VANCOUVER – Patients who underwent injections of ATX-101 (Kybella) for treatment of an unsightly double chin reported a high degree of satisfaction with the results, according to a pooled analysis of four large, double-blind, placebo-controlled, phase III trials.
Two of the trials were conducted in North America, two were conducted in Europe. The patient-reported outcomes were consistently favorable across this wide geographic and cultural range, Dr. Nowell Solish reported at the World Congress of Dermatology.
ATX-101 is a proprietary formulation of nonhuman, nonanimal deoxycholic acid. Injected directly into the excess submental fat also known as a double chin, it causes lysis of adipocytes. Earlier this year the product became the first Food and Drug Administration–approved nonsurgical treatment for double chins.
Although physician-scored ratings of improvement played a key role in obtaining regulatory approval, Dr. Solish, a dermatologist at the University of Toronto, focused on the patient-reported outcomes, which are particularly germane given that this is an aesthetic treatment.
The pooled analysis was restricted to 315 placebo-treated controls and 413 participants who received the FDA-approved dosing regimen, in which a single treatment consists of up to 50 injections of 0.2 mL each, placed 1 cm apart, which translates to 2 mg/cm2. The pooled analysis included patients who had up to four treatment sessions placed at least 1 month apart. All subjects had to have moderate to severe excess submental fat and dissatisfaction with the appearance of their face and chin.
A variety of outcome measures collectively painted a picture of improved patient satisfaction with face and chin appearance, significant psychological improvement, and satisfaction with the therapy itself.
For example, on the Subject Self-Rating Scale, which assesses satisfaction with face and chin appearance, 70% of North American and 72% of European ATX-101–treated patients were classified as satisfied as defined by a score of 4 or more on the 0-6 scale 12 weeks after the final treatment. This was the case for only 27% of North American and 32% of European placebo-treated controls.
On the 0-10 Patient-Response Submental Fat Impact Scale, which assesses the psychological impact of the visual appearance of the chin as well as emotional self-perception, average scores in the active treatment arms improved by 3-4 points from a baseline of 7, compared with 1- to 2-point improvements in the control groups.
Roughly 80% of patients who received the chin-fat buster in the double-blind studies declared themselves to be “a little,” “moderately,” or “extremely” satisfied with the posttreatment definition between their chin and neck as well as with the treatment itself, as did 25%-45% of controls.
Pain, burning, swelling, and/or numbness occurred in 60%-84% of ATX-101–treated patients. These adverse events were mostly mild in intensity and short lived.
The pooled analysis was sponsored by Kythera Biopharmaceuticals, which markets ATX-101 as Kybella. Dr. Solish reported serving as a consultant to Allergan, which in June announced a definitive agreement to acquire Kythera.