Topokine Therapeutics has initiated dosing in a Phase 2, randomised controlled clinical trial of XAF5 Gel for reduction of excess submental fat, commonly referred to as ‘double chin’. XAF5 Gel is a proprietary skin formulation of a compound already known to reduce fat around the human eye. Study participants are applying XAF5 Gel or placebo once per night to skin under the chin.

‘Patients are increasingly interested in non-invasive therapies to rejuvenate the face,’ said Jeffrey S. Dover, MD, FRCPC, a ┬ádermatologist and member of the Topokine’s Scientific Board of Advisors. ‘If approved, XAF5 Gel would provide a convenient topical medication that reduces submental fat.’

XAF5 is a small molecule that induces a G protein-coupled cascade in adipocytes to reduce cellular lipid content and differentiation. Daily administration of XAF5 reduces fat around the human eye and in five laboratory models. The technology was first conceived by ophthalmologists at the Massachusetts Eye and Ear Infirmary/Harvard Medical School Department of Ophthalmology.

The Phase 2 study follows positive data from a 6-week Phase 1 clinical trial completed in April 2013. In that randomised, double-blind, placebo-controlled study, 32 healthy men and women applied XAF5 Gel or placebo once per night to a 100 cm2 area of abdominal skin. The study met its pre-specified primary safety and tolerability endpoint at all doses. The only side-effects were mild, temporary skin redness or itch, which occurred at similar rates with placebo. Exploratory CT scans showed a dose-dependent reduction in fat volume under treated skin as compared to contralateral untreated skin.

‘We are excited to advance our XAF5 Gel programme into Phase 2,’ said Topokine’s Chief Scientific Officer, Michael Singer, MD, PhD. ‘Our research shows that patients would prefer a topical fat-reducing medication over therapies that cut or puncture the skin, which are the only treatments currently available. The submental region is one of several body areas that we plan to target.’