is the case but one of the main causative factors is the large number of eccrine, apoeccrine and apocrine sweat glands found in this region of the body (Wilke et al. 2007). The apocrine sweat glands appear to be especially important (Troccaz et al. 2004). These glands open onto the hair canal and secrete an oily substance containing proteins, lipids and steroids (Wilke et al. 2007). The fluid secreted by the apocrine glands is initially odourless but includes a number of odour precursors (Troccaz et al. 2009). These precursors are converted into odorous compounds such as the steroidal compound 5-α-androst-16-en-3-one, the fatty acid (R)/(S)-3-hydroxy-3-methylhexanoic acid and the thiol 3-methyl 1-3-sulfanylhexan-1-ol (Decreau et al. 2003; Troccaz et al. 2009). The conversion of the odour precursors is mediated by the action of micro-organisms that are found within the axilla (Decreau et al. 2003).

Microflora of the underarm
The human axilla supports one of the highest densities of micro-organisms found on the surface of the skin (Jackman and Noble, 1983). The precise composition of the micro-organisms varies from one individual to another, though in general consists of staphylococci, micrococci, propionibacteria, aerobic coryneforms and the yeast genus Malessezia (Taylor et al. 2003). Analysis of odour production has revealed that different micro-organisms contribute to odour levels to varying degrees. Results indicate that there is a strong correlation between odour levels and aerobic coryneforms (Taylor et al. 2003; Rennie et al. 1991). Of these aerobic corynebacteria it appears that those with the ability to metabolise free fatty acids make the most significant contribution to odour production, whereas the non-free fatty acid metabolising corynebacteria make little or no contribution (Austin and Ellis, 2003; James et al. 2004).

Scattergun or direct hit?
Despite there being only certain strains of bacteria within the axilla that make a significant contribution to body odour, the deodorants currently on the market tend to contain rather unspecific antimicrobials such as ethanol, cosmocil and triclosan. These antimicrobials reduce the total number of underarm bacteria, including many of the non-odour-producing bacteria which it may be beneficial to keep.

There is therefore potential for the development of deodorants containing compounds which specifically target odour-producing bacteria, and leave the non-odour-producing bacteria alone. Possible approaches in the future may include the use of compounds which stop or reduce the metabolism of the odour-producing bacteria through inhibition of key enzymes. Enzymes to target may include the zinc-dependent aminoacyclase and C-S lyase described by Natsch et al. (2004), both of which have been shown to be involved in the release of odoriferous compounds from odourless axilla secretions. Other approaches may be to target the odour-producing bacteria through the use of antibodies raised against the odour producers (Casey et al. 2001) or through the limitation of nutrients specifically required by the odour producers (Landa and Makin, 2003).

Given that there is some evidence that cocci and corynebacteria are able to antagonise or outgrow each other (Jackman and Noble, 1983), it is probable that the competition from the non-odour formers will slow the re-establishment of the odour formers long after the antimicrobial is still active. From this it is possible that a more targeted antimicrobial approach may lead to a more sustained deodorising effect. Such an effect would clearly be attractive as it would have the potential to improve upon the performance of the deodorants currently on the market.

References

Wilke K., Martin A., Terstegen L. and Biel S. (2007) A short history of sweat gland biology. International Journal of Cosmetic Science 29, 169-179

Troccaz M., Starkenmann C., Niclass Y., van de Waal M. and Clark AJ. (2004) 3-methyl-3-sulfanylhexan-1-ol as a major descriptor for the human axilla-sweat odour profile. Chemistry and Biodiversity 1, 1022-1035

Troccaz M, Borchard G, Vuilleumier C, Raviot-Derrien S, Niclass Y, Beccucci S and Starkenmann C. (2009) Gender specific differences between the concentrations of non-volatile (R)/(S)-3-methyl-3-sulfanyl-1-ol and (R)/(S)-3-Hydroxy-3-methyl-hexanoic acid odor precursors in axillary secretions. Chemical Senses, advance access 1-7

Decréau RA, Marson CM, Smith KE, and Behan JM. (2003) Production of malodorous steroids from androsta-5,16-dienes and androsta-4, 16-dienes by Corynebacteria and other human axillary bacteria. Journal of Steroid Biochemistry and Molecular Biology 87, 327-336

Jackman PJH and Noble WC. (1983) Normal axillary skin microflora in various populations. Clinical and Experimental Dermatology 8, 259-268

Taylor D, Daulby A, Grimshaw S, James G, Mercer J. and Vaziri S (2003) Characterisation of the microflora of the human axilla. International Journal of Cosmetic Science 25, 137-145

Rennie PJ, Gower DB and Holland KT (1991) In-vitro and in-vivo studies of human axillary odour and the cutaneous microflora. British Journal of Dermatology 124, 596-602

Austin C and Ellis J (2003) Microbial pathways leading to steroidal malodour in the axilla. Journal of Steroid Biochemistry and Molecular Biology 87, 105-110

James AG, Casey J, Hyliands D and Mycock G (2004) Fatty acid metabolism by cutaneous bacteria and its role in axillary malodour. World Journal of Microbiology and Biotechnology 20, 787-793

Natsch A, Schmid J and Flachsmann F (2004) Identification of odoriferous sulfanylalkanols in human axilla secretions and their formation through cleavage of cysteine precursors by a C-S lyase isolated from axilla bacteria. Chemistry and Biodiversity 1, 1058-1072

Casey et al. (2001) United States Patent US 6,171,582 BI Method for preventing or reducing malodour

Landa AS and Makin SA (2003) Iron sequestration on skin: a new route to improved deodorancy. International Journal of Cosmetic Science 25, 127-135

If you’re not living on the edge…

2010-02-22T03:04:00.000-08:00

By Sarah Gregory & Dr Anne Eady

It’s looking like trialling cosmetics in the same way as a drug is the vogue way to give your product competitive edge.

Procter & Gamble is the latest company to undertake a clinical study with one of their anti-wrinkle products that is comparable to tests undertaken by drug companies. The results, published in the scientifically respected British Journal of Dermatology, are impressive showing that the cosmetic product reduces wrinkles to the same extent as a prescription medicine.

There is little doubt that consumers are willing to place their belief in products which are scientifically proven. The Protect & Prefect range at Boots saw huge increases in sales after peer review publication of clinical trial data demonstrating efficacy. This shift in expectation can only be good for both the end user and the industry but are things really that straight forward?

Performing a study on a cosmetic product to the rigour of a medicinal trial is clearly good practice and is to be encouraged. However, many drug trials are badly designed and their results unreliable. Simply doing a drug-type trial on a cosmetic shouldn’t be taken by journalists or the public as an indication of quality or efficacy.

The study performed by Procter and Gamble was not only a good quality trial but also one in which the control arm was a medicinal (drug) product. It was a medicinal trial because it had to be – drugs cannot be compared with cosmetics in a trial performed under the cosmetic regulations. What this high quality trial showed was that a three component cosmetic regimen, of which one component was a retinoid, was at least as effective as a single component prescription product containing a different retinoid. The efficacy of the three component regimen cannot be attributed to the retinoid component. If consumers want to know whether the retinoid available as a cosmetic is as good on its own as the retinoid available on prescription, then another study is required to answer this.

A close call
Wrinkles, the target of the Procter and Gamble product are not a medical indication but a cosmetic one. The company very carefully chose to prove the biological effectiveness of their product by looking at markers of efficacy that lie in the dead cells of the stratum corneum not in the living skin. Thus they have shown that a cosmetic regimen is as good as a prescription medicine but not that the cosmetic works in a pharmacological way that qualifies it for drug status.

More generally, by comparing a cosmetic product with one only available on prescription there is a very real danger of blurring a regulatory line which is already hard to define. A recent New Scientist article gave an overview of some issues which are already muddying the line between cosmetics and medicines and in particular it discusses the Procter and Gamble study.

The New Scientist article points out that if a cosmetic works as well as medicine it could be viewed as a drug in Europe. If cosmetics begin to be tested as drugs and are shown in drug-type trials to be as good as drugs (even if a drug is not included as a comparator), this very finding may challenge their regulatory status as cosmetics.

This increasing regulatory complexity will no doubt be tested over the coming years. Until then exactly what can be claimed by cosmetic products even after they have successfully undergone rigours scientific testing may be a tough judgement call.

Cash to splash
Another issue will almost certainly be the cost of running medicinal quality human use studies with products intended for cosmetic use.

Until now very few cosmetics have been clinically compared to pharmaceuticals or evaluated in randomised controlled trials (RCTs), the gold standard of efficacy testing. Making cosmetic trials as good as pharmaceutical trials can happen without changing the regulatory status of cosmetic products. As long as the comparator is not a medicine, there is no reason why excellent quality studies cannot be performed on cosmetics under the cosmetic regulations. However, RCTs of medicinal quality are costly to set up and run.

In an industry which is largely self-regulated are there many cosmetic companies who would be willing to brave industry regulation at its toughest? Pharmaceutical regulation is notoriously challenging and expensive. Surely there are few cosmetic companies with pockets deep enough to compete on this level?

References

Fu JJJ, Hillebrand GG, Li J, Marmor MJ, Bertucci V, Grimes PE, Mandy SH, Perez MI, Weinkle SH, Kaczvinsky JR. A randomized, controlled comparative study of the wrinkle reduction benefits of a cosmetic niacinamide⁄peptide⁄retinyl propionate product regimen vs. a prescription 0Æ02% tretinoin product regimen. Br J Dermatol. 2010 Feb; 162: 647-654.

Pitman S. Boots beauty sales driven by latest Protect & Perfect launch. Cosmetic Design Europe. Nov 2009.

Watson RE, Ogden S, Cotterell LF, Bowden JJ, Bastrilles JY, Long SP, Griffiths CE. Effects of a cosmetic 'anti-ageing' product improves photoaged skin. Br J Dermatol. 2009 Aug;161(2):419-26.

Geddes L. Anti-ageing cream as good as drug at reducing wrinkles. New Scientist. Feb 2010.

The Alchemists’ Assistant

2010-01-28T00:59:00.000-08:00

By Diane Brear

I remember my interview for the post of Office Manager at Syntopix very clearly. I’d done my homework on the company but there was a potential problem which made me wonder whether it was the job for me; a pharmaceutical research company would be run by scientists and, more critically, have laboratories full of “bugs” and chemicals.

My overriding memories of science at school were of constantly worrying about being poisoned or blowing myself up. As a result, I left the world of test-tubes and Bunsen burners behind me at the age of 16 with more than a sigh of relief. And as a life-long hypochondriac, how would I cope? My husband joked that if I did get the job, I would have to request a full protective suit and breathing apparatus…

Then there were the scientists themselves. I had worked with engineers, salesmen, civil servants and web designers. I was used to the radio-accompanied, creative and spontaneous world of media people and the go-get-it, chatty approach of salesmen. What would it be like to work with studious, academic types in white coats?

But I needed the job. So it was that, at interview, I was offered a tour of the labs! My pulse raced; stickers on the lab doors scarily warned of “Biohazards”. Looking through the window, I could see neatly stacked agar plates containing goodness knows what, about to be screened by the white-coated scientists wearing safety glasses and blue protective gloves. Outside I took a deep breath, politely bobbed my head in and took a cursory look round. “Impressive,” I uttered, as I withdrew back outside and started to breathe again.

I think I managed to disguise my fears because they offered me the job! Despite my doubts, there was something in the enthusiasm and professionalism of the people I met that persuaded me it was worth trying to overcome my fears.

And so began my therapy! With the help of my scientific colleagues, I have fought my demons and can now actually breathe whilst passing on a message to someone working in the lab! I now know that everything is strictly controlled and safety is paramount. I have learned to assess risk and keep things in perspective.

And what is it like to work with a team of scientists (and be the only member of the team who isn’t one)? Well, I have to report that scientists are pretty much like most other human beings I have worked with. They have a great work ethic, are focused, enjoy what they do (understatement!) and have a great sense of humour. I am intrigued by their constant curiosity and questioning and their ability to constantly bounce back if results are not encouraging. And I am envious of their confidence to experiment and think outside the box. It strikes me that the knowledge they have gained through years of study of how the natural world operates empowers them to go through life with a balanced and healthy attitude, free from the daily anxieties I constantly seem to dream up in ignorance. (Or maybe these attributes were already there and are what made them enter the world of science in the first place?)

But they also have some unique qualities which have sometimes caught me by surprise. For instance, last year I was checked out for MRSA prior to a minor operation in hospital. On learning of this, a colleague offered some sympathy for the prodding and poking I had endured, but was quick to request a sample if I proved positive!

Hey-ho! I now feel part of the team and I share their excitement if I spot them round the microscope. They are amazingly organised and structured in their work, producing colour-coded tables and graphs in abundance. Their lab books are as much a piece of art as any web page. And there is still something endearing seeing the Alchemist inside them, searching out that elusive philosopher’s stone….

Do R&D cuts really mean in-licence boom?

2010-01-22T03:08:00.000-08:00

By Sarah Gregory

For all those in small R&D companies there is some good news from the analysts at Morgan Stanley. In a major report just issued they say that the pharma sector offers a good investment opportunity at the moment as large companies step up to the changing face of drug development.

With poor returns from the last 10 years of research, companies such as AstraZeneca and Sanofi-Aventis are leading the way in externalising research as a solution to pipeline gaps. AstraZeneca for example is reallocating up to $1 billion a year to in-licensed assets.

So with money apparently burning a hole in their pockets does this mean that small R&D companies will see an increase in the chance of a deal?

Developing new drugs is risky and there is no doubt that small companies can be more agile. Decisions can be taken quickly and issues can be dealt with on the spot. The trouble is that it takes an awful lot of cash to reach phase II, traditionally the point at which large pharma sit up and listen. Hopefully the move towards utilising external research will stimulate a need and willingness to in-licence at an earlier stage, something the dermatology sector could definitely benefit from.

For a good summary of the Morgan Stanley report please see this Pharma Times article.

Resveratrol: exciting anti-acne?

2009-11-27T04:19:00.000-08:00

In response to the last Syntopix blog post (Acne: deficit of CD14+ mononuclear cells leaves inflammation unchecked), we were asked about our thoughts on the recent resveratrol acne study.

The reply from Dr Anne Eady can be seen below.

The paper by Docherty et al (J Antimicrob Chemother 2007; 59: 1182-4) showed that resveratrol was active against P. acnes but only at relatively high concentrations (IC50 >50 mg/L). Had they used benzoyl peroxide as a control for their tests on bactericidal activity, they would have seen what a really good bactericide can do. Even if we assume bacteriostatic activity could be sufficient, then the comparison with erythromycin becomes relevant and again the low potency of resveratol against P. acnes is revealed. I do not believe it would be possible to deliver supra-inhibitory amount of drug the infundibula of pilosebaceous follicles where P. acnes resides by the topical or oral route.

Having said that, resveratrol still appears to be a good anti-acne candidate because its anti-inflammatory and antioxidant activities are both relevant to acne pathogenesis. In reference to IL-10, resveratol has been shown to up-regulate production of this cytokine by LPS-stimulated macrophages (Sharma et al 2006; 147: 155-63) but only 2 fold at a concentration of 4.4 mg/L (20 mM). Resveratrol has also been found to decrease the IFN-g/IL-10 ratio in murine splenocytes at 0.2 mg/L (1 mM) suggesting it may be able to shift the Th1/Th2 balance in acne towards an anti-inflammatory (Th2) mediated response (Rachon et al. Phytomedicine 2006; 13: 419-24). Last but not least, resveratrol down-regulates the expression of co-stimulatory molecules on macrophages (Sharma et al, vide supra) but again at higher than pharmacologically achievable concentrations.

We are therefore left with the possibility that resveratrol can work in acne via its ability to inhibit lipid peroxidation. The IC50 value for inhibition of peroxidation of phospatidylcholine liposomes by resveratol was estimated at 0.1 mg/L whereas peroxidation of linoleic acid (deficient in acne) was inhibited by over 60% at 0.4 mg/L (Tadolini et al. Free Rad Res 2000; 33: 105-14 and Fabris et al. Biophys Chem 2008; 135: 76-83). Significantly, resveratrol does not scavenge singlet oxygen, the main mediator of squalene peroxidation in skin.

In summary, resveratrol has an exciting anti-acne activity profile but none of the biological effects of relevance (including induction of IL-10) are likely to be manifest at concentrations achievable in vivo.

Further reading:

Docherty JJ, McEwen HA, Sweet TJ, Bailey E, Booth TD. Resveratrol inhibition of Propionibacterium acnes. J Antimicrob Chemother. 2007 Jun;59(6):1182-4. Epub 2007 Apr 21.

Rachoń D, Rimoldi G, Wuttke W. In vitro effects of genistein and resveratrol on the production of interferon-gamma (IFNgamma) and interleukin-10 (IL-10) by stimulated murine splenocytes. Phytomedicine. 2006 Jun;13(6):419-24. Epub 2005 Nov 15.

Tadolini B, Juliano C, Piu L, Franconi F, Cabrini L. Resveratrol inhibition of lipid peroxidation. Free Radic Res. 2000 Jul;33(1):105-14.

Fabris S, Momo F, Ravagnan G, Stevanato R. Antioxidant properties of resveratrol and piceid on lipid peroxidation in micelles and monolamellar liposomes. Biophys Chem. 2008 Jun;135(1-3):76-83. Epub 2008 Mar 29.

Acne: deficit of CD14+ mononuclear cells leaves inflammation unchecked

2009-11-20T03:28:00.000-08:00

A recent publication in the British Journal of Dermatology investigated the immune reactivity of patients with acne compared with healthy controls. By examining the response of peripheral blood mononuclear cells (PBMCs) to stimulation with P. acnes the study looked at levels of interleukin (IL)-10, which has an established immunoregulatory role in inflammatory disorders such as acne. The commentary below is from one of the authors.

By Dr Anne Eady

After decades of research, we know a great deal about late events in acne lesion formation. Once visible inflammation is present, multiple inflammatory cascades have already been set in motion and it is difficult, if not impossible to determine, which event came first. When papules and pustules are days old, there is very little to distinguish acne from other types of chronic inflammation associated with delayed-type hypersensitivity responses to persistent immunogens.

In order to develop better treatments for acne, that prevent rather than treat the disease, it is necessary to identify the factor(s) that determine acne-proneness or trigger the earliest, potentially reversible, inflammatory changes.

This small study has shown that acne patients may have a central defect in IL-10 production by peripheral blood mononuclear cells that makes them incapable of mounting a sufficiently vigorous anti-inflammatory response to minor immunologic stimuli within pilosebaceous follicles where acne lesions develop. Reduced production of IL-10 was shown to be associated with a paucity of CD14+ monocytes/immature macrophages in acne patients compared with age-matched healthy controls. The immunogen used to stimulate monocytes was whole live cells of Propionibacterium acnes, the bacterium implicated in inflammatory acne.

IL-10 is the predominant cytokine that dampens down the inflammatory response and over-production in late lesions has been demonstrated. Once inflammation becomes established, up-regulation of IL-10 production may help to resolve existing lesions and cellular sources other than monocytes may contribute to local IL-10 synthesis at this late stage. It is the monocyte that is critical in the earliest stages. Monocytes are vital components of immune surveillance within the skin. They are the first troops on the scene when an inflammatory stimulus is detected. If their response in inadequate, the sub-clinical event is not contained and visible inflammation will ensue.

If others confirm this deficit in IL-10 production in acne patients, then we shall be a step closer to identifying the earliest pathogenic changes in acne. However, we still have to address the question as to whether P. acnes is universally present in sub-clinically inflamed follicles or whether the pro-inflammatory stimulus is non-microbial. A key role for IL-1 alpha in acne has long been suspected since Guy and Kealey (Dermatology 1998; 196:32-7) demonstrated that this cytokine alone can trigger comedogenesis. It is present in large amounts in comedones and its release by keratinocytes can be triggered by an injury response, for example, the onset of sebum flow though an immature duct. Whether the defective monocytes are attempting to respond directly to P. acnes or indirectly to IL-1 alpha, the consequences in terms of unchecked inflammation will be similar.

Further reading:

Caillon F, O'Connell M, Eady EA, Jenkins GR, Cove JH, Layton AM, Mountford AP. (2009) Interleukin-10 secretion from CD14+ peripheral blood mononuclear cells is downregulated in patients with acne vulgaris. Br J Dermatol. 2009 Jul 20. [Epub ahead of print]

European dermatologists are told to steer clear of topical antibiotics

2009-10-16T08:25:00.000-07:00

By E Anne Eady and Sarah Gregory

Last week saw the 18th congress of the European Association of Dermatology and Venereology. Held in Berlin from the 7-11th of October, the meeting brought together about 10,000 dermatologists and scientists from all over the world and covered the most recent developments in clinical and experimental dermatology and venereology.

One clear message that came through during the main acne symposium was that expert opinion no longer endorses the use of topical antibiotics for the management of mild to moderate acne unless co-prescribed with benzoyl peroxide to minimise the risk of resistance. Retinoids are very much the in favour acne treatment at the moment but retinoids alone have no effect on P. acnes so that their efficacy versus inflamed lesions is sub-optimal.

A similar consensus was shown during the ‘Topical antimicrobial therapies’ session, chaired by Richard Gallo. The use of topical antibiotics to treat superficial skin and wound infections is being actively discouraged within the EU. Dermatologists were told that the benefits simply did not outweigh the risks with much concern over the promotion of drug resistance. Certainly the pendulum has swung again – away from topical antibiotics and towards topical antiseptics.

Whilst this is undoubtedly good news to those who seek to control the spread of antibiotic resistance, the implications for individual patients are not so great. For acne, benzoyl peroxide is a great alternative or adjunct to antibiotics but it will never be a patients’ treatment of choice because of its powerful bleaching action that ruins clothes and household linens. We urgently need alternative antimicrobials that are as efficacious as benzoyl peroxide but without the downsides. The ideal treatment for acne would specifically target P. acnes whilst leaving the rest of the resident flora intact. Of note is the report from the German healthcare giant Henkel who showed that several plant extracts inhibit P. acnes but have no effect on beneficial species like coagulase-negative staphylococci in vitro or in vivo (Bockmuhl et al. Int J Cosmet Sci 2007; 29: 63-6).

Re-balancing the microflora of skin would be much more difficult in the treatment of wounds where several pathogens are often present and, by definition, the integrity of the skin has been breached. Local application of the non-skin bacterium Lactobacillus plantarum has been used in infected burn wounds with success rates comparable to silver sulphadiazine (Peral et al. Int J Wound 2009; 6:73-81). The latter, like benzoyl peroxide, has its downsides. Whilst silver’s ability to kill a broad spectrum of bacteria is perfect for tackling the many different organisms that can infect a wound, there is concern about delayed healing. Local application of honey is well known to have beneficial effects on wounds especially that from Manuka trees which contain more antibacterial phytochemicals. However, the mode of action of honey is complex and it is unlikely to have differential effects on good versus bad bacteria.

With experts recommending we cut back on antibiotics, it is wise to question just how suitable the alternatives are. With limited choice of non-antibiotics and patients demanding less use of ‘chemicals’, can we be sure that dermatologists will heed expert recommendations and ensure they are adhered to in clinical practice? The need for novel antimicrobials with improved risk-benefit profiles and more consumer appeal could not be more acute. Now is the time for research and product development to catch up with public opinion and medical need.

Antimicrobial activity of 2-tert-butylhydroquinone (TBHQ) and bismuth or copper, new synergistic combinations for the treatment of acne

2009-08-07T02:09:00.000-07:00

By Daniel Fitzgerald, Priscila Gottardello, Scott Seville, E Anne Eady, and Jon H Cove

Acne affects a majority of the adolescent and young adult population. It is a multifactorial disorder associated with Propionibacterium acnes infection of functionally blocked pilosebaceous follicles. Commonly treated with topical antibiotics, concerns regarding increasing resistance have led to the need for alternative anti-infectives. 2-tert-butylhydroquinone (TBHQ) is a lipophilic sterically hindered hydroquinone often used as an antioxidant in foodstuffs rich in fats or oils. The antimicrobial properties of TBHQ against food-related bacteria are well known but the compound’s pronounced activity against propionibacteria is a recent discovery [WO-2006/100496]. Under appropriate conditions, TBHQ can be oxidised to 2-tert-butylbenzoquinone (TBBQ) with which it exists in a redox couple. The oxidation reaction proceeds in two stages via a semiquinone intermediate resulting in free radical generation. At neutral to acidic pHs, the reaction occurs slowly but can be catalysed by transition metal ions such as copper. In order to determine whether this mechanism could boost the antimicrobial activity of TBHQ, we compared the potency of TBHQ in the presence and absence of two metal salts. Using a modified disk diffusion assay (DDA), TBHQ in combination with either copper sulphate (CuSO4), or bismuth subsalicylate (BiSS), a non-transition metal salt, markedly increased the mean zone of inhibition (ZoI) above that of the most active compound alone against Propionibacterium acnes NCTC737. Mean ZoIs from triplicate assays increased by 11.68 mm (50.3% area increase) in combination with CuSO4 and by 10.83 mm (129.6% area increase) with BiSS. Similar levels of potentiation in modified DDAs were observed using different copper and bismuth salts. The potentiation of TBHQ with either CuSO4 or BiSS versus P. acnes was confirmed against a panel of antibiotic susceptible and resistant propionibacterial strains. Checker-board fractional inhibitory concentration (FIC) assays showed the interaction of TBHQ with CuSO4 or BiSS against P. acnes to be synergistic with lowest FIC indices of 0.5 and 0.31 respectively (synergy = FICI ≤0.5). Synergistic combinations of TBHQ with copper or bismuth offer a novel antimicrobial treatment for acne against which bacterial resistance would be unlikely to develop.

Syntopix is currnetly presenting it latest research at the American Academy of Dermatology's summer meeting in Boston (29th July - 2nd August). The above abstract on TBHQ is poster number and can be viewed in full by clicking here. 101

TBHQ represents a new class of antibacterial for topical applications in dermatology

2009-08-03T02:26:00.001-07:00

By Daniel Fitzgerald, Andleeb Qureshi, and Jon H Cove

Issues concerning the overuse of topical antibiotics and the emergence of resistance have lead to a need for novel antimicrobials for dermatological applications. Repositioning known chemical entities with a history of use in man offers a more effective development route in terms of time, money and risk. 2-tert-butylhydroquinone (TBHQ) is a sterically hindered lipophilic hydroquinone used extensively as an antioxidant, especially to inhibit peroxidation of unsaturated fats. The compound is a permitted direct food additive and a permitted cosmetic ingredient in both the US and EU. It therefore represents an excellent repositioning candidate. Experiments were carried out in order to evaluate its suitability as a topical anti-staphylococcal and anti-propionibacterial agent. In vitro tests showed that TBHQ was active against a panel of 10 antibiotic susceptible and resistant coagulase-negative staphylococci (MICs 0.98-7.8 mg/L) and 16 Staphylococcus aureus isolates including MRSA, VISA and GISA strains (MICs 1.95 – 7.8 mg/L). TBHQ was also active against strains of Propionibacterium acnes and Propionibacterium granulosum resistant to erythromycin, clindamycin and related antibiotics via target site mutation or methylation of 23S rRNA and/or to tetracyclines via target site mutation of 16S rRNA. MICs of TBHQ for 21 propionibacterial antibiotic susceptible and resistant isolates ranged from 1.95 to 15.6 mg/L; one isolate of P. granulosum showed reduced susceptibility (MIC 62.5 mg/L). Time to kill studies using suspensions of P. acnes NCTC737 in aqueous buffer showed that TBHQ at 31.25 mg/L is rapidly bactericidal. Current knowledge of its mode of action suggests that TBHQ affects multiple cellular processes including both direct effects due to TBHQ itself and indirect effects attributed to free radicals generated via oxidation to 2-tert-butylbenzoquinone. It is therefore unlikely that resistance would emerge during clinical use. TBHQ has physicochemical characteristics ideal for topical delivery and retains antimicrobial efficacy in the presence of salt and skin lipids. In view of its safety profile, physicochemical properties and antimicrobial potency, TBHQ represents a novel drug candidate for the local treatment of acne and/or the prevention of staphylococcal skin infections.

Syntopix is currnetly presenting it latest research at the American Academy of Dermatology's summer meeting in Boston (29th July - 2nd August). The above abstract on TBHQ is poster number 402 and can be viewed in full by clicking here.

Heme Oxygenase -1 - An overlooked potential target in inflammatory skin disease?

2009-07-30T06:22:00.000-07:00

By Wayne Burrill, E Anne Eady and Jon H Cove

Studies of heme oxygenase in keratinocytes are few despite it being an accessible target for pharmacological manipulation. We have used an immortalised human keratinocyte line to demonstrate the possibility of synergistically up-regulating keratinocyte heme oxygenase-1 (HO-1) as a novel means of treating inflammatory dermatoses such as acne, atopic dermatitis and psoriasis. HO-1 is the inducible rate-controlling enzyme that catalyses the conversion of heme to ferrous iron, bilirubin and carbon monoxide. HO-1 possesses anti-inflammatory, cytoprotective and immunosuppressive effects and hence limits tissue damage caused by reactive oxygen species. The transcriptional activator, Nfr2, is intimately involved in the regulation of HO-1 gene expression. Cytosolic Nfr2 is phosphorylated and translocated into the nucleus in response to activation of mitogen-activated protein kinases (MAPKs). Most known inducers of HO-1 including antioxidants such as curcumin and carnosol target protein phosphorylation cascades. Cobalt protoporphyrin IX (COPP) and metal salts on the other hand appear, at least in part, to target Bach-1 by promoting its nuclear export. Bach-1 is a transcriptional repressor, heterodimers of which normally suppresses transcription of the HO-1 gene by binding to the stress response elements within the promoter region. Using ELISA to detect HO-1 levels in lysates from HEK001 cells grown for 72 h without inducer followed by 24 h with different concentrations of inducer, we found that CoPP at 0.78 to 3.12 μM induced a >200 fold increase in HO-1 protein compared to baseline levels. Using the photosensitiser and heme precursor, aminolevulinic acid (ALA), the maximum increase in HO-1 production was 21 fold at 1 mM. When 100 μM ALA was combined with 100 μM cobalt chloride, the maximal increase in HO-1 production was 260 fold compared to baseline, 320 fold compared to 100 μM cobalt chloride alone and 32 fold compared to 100 μM ALA alone. When cobalt chloride was used alone the maximum induction of HO-1 protein production was 15 fold at 1mM. We hypothesise that ALA and cobalt chloride affect different aspects of the HO-1 regulatory pathway and this results in a synergistic inducing effect as previously observed in hepatoma cells (Mitani et al. Biochem J 1993; 290: 819-25). Identifying other combinations of compounds that synergistically modulate aspects of HO-1 regulation represents a novel approach to the development of topical anti-inflammatories.

Syntopix is currnetly presenting it latest research at the American Academy of Dermatology's summer meeting in Boston (29th July - 2nd August). The above abstract on heme oxygenase is poster number 400 and can be viewed in full by clicking here.

The search for P. acnes inhibitors

2009-07-03T02:02:00.000-07:00

By Dr Nicholas Reed

The search for novel antimicrobials
The search for novel agents that are active against Propionibacterium acnes in vivo is not straight forward. One of the basic measures of antimicrobial activity in the laboratory is the minimum inhibitory concentration (MIC). The MIC can be defined as the lowest concentration of a compound that prevents visible growth of the organism. Typically MICs are carried out in complex aqueous culture media, either by agar dilution on solid medium or by broth microdilution. These complex media typically contain protein hydrolysates, components of which can interfere with the antimicrobial activity of many compounds. In skin, P. acnes is typically not found in peptide/protein rich environments. Its primary cutaneous habitat is within the ducts of pilosebaceous follicles that are most prevalent on the face and upper trunk. These follicles possess a small vellus hair and a disproportionally large sebaceous gland. Such follicles secrete sebum, an oily substance that consists predominantly of squalene, wax esters and triglycerides and has little similarity to microbiological culture media. Native sebum does not contain water.

It is thought that the differences between sebum and aqueous culture media account, in part, for the lack of correlation between the MIC of many antimicrobial compounds and their clinical efficacy. This lack of correlation between MICs and in vivo activity versus P. acnes is exemplified by benzoyl peroxide (BPO). BPO is the most widely used over the counter acne treatment, with sales in excess of $1 billion per annum (Tanghetti and Popp, 2009). Despite its known and well established efficacy in the treatment of acne, the MIC of BPO for P. acnes ranges from 100 to 800 µg/ml (Decker et al, 1989) in one study and from 64 to 128 in another (Eady et al, 1994). These values are much higher than the threshold for efficacy recommended in many antimicrobial screening programmes (Chopra and O’Neill, 2004) and exceed by over a 100 fold the MICs of anti-acne antibiotics like erythromycin, clindamycin and the tetracyclines for P. acnes. MICs underestimate the potency of BPO for several reasons, including the inherent instability of the compound in many biocompatible solvents and its inactivation by components of complex microbial culture media.

Clearly, so as not to miss out on potentially useful treatments, a method is needed that tests the activity of compounds against P. acnes, in an environment similar to that found within the follicle.

Artificial sebum
A number of artificial sebum mixtures have been developed. Many of the mixtures used have very different compositions, some being made up of just triglycerides and fatty acids, others being mixtures of squalene, wax esters, triglycerides, fatty acids, cholesteryl esters and cholesterol. The most abundant fatty acids in sebaceous lipids contain 14, 16 or 18 carbons (Nicolaides, 1974)); over 200 different ones are present, some unique to human sebum. Many are unsaturated at unusual positions, have odd carbon numbers and/or are methylated, making imitation of real sebum impracticable. A widely used model contains triglycerides and wax esters base on palmitic and palmitoleic acid (Motwani et al 2004). Palmitic acid (C16:0) is the most abundant fatty acid in sebum, closely followed by sapienic acid (C16:1D6). Other recent sebum models include those of Wertz (2009) and Lu et al. (2009). That of Wertz is unusual in that 6% of water can be stably incorporated. Free fatty acids are not present in native sebum but are released by the action of microbial (mainly propionibacterial) lipases on triglycerides. Hence their relative concentrations vary extensively from person to person and follicle to follicle.

The physical properties of artificial sebum (melting point, viscosity, etc) will depend in large part on the types of fatty acid in the triglyceride and wax ester fractions as well as on their relative proportions (Motwani et al, 2002). Different components of sebum melt at different temperatures. A sebum model useful for examining the effects of antimicrobials on P. acnes must contain water and must be fully liquid at 37oC.

Identifying the ideal recipe
Given the choice of sebum recipes available, what would constitute the ideal sebum mixture for use in the screening of compounds for inhibition of P. acnes? Ideally the sebum formulation would be:

1) Based on samples taken from a wide range of people.
It has been demonstrated that sebum composition varies from one person to another, for example the ratio of wax esters to cholesterol plus cholesterol esters has been shown to increase in boys from age 9 to 15 (Stewart, Steele and Downing, 1989). Similarly the ratio of straight chain fatty acids to branched chain fatty acids has been shown to increase to the age of about 20 and then decrease to the age of 50 (Yamamoto et al, 1987). Diet also appears to play an important role in sebum composition, for example it has been observed that the ratio of saturated to monounsaturated fatty acids in the skin surface triglycerides increases in people put on a low glycemic load diet (Smith et al, 2008).

2) Based on samples taken from people with acne.
More differences in sebum appear to be age related than acne related and there is as yet, no identified ‘fingerprint’ for acnegenic sebum. However, sebum from people with acne contains less linoleic acid and more sapienic acid than sebum from people without acne (Downing et al 1986). Powell and Beveridge (1970) also reported significant differences in the triglyceride and wax ester content of sebum taken from men with high levels of acne compared to men without, or with minimal, acne.

3) Affordable and contain readily available constituents.
For routine screening an important consideration is cost and availability. Many artificial sebum mixtures use expensive reagents, for example Lu et al. (2009) and Nordstrom et al (1986) use 5 to 16.67% palmitoleic acid in their artificial sebum mixtures. The current Sigma list price of palmitoleic acid is £99.70 for 1g. Many of the abundant but unusual fatty acids in sebaceous triglycerides and wax esters are not commercially available.

4) Contain water.
Water is essential for bacterial viability and growth. However, it is not known whether the sebum/water mix that must exist within colonised follicles exists as a stable or unstable emulsion or whether there are simply pockets of water immersed within a predominantly lipid milieu. The origins of water within the upper reaches of pilosebaceous follicles have not been identified. One possibility is sweat but whether this can penetrate sufficiently to permit bacterial growth in the deeper infundibulum is not known.

5) Have similar physiochemical properties to human sebum.
Lu et al. (2009) were able to demonstrate a good level of similarity between their artificial sebum, and sebum taken from human volunteers, through use of NMR, differential scanning calorimetry, partition coefficient analysis and diffusion studies.

6) Not contain antimicrobially active components in inhibitory amounts.
Several fatty acids present in human sebum have been shown to possess antibacterial activity under laboratory conditions. These include lauric acid (C12:0), linoleic (C18:2D9,12) and linolenic (C18:3D9,12,15) acids, palmitoleic acid (C16:1D9) and sapienic acid (C16:1D6). Of these, only lauric acid and its corresponding monoglyceride, monolaurin, appear to inhibit P. acnes in vitro [data on file].

7) Be shown to demonstrate a close correlation between in vitro and in vivo studies. Ultimately this is the key factor. Agents with known anti-P. acnes activity in vivo, such as BPO and tetracyclines, are good model compounds to use to establish the usefulness and predictive value of sebum model mixtures. Without more research into the physicochemical properties of real sebum, all models are likely to have very low predictive values.

References

Decker LC, Deuel DM, Sedlock DM. (1989) Role of lipids in augmenting the antibacterial activity of benzoyl peroxide against Propionibacterium acnes. Antimicrob Agents Chemother; 33: 326-30.

Downing DT, Stewart ME, Wertz PW, Strauss JS. Essential fatty acids and acne. J Am Acad Dermatol 1986: 14: 221-5.

Eady EA, Farmery MR, Ross JI, Cove JH and Cunliffe WJ. Effects of benzoyl peroxide and erythromycin alone and in combination against antibiotic-sensitive and –resistant bacteria from acne patients. Br J Dermatol 1994; 131: 331-6.

Lu GW, Valiveti S, Spence J, Zhuang C, Robosky L, Wade K, Love A, Hu LY, Pole D, Mollan M. Comparison of artificial sebum with human and hamster sebum samples. Int J Pharm 2009; 367: 37-43.

Motwani MR, Rhein LD, Zatz JL. Influence of vehicles on the phase transitions of model sebum. J Cosmet Sci 2002; 53: 35–42.

Motwani MR, Rhein LD, Zatz JL. Deposition of salicylic acid into hamster sebaceous glands. J Cosmet Sci 2004; 55: 519-31.

Nicolaides N. Skin lipids: their biochemical uniqueness. Science 1974; 186: 19-26.

Nordstrom KM, Labows JN, McGinley KJ, Leyden JJ. Characterization of wax esters, triglycerides, and free fatty acids of follicular casts. J Invest Dermatol 1986; 86: 700-5.

O'Neill AJ, Chopra I. Preclinical evaluation of novel antibacterial agents by microbiological and molecular techniques. Expert Opin Investig Drugs 2004; 13: 1045-63.

Powell EW, Beveridge GW. Sebum excretion and sebum composition in adolescent men with and without acne vulgaris. Br J Dermatol 1970; 82: 243-9.

Smith RN, Braue A, Varigos GA, Mann NJ. The effect of a low glycemic load diet on acne vulgaris and the fatty acid composition of skin surface triglycerides. J Dermatol Sci 2008; 50: 41-52.

Stewart ME, Steele WA, Downing DT. Changes in the relative amounts of endogenous and exogenous fatty acids in sebaceous lipids during early adolescence. J Invest Dermatol 1989; 92: 371-8.

Tanghetti EA, Popp KF. A current review of topical benzoyl peroxide: new perspectives on formulation and utilization. Dermatol Clin 2009; 27: 17-24.

Wertz PW. Human synthetic sebum formulation and stability under conditions of use and storage. Int J Cosmet Sci 2009; 31: 21-5.

Yamamoto A, Serizawa S, Ito M, Sato Y. Effect of aging on sebaceous gland activity and on the fatty acid composition of wax esters. J Invest Dermatol 1987; 89: 507-12.

Misleading cosmetic claims: have we reached a turning point?

2009-06-01T02:08:00.000-07:00

Increasingly, cosmetic companies are coming under scrutiny for misleading the public with efficacy claims that are ambiguous or have insufficiently rigorous scientific proof. It is the opinion of many that tighter legislation, regulations and guidelines need to be enforced so that all companies have set rules to follow when designing studies to validate claims. This would not only save the consumer a small fortune on products which don’t do what they “think” they do but it would also increase consumer confidence that the money they do spend will be on products that deliver against expectations.

There is already self-regulation such as the Committee of Advertising Practice (CAP) in the UK which produces codes of practice aimed to protect consumers and is administered by the Advertising Standards Authority. The regulators can and do look for evidence of compliance with codes of advertising practice but in fact very few breach them. In the most recent CAP survey of 445 cosmetic ads, only 7% were found to be non-compliant. However, the survey did reveal continued issues with ambitious performance claims that could not be properly substantiated. Despite this, there are very few instances of claims having to be withdrawn. Why then is there a general public perception that many cosmetics do not live up to the claims they make?

The concept of cosmetics is that application of substances to body surfaces will enhance their appearance and hence our attractiveness. Most of us buy cosmetic products in the hope that they will make us feel better about ourselves. Perhaps this is why we are so willing to believe cosmetic claims only to reject the product later when we realise that it does not fulfil our expectations. If the consumer finds certain types of product over-promise but under-deliver, then claims validation needs to reflect what the consumer expects to have been demonstrated. Whilst most of us are happy to purchase a cosmetic which states ‘this product has not been tested on animals’, how would we feel about one that said ‘the effectiveness of this product has not been tested in humans’? Scientifically, claims will always carry more weight when they have been validated by a combination of both laboratory tests and human use studies. Both have their place when determining the balance between the scientific rationale for justifying claims and the cost and expense of achieving such claims.

In recent weeks Boots has published human use data regarding one of its anti-ageing products, and this possibly represents a better way forward for claims justification of dermatological cosmetic products. Click here for a link to the original peer reviewed research article published in a highly respected dermatology journal. By showing that the product reduces facial wrinkles more effectively than the vehicle in a properly blinded, randomised, controlled trial and by concomitantly showing significant changes in a relevant biological marker (fibrillin), the company has changed the rules of the game. Sales are predicted to increase based on the assumption that consumers will now believe the claims are matched by performance and it is certain that the brand’s performance will be watched closely by the competition. Investment in sound scientific testing can reap significant financial rewards. Products in development must undergo rigorous in vitro AND in vivo tests to ensure the claims used to entice consumers really do lead to visible improvement in their skin.

Here in the UK, the CTPA has recently issues a comprehensive guide to advertising claims aimed at manufacturers. Wouldn’t it be good if they decided to publish a related guide for consumers? There is no doubt that the bar for testing of cosmetics has been permanently raised.

Rapid clinical evaluation of topical anti-acne formulations: more speed, less haste?

2009-05-12T03:41:00.000-07:00

Clinical trials to evaluate the efficacy of novel acne preparations traditionally are conducted over many weeks to monitor changes in the total number of different types of lesion. Until recently, there has been no attempt to discriminate between effects on pre-existing lesions versus the prevention of new lesion formation. There are also several well established grading scales such as the Burke & Cunliffe(1) or the Allen & Smith(2) which have been shown to be accurate and reproducible. It is however recognised that these approaches are time consuming, labour intensive and as a result costly to complete. Due to the complexity of acne presentation, it is recommended by the FDA that severity scoring includes lesion counting, where both inflamed and non-inflamed lesion are counted, as well as a more holistic grading by a physician in which the entire presentation is categorised by comparing against an established scale of severity(3).

These involved and lengthy methods for clinical evaluation are necessary when trialling a new medicinal. Regulatory approval requires substantiated and scientifically validated data that the active is clinically effective and safe. However, when developing a novel cosmetic product a quicker and cheaper method for demonstrating a positive impact on spots is more desirable.

Acne has classically been regarded as a slowly responding disease with treatments typically taking months to achieve maximum clinical benefit. However, pressure from marketing departments in an increasingly competitive cosmetic market for acne products is driving research on outcomes that demonstrate benefits in acneic skin within ever shorter timelines. There have been numerous attempts at developing alternative methods and we recently came across an article that claims a rapid method for the clinical assessment of anti-acne formulations(4). Authored by employees of Estee Lauder companies, the publication describes how they tracked the progress of individual lesions, grading the severity of the spots over a period of 5 days using a Scopeman surface microscope and digital image analysis. To view the abstract please click here. Johnson and Johnson are also exploring new ways of quantifying the extent of erythema associated with individual lesions, assessing such techniques as diffuse reflectance spectroscopy, fluorescence spectroscopy and spectral imaging(4). Whilst such methods are to be welcomed, they are as yet limited by a lack of basic knowledge on the natural history of acne lesions. There is very little information in the public domain about how long different types of spot persist or how they evolve in the absence of any therapeutic intervention. This groundwork needs doing before seeking evidence of short term therapeutic benefits on individual lesions. Current wisdom suggests that most but by no means all inflammatory lesions arise from visible comedones(6, 7) whilst others arise from microcomedones(8) or de novo within areas of apparently clear skin(7). Whilst many inflamed spots resolve within two weeks(7), others persist for months as inflammatory macules which can ultimately heal or flare. How may lesions need to be monitored within an individual to obtain an accurate picture of that individual’s response to treatment? When is a lesion not a lesion? At what point do we say an inflammatory lesion has resolved? When it is no longer palpable or when it is no longer erythematous? What about comedones? Might image analysis help to assess treatment effects on these more refractory lesions? In some individuals they are so crowded together, especially on the forehead, that following individual ones could be virtually impossible.

Even with digital image analysis, can we be sure that we align individual follicles? Given that there are between 290 and 450 follicles per cm2 skin9, and a typical papule can be 2-3 mm across, then underneath each ‘lesion’ there will be between 9 and 36 follicular openings. Where lesions are crowded together as they often are in moderate acne (Figure 1), how can we be sure that what started out as a lesion in one follicle doesn’t alter over time to a lesion in a quite different follicle that happens to lie within the area of inflammation of the original one? If we choose to monitor only isolated spots to make the analysis easier and clearer, is the response of these spots representative of those in more involved areas of skin?

Whilst following individual lesions may be a valuable tool for screening prototype formulations at an early stage in product development or producing attractive marketing material can it really be considered a viable alternative to monitoring the number and type of lesions within a defined area over a period of 8-12 weeks? It is clear that consumers want fast results from the products they use but a lasting effect is also desirable. Surely then it is important to also look at how the product or treatment impacts the formation of new spots.

It will be a considerable advantage to have access to simple, reproducible methods for capturing short –term effects of acne products both cosmetic and medicinal. These should not be considered a replacement for outcome measures that estimate longer term benefits, rather they give us a way of looking for the first time at true therapeutic effects as opposed to preventative ones.

1. Allen, B.S.; Smith, J.G., Jr., Various parameters for grading acne vulgaris. Arch. Dermatol. 1982, 118: 23 – 25

2. Burke, B.M., Cunliffe, W.J., The assessment of acne vulgaris: the Leeds technique. Br J Dermatol. 1984;111: 83-92.

3. Tan J. C., Current measures for the evaluation of acne severity: methods of grading acne severity. Expert Rev Dermatol. 2008;3(5):595-603.

4. Muizzuddin, N., Maes, D.H., Mammone, T., A rapid method to clinically assess the effect of an anti-acne formulation. J Cosmet Sci. 2009 Jan-Feb;60(1):25-9.

5. Fong, J., Stamatas, G., Estanislao, R,. New methods for evaluating inflammatory acne dynamics. J Am Acad Dermatol 2004; 50(3) suppl 1: P21.

6. Orentreich, N., & Durr N. P,. The natural evolution of comedones into inflammatory papules and pustules. J Invest Dermatol (1974) 62: 316–320.

7. Do, T., T., Zarkhin, S., Orringer, J., S., Nemeth, S., Hamilton, T., Sachs, D., Voorhees, J., J., Kang, S,. Computer-assisted alignment and tracking of acne lesions indicate that most inflammatory lesions arise from comedones and de novo. J Am Acad Dermatol 2008; 58: 603-8.

8. Cunliffe, W., J., Holland, D., B., Jeremy, A,. Comedone formation: etiology, clinical presentation and treatment. Clin Dermatol 2004; 22: 367-74.

9. Otberg N, Richter H, Schaefer H, Blume-Peytavi U, Sterry W, Lademann J. Variations in hair follicle size and distribution in different body sites. J Invest Dermatol 2004; 122: 14-19.
http://www.nature.com/jid/journal/v122/n1/full/5602116a.html

Natural Preservatives

2009-04-16T02:36:00.000-07:00

An article that we recently came across illustrates well the trend towards the use of natural ingredients as preservatives in cosmetics and toiletries. It can be seen that in many cases the chemistry of these ingredients is well understood.

However public perception of what constitutes the difference between a ‘chemical’ and a ‘natural’ product may be less clear (see the Syntopix Chemical Questionaire). It is interesting to see the diversity of compounds involved and surprising to find that several widely used chemicals in fact have their origins in nature. To read the article ‘An update on natural preservatives’ by Antony C Dwerck please click here.

The article was originally published in the Personal Care Magazine 6, 4. pages 11-15 (2005).

The author’s website contains a wealth of information on using naturals in cosmetic formulations and has a very useful list of publications which can be accessed by clicking here.

Artificial sebum: finding the right recipe

2009-04-09T02:29:00.000-07:00

It is widely believed that targeted transfollicular delivery of topically applied drugs could be a way of increasing the local efficacy without increased risk of systemic exposure. The hair and sebaceous follicles are however lipid rich environments and it is important that the therapeutic agent is both stable and active in sebum. Characterisation of potential topical agents have been hampered by the fact that collection of human sebum is difficult and that there have been no standardised formulations of synthetic sebum. Many of the synthetic sebum formulations that have been used do not closely resemble actual sebum.

A recent paper by Lu et al describes a synthetic sebum which has been shown to have many characteristics (NMR spectrum, diffusion and partition properties) that are the same as human sebum. Could this represent an artificial sebum that could be used as a real alternative to human sebum during product development?

To read the abstract click here.

P. acnes biofilms – where is the evidence that they are important in skin colonisation or acne?

2009-04-02T07:51:00.000-07:00

By Dr Anne Eady

Biofilms are fashionable; research on them is newsworthy. Biofilms are probably best known as the first step in the formation of dental plaque which, if untreated, can lead to decay or gum disease depending where it forms on the tooth surface. Biofilms have also been linked to acne as a means to explain why antimicrobial treatments don’t always work. But where is the evidence that P. acnes grows as a biofilm in its natural habitat of the skin?

First of all, let’s explain what a biofilm is and why biofilm formation might be an important determinant of treatment outcomes. When bacteria grow in a liquid, they typically do so as single cells or small clumps. An antibacterial compound in the liquid is able to access all of the cells and exert its effect. This is rather like bacteria growing in the bloodstream and is called planktonic growth. When bacterial cells grow on a surface, they must adhere to that surface or risk falling or being washed off. Different kinds of bacteria produce different kinds of molecule on their cell surface to help them stick to receptors on human cells (a bit like a lock and key) and to inanimate surfaces via van der Waal’s forces. Sometimes, the bacteria stick only to surfaces that have been coated by a body fluid such as saliva or serum. Sometimes the adhering cells secrete a surface layer typically made of a polymer of a sugar, protein or even a lipid to help them stick better. This loosely adherent material constitutes a biofilm. Eventually the bacteria become embedded in this sticky layer where they are protected from adverse environmental factors. When this happens, antibacterial substances cannot penetrate the biofilm and so the bacteria just keep on growing. Cells living in a biofilm are said to be sessile. Their behaviour as well as their susceptibility to antibacterial agents can and does change usually for the worse. They may become more or less virulent. The concentrations of substances they secrete can reach very high local levels and cause damage to host tissue.

A biofilm may contain a single species of bacterium or, more commonly a mixture of several species. Some bacteria are called early colonisers because they can stick directly to the surface in question. Other bacteria stick to the ones that have already stuck but cannot stick directly to the surface if the early colonisers are absent. This explains why dental plaque is a complex community of many different species. We know plaque exists because we can see it, we can collect it and we can analyse it. There is no doubt that plaque begins as a simple biofilm because we can watch it develop on the tooth surface or in a model of the mouth.

But what about the bacteria that live on the skin? Are biofilms important here too? A simple search of PubMed, the database of medical and scientific literature, generates 223 hits for biofilm and skin out of a total of almost 11,000 references to biofilms, a mere 2%. Of these, very few refer to biofilms made by skin bacteria in their natural environment. Most concern the formation of biofilms on the surfaces of catheters or prostheses by coagulase-negative staphylococci, ubiquitous residents of healthy human skin.

Four different research groups have addressed the issue of P. acnes biofilms. One group (Sheila Patrick, Gordon Ramage and Michael Tunney) found that P. acnes forms biofilms on orthopaedic implants and that such biofilms are more resistant to several antibiotics than planktonic grown cells. A prerequisite for sustained growth on an inanimate surface like polymethylmethacrylate bone cement is the capacity to form a biofilm, van der Waals forces being too weak on their own and no specific receptors being present. Given the known role of P. acnes as a coloniser of implanted devices, these results are perhaps not so surprising. Roger Bayston and co-workers confirmed that P. acnes can form biofilms on several different types of inanimate surface with or without pre-treatment with plasma; the biofilms required longer than usual courses of antibiotics to effect complete eradication. Most importantly they confirmed the existence of a P. acnes biofilm formed in vivo within a ventriculoperitoneal shunt. A third group (Tom Coenye and colleagues) grew P. acnes biofilms on polystyrene and showed that they had a different susceptibility profile to antimicrobials used to treat acne than cells grown in liquid culture. However, this group used antimicrobials at concentrations present in topical formulations (2% salicylic acid, 2.5% benzoyl peroxide), not the much lower concentrations found at the target site. The final group (Burkhardt and Burkhardt) theorised about the possible role of P. acnes biofilms in acne pathogenesis. They noted that the P. acnes genome sequence contains at least three gene clusters involved in polysaccharide capsule biosynthesis. They interpreted this as confirmation of the potential of this organism to form biofilms under appropriate growth conditions and proposed two main ways in which biofilms might be important in acne: (1) as a physical barrier to prevent treatments working, (2) as a driver of inflammation. They suggest that biofilms may explain why antibiotics take so long to work and why benzoyl peroxide is so effective, their idea being that small free radicals can penetrate the biofilm whereas antibiotics and intact benzoyl peroxide cannot.

Fascinating though all of this is, as yet there is no proof that P. acnes grows as a biofilm in its natural habitat. In fact there is no evidence that any resident skin bacteria grow as biofilms either on the surface of healthy skin or within sebum-filled follicular ducts. Of course, absence of evidence is not the same as saying the existence of biofilms must therefore be false, but simply that evidence of biofilms in human skin has not been sought. Almost certainly, biofilms are not implicated in growth on the surface of corneocytes, upon which clear microscopic evidence of exposed microcolonies of P. acnes can be seen in washings taken from the skin. Moreover, it has recently been shown that carriage of the gene for a polysaccharide adhesin (icaADBC) in Staphylococcus epidermidis negatively affects ability to colonise intact skin (Rogers KL et al. Appl Environ Microbiol 2008; 74: 6155-7). Once the skin has been wounded and a serous exudate is present, biofilm formation becomes an important pathogenic determinant. It is plausible that the resident flora of skin comprises those genera and species that have the ability to colonise healthy skin via the possession of specific and possibly multiple adhesins. An example of such a specific interaction is staphylococcal clumping factor B with keratin 10, a surface expressed epithelial keratin (Walsh EJ et al. J Biol Chem 2004; 279: 50691-99).

In summary we can conclude that:

1. P. acnes has the genetic capacity to form biofilms under appropriate growth conditions

2. P. acnes forms biofilms in vitro and in vivo on non-living surfaces

3. Biofilm grown P. acnes are physiologically different to planktonic grown cells and may show reduced or altered susceptibility to some antimicrobials

4. The existence of P. acnes biofilms in skin remains a theoretical possibility for which evidence so far is lacking.

Further reading
1. Bayston R, Nuradeen B, Ashraf W, Freeman BJ. Antibiotics for the eradication of Propionibacterium acnes biofilms in surgical infection. J Antimicrob Chemother 2007; 60(6): 1298-301.

2. Bayston R, Ashraf W, Barker-Davies R, Tucker E, Clement R, Clayton J, Freeman BJ, Nuradeen B. Biofilm formation by Propionibacterium acnes on biomaterials in vitro and in vivo: impact on diagnosis and treatment. J Biomed Mater Res A 2007; 81(3): 705-9.

3. Burkhart CG, Burkhart CN. Expanding the microcomedone theory and acne therapeutics: Propionibacterium acnes biofilm produces biological glue that holds corneocytes together to form plug. J Am Acad Dermatol 2007; 57(4): 722-4.

4. Burkhart CN, Burkhart CG. Microbiology's principle of biofilms as a major factor in the pathogenesis of acne vulgaris. Int J Dermatol 2003; 42(12): 925-7.

5. Burkhart CN, Burkhart CG. Genome sequence of Propionibacterium acnes reveals immunogenic and surface-associated genes confirming existence of the acne biofilm. Int J Dermatol 2006; 45(7): 872.

6. Coenye T, Honraet K, Rossel B, Nelis HJ. Biofilms in skin infections: Propionibacterium acnes and acne vulgaris. Infect Disord Drug Targets 2008; 8(3): 156-9.

7. Coenye T, Peeters E, Nelis HJ. Biofilm formation by Propionibacterium acnes is associated with increased resistance to antimicrobial agents and increased production of putative virulence factors. Res Microbiol 2007; 158(4): 386-92.

8. Coates T, Eady A, Cove J. Propionibacterial biofilms cannot explain antibiotic resistance but might contribute to some cases of antibiotic recalcitrant acne. Br J Dermatol 2003; 148(2): 366-7.

9. Ramage G, Tunney MM, Patrick S, Gorman SP, Nixon JR. Formation of Propionibacterium acnes biofilms on orthopaedic biomaterials and their susceptibility to antimicrobials. Biomaterials 2003; 24(19): 3221-7.

10. Tunney MM, Dunne N, Einarsson G, McDowell A, Kerr A, Patrick S. Biofilm formation by bacteria isolated from retrieved failed prosthetic hip implants in an in vitro model of hip arthroplasty antibiotic prophylaxis. J Orthop Res 2007; 25(1): 2-10.

Formulating the right effect

2009-03-31T02:37:00.000-07:00

A recent review article published in the International Journal of Cosmetic Science discusses the formation effects of topical emulsions on transdermal and dermal delivery.

The review illustrates just how difficult optimising skin delivery from emulsions can be. It makes interesting reading for all those developing topical formulations and discusses in detail the various influences that should be taken into consideration.

To read the abstract click here.

Topical Antimicrobials Network

2009-03-26T07:11:00.000-07:00

Join the Topical Antimicrobials Network on LinkedIn to connect with others interested in topical antimicrobial research and product development.

The ideal candidate

2009-02-26T01:38:00.000-08:00

A recent medscape question and answer article discussed the importance of limiting the use of oral antibiotics in the treatment of acne due to concerns over bacterial resistance and long term adverse events. The author suggested that combining oral antibiotics with effective topical regimens such as topical retinoids, benzoyl peroxide or topical antibiotics can limit the length of time that the patient needs oral antibiotics. This practice has benefits not only for the patient but also in terms of reduced treatment costs.

With the use of benzoyl peroxide producing undesirable side effects and the worldwide implementation of policies to restrict the use of antibiotics, it seems clear that novel antimicrobials targeting acne are needed. The question is what characteristics should such antimicrobials have?

Six attributes which should be given important consideration are listed below:

1) Specific anti-propionibacterial activity
The antimicrobial will have potent activity against the problem bacteria in acne, Propionibacterium acnes and Propionibacterium granulosum. Ideally, the compound will be uniquely active versus propionibacteria and will not adversely affect other components of the resident skin flora such as staphylococci. High potency must be retained in the presence of sebaceous lipids. Individually, each of these properties is hard to achieve, together they represent a significant hurdle.

2) No resistance concerns
There must be a low risk that resistance will develop against the compound itself and in turn that the compound has a low risk of promoting resistance to unrelated antibiotics. Resistance is more likely to develop to agents that have a single target within the bacterial cell. Some antibacterials, like benzoyl peroxide, have multiple targets within cells and also work very rapidly giving the cells little or no time to adapt. Such agents are to be preferred.

3) Easy to use
The antimicrobial should be capable of formulation into an easy to administer product which can be used both alone and in combination with other topical and systemic therapies depending on the duration, extent and severity of the acne

4) Available for oral and topical administration
Because acne varies from mild to severe and in distribution from highly localized to widespread, a new antimicrobial should be capable of oral and/or topical delivery. This gives physicians and patients the widest possible choice for dose optimization and avoidance of adverse effects.

5) Dedicated to acne
The ideal antimicrobial for acne would be used to treat acne and for no other purpose. It would be structurally unrelated to existing anti-acne antibiotics and have a different cellular target. Parallels amongst anti-staphylococcal agents are fusidic acid and mupirocin.

6) Capable of occupying more than one regulatory space
A new antibiotic for acne would be regulated as a prescription medicine in the first instance. A non-antibiotic could be regulated as a non-prescription medicine, a device or even as a cosmetic. This would put more control in the hands of the consumer and relieves pressure on overstretched healthcare budgets.

The first Syntopix blog post

2009-02-20T02:05:00.000-08:00

Welcome to the first Syntopix blog post. The aim is to provide opinion on current topical antimicrobial innovations or research and share our ideas on how technologies within this area are changing. We hope to discuss the latest scientific breakthroughs, the use of antimicrobials in cosmetic and medicinal products as well as our understanding of diseases processes. We hope you find the contents interesting!