The US Food and Drug Administration has given the green light to Leo Pharma's skin cancer gel Picato, the Danish firm's first major US approval across the pond in about 20 years.

Picato (ingenol mebutate) has been approved for actinic keratoses (AK) on the face, scalp, trunk and extremities. AK, which often appear as red, scaly skin lesions, affect more than 58 million Americans, according to the Skin Cancer Foundation.

Moreover, they are precursors to skin cancer and can progress to squamous cell carcinoma; a study has shown that around 65% of cases of the latter may begin as AK.

The FDA approval for Picato is based on data from four Phase III studies in over 1,000 people showing that when applied once-daily for two (trunk and extremities) or three (face and scalp) consecutive days, the gel is significantly more effective than placebo at clearing AK.

Leo quoted Mark Lebwohl, head of dermatology at Mount Sinai Medical Center in New York, as saying that "since there is no way to predict which AK will advance to skin cancer, early detection and treatment of lesions are critical". He added that "what makes this new therapy particularly exciting is the two or three-day course of treatment".

Taking up that point, Leo chief executive Gitte Aabo noted that existing topical therapies require several weeks or months of treatment, so the shorter duration "will be well received by both patients and clinicians". She added that the approval of Picato, which is derived from the Euphorbia peplus plant, is "another important step in Leo’s goal of becoming one of the world’s leading dermatology companies".