Quest PharmaTech Announces Positive Results From Actinic Keratosis Trial
Quest PharmaTech's 12-patient, Phase I clinical study entitled "ACP-SL017 Topical Gel: A Phase I Study for the Photodynamic Therapy of Actinic Keratosis" has met both its primary and exploratory objectives.
"We are delighted to have received, for the first time, clinical validation for our SonoLight Technology in a dermatological application," said Madi R. Madiyalakan, CEO of Quest. "Actinic Keratosis is a pre-cancerous skin condition usually caused by prolonged accumulated sun exposure which can progress to squamous cell carcinoma, a potentially life-threatening form of skin cancer, unless treated by a dermatologist or other physician. This trial successfully demonstrated that cutaneous photodynamic therapy (PDT) with SL017 appears safe and is well tolerated. In addition, our unique approach is designed to overcome some of the limitations associated with other commercially available PDT treatments for Actinic Keratosis."
Actinic Keratosis has a global incidence of approximately 10 to 15% in the Caucasian population and the American Medical Association estimates the U.S. market for the treatment of Actinic Keratosis to be about US $250 million.
The primary objective of the Phase I study, which was conducted in Canada, was to determine the cutaneous and systemic toxicity of the topically-applied photoactive drug, SL017, with and without photoactivation. The exploratory objective was to evaluate the efficacy of SL017 with and without photoactivation in the treatment of Actinic Keratosis. The study parameters employed included physician clinical assessment, patient symptomatic assessment, skin photography, blood chemistry, urinalysis, electrocardiogram and skin biopsy. The study was conducted at clinical sites in Edmonton and Montreal.
The study met all the objectives addressing the clinical safety endpoints. There were no observed clinically relevant adverse events associated with the treatment at all the concentrations (0 to 40 mg of SL017) and light doses (10 to 20 joules/cm(2)) administered. The light treatment, conveniently administered in a dermatology clinic, was well tolerated. The therapeutic potential of SL017 was evidenced by the expected (PDT) effects, such as redness, edema, occasional blisters, stinging and burning. The clinical correlates of dyskeratosis and inflammation were likewise appropriately noted on skin biopsy. Clinical and pathological results correlated very well, and conformed not only to the expected effects of PDT but also to the dosage of the drug and light energy administered. The study suggests that a 2% topical formulation of SL017 and a fluence of 20 joules/cm (2) provide expected PDT outcomes. Importantly, this Phase I study did not identify any safety concerns with respect to the parameters evaluated at the dosages of drug and light employed.
"I am encouraged by the confirmation of the topical PDT effects of SL017 and its potential for future applications in a variety of dermatological conditions including Actinic Keratosis," commented Dr. Gilles Lauzon, former Director, Division of Dermatology, University of Alberta and one of the investigators of the study.
The potential applications of cutaneous PDT also include acne, rosacea, superficial skin cancers, cutaneous T-cell lymphoma, localized scleroderma, warts, leishmaniasis and skin rejuvenation. Quest has already shown the follicular uptake of SL017 in humans; and is currently conducting a 90-patient trial addressing potential hair removal applications with results anticipated by end of this year. The Company is also evaluating the utility of SL017 for the treatment of acne in a preclinical model.