The scientist credited with increasing demand for a skin cream that sold out in days after featuring in a television programme says that his results were achieved in contrived laboratory conditions — but that further scrutiny could lead to even greater success.

Chris Griffiths, Professor of Dermatology at the University of Manchester, told The Times that he was halfway through a clinical trial to examine whether the Boots No 7 Protect and Perfect Beauty Serum met the claims for it. This might lead to its becoming classed as a medicine for treating sun-damaged skin, he said.

The product was described as a wonder cream and sold out after a BBC Two Horizon programme in March said that it was as effective at combating sun damage – the most noticeable sign of ageing on the skin – as products that can only be prescribed by a doctor. Selling for as little as £16.75, the cream contains chemicals called pentapeptides. Boots has sold 5.6 million tubes since March, making it one of its top three bestselling products.

Asked whether his findings had been exaggerated, Professor Griffiths said that he had studied the effects of the cream on skin cells from the forearms of nine volunteers under a microscope and did not guarantee that it would work on faces. The new trial would attempt to discern whether the cream could achieve effects on the face that were visible to the naked eye, he said.

“Although a lot of work is done by reputable scientists using pentapeptides in the lab, and one can then extrapolate findings to suggest they will cause improvements in skin, there is a real lack of proper scrutiny on skin creams, so it was actually in quite contrived circumstances that I carried out the initial tests,” he said. “We were actually surprised to find that this one cream had any effect on reversing photo-aged skin. But that one observation was extrapolated to suggest that it worked in regular bodies.”

One of the main external factors causing skin ageing is sun exposure, leading to coarse skin and deep wrinkles, as distinct from fine wrinkles caused by the natural ageing process.

Little research had been carried out into the ability of over-the-counter antiageing products to treat such photo-ageing, Professor Griffiths said, but the suggestive results of his preliminary study had prompted a six-month double-blind clinical trial, involving 60 volunteers, funded by Boots. “We are giving the cream to 30 people to use on their faces and a normal moisturiser to 30 more as a placebo. At present we are about halfway through the trial, although we have not started assessing the results yet.”

The cream’s effectiveness would be assessed by looking at “before and after” photographs and examining participants’ faces for signs of sun damage such as wrinkles and moles, he added. “Boots are actually very brave to subject their product to this kind of testing. They do not need to do so on the basis of their current sales, but positive results in this trial may lead to a completely different level of scrutiny for cosmetics as medicines.”

The preliminary study involved nine people wearing a patch containing the solution on their photo-damaged forearms for 12 days. A 6 per cent formulation of the cream later revealed to be the Boots serum increased two proteins, fibrillin-1 and procollagen-1, essential for the elasticity of skin. “This may suggest a role in the general repair of skin for the peptide combination contained in the cream,” Professor Griffiths said.

Steve Barton, a skincare science advisor from Boots, said: “Dermatologists are still sceptical about the lack of published scientific evidence about the effects of skincare products, but following successful tests of the product by our own in-house team, we are confident enough in the product to test it in a double-blind clinical trial.”

The Medicines and Healthcare Products Regulatory Agency (MHRA) said that it would consider reclassifying cosmetic creams as medicines on a case-by-case basis if sufficient evidence came to light about their effects.

But Mr Barton said Protect and Perfect would be regulated as a cosmetic for the foreseeable future. “The full significance of a product’s effect on the skin may become clear and determine whether that product should be classes as a medicine or a cosmetic, but I’m still confident that we do not have a sea change in classification just yet.”

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