KYTHERA Biopharmaceuticals Presents Positive Data from Phase IIb Study with ATX-101 Demonstrating Reduction of Submental Fat

-Results demonstrate statistically significant reduction in submental fat on objective measurement, clinician and patient ratings-

LOS ANGELES--()--KYTHERA Biopharmaceuticals, Inc. (KYTHERA) presented results from a third Phase II clinical study with ATX-101, a first-in-class adipolytic agent that is under investigation for the reduction of submental (‘under the chin’) fat. The Phase IIb study showed ATX-101 was well-tolerated and demonstrated statistically significant efficacy (p<0.05) as assessed by all measures: a validated clinician scale, patient reported outcome (PRO) scale, and Magnetic Resonance Imaging (MRI).

Patricia S. Walker, MD, PhD, KYTHERA’s Chief Medical Officer, presented the study results in the Aesthetic Innovations Segment at the 9th Annual South Beach Symposium™ in Miami, FL on Saturday, February 19, 2011.

One hundred twenty-nine subjects were randomized in a double-blind, placebo-controlled, dose-ranging study conducted across 10 dermatology and plastic surgery centers in the United States (ATX-101-09-15). Subjects received one of two dosing regimens of ATX-101 (1 mg/cm2 or 2 mg/cm2) or placebo, administered monthly for up to 5 months into the submental area. Clinician assessments were performed at all treatment visits and 4 and 12 weeks after the last treatment visit (week 24 and week 32, respectively). Subject self-assessments and MRI assessments were performed at baseline, treatment visit 5 (week 16) and 12 weeks after the last treatment visit (week 32).

In this study, the 2 mg/cm2 proved to be the more efficacious dose and yielded a statistically significant reduction of unwanted submental fat compared to placebo as measured by physician assessment (p=0.001 and p=0.003, week 24 and week 32, respectively). Evidence of improvement was observed at 1 mg/cm2, indicating that a dose response exists between the two ATX-101 regimens. Physician assessment was performed using a validated, 5-point Clinician-Reported Submental Fat Rating Scale (CR-SMFRS). In addition, the 2 mg/cm2 dose group yielded a statistically significant reduction of submental fat as measured by subject assessment (p<0.05, week 16 and week 32). Subjects assessed submental fat using a 5-point Patient Reported Outcomes (PRO) tool, the Patient-Reported Submental Fat Rating Scale (PR-SMFRS).

“The results from this study are exciting and indicate the potential of ATX-101 as an effective and well-characterized treatment for the aesthetic reduction of small volumes of fat,” said Joel Schlessinger, MD, a board-certified dermatologist and cosmetic surgeon in private practice in Omaha, Nebraska and an investigator in this study. “There are currently no FDA-approved non-surgical treatment modalities for the reduction of fat under the chin. ATX-101 may represent a breakthrough for patients who are seeking a minimally-invasive treatment option for the reduction of unwanted localized submental fat.”

In addition to subject and clinician evaluations, subjects were assessed using MRI to objectively quantify fat volume. The 2 mg/cm2 dose group achieved statistically significant reduction in submental fat volume as measured from baseline vs. placebo by MRI (p=0.045 and p=0.004, week 16 and week 32, respectively).

A statistically significant difference versus placebo was also demonstrated on additional PRO measures, including instruments measuring subject satisfaction, patient impact and subject ratings of chin attractiveness.

“We are highly encouraged by these study results,” said Patricia Walker, MD, PhD. “Meaningful clinical reductions in submental fat by physician and subject assessments have now been observed in three Phase II trials, including this study, which achieved additional statistical significance on an objective and quantifiable endpoint. We believe these data, along with the other phase II trials completed to date support proceeding into Phase III clinical development to further confirm the safety and efficacy profile of ATX-101.”

In this study, ATX-101 was well-tolerated. The most common adverse events were mild swelling, pain, numbness, bruising and induration. These adverse events were limited to the injection site, most were temporally associated with treatment and resolved within the 28-day treatment interval. No systemic treatment-related adverse events were reported.

Additional Phase IIb study results are expected to be presented at the upcoming Skin Disease Education Foundation 35th Hawaii Dermatology Seminar™ to be held March 13-18, 2011 in Maui, Hawaii. Full results from this study will also be published in an appropriate peer-reviewed journal.

About ATX-101

ATX-101 is a first-in-class injectable drug being studied for the reduction of small volumes of fat, including submental fat. It is based on an endogenous molecule with unique features including selectivity for adipocytes and rapid clearance. This minimally invasive procedure, done with little or no anesthetic, has the promise to yield consistent and meaningful clinical results. Clinical studies to date have demonstrated that ATX-101 is well-tolerated and may effectively reduce localized fat in the submental area. Three randomized, double-blind, placebo-controlled, Phase II studies with ATX-101 in the reduction of submental fat and four Phase I studies (pharmacokinetic, histology, lipid and tolerability) have been successfully completed.

About Submental Fat (SMF)

Submental fat is localized subcutaneous fat located immediately beneath the chin and jawline. In the rapidly growing market of minimally invasive, non-surgical facial rejuvenation, the reduction of facial fat to restore and reshape the jawline remains one of the largest unmet patient needs. According to a recent national, multi-center, clinical evaluation of more than 385 BOTOX® and dermal filler patients, 78% of patients had a measurable excess of submental fat. Currently, there are no FDA approved drugs to reduce excess localized fat.

About KYTHERA Biopharmaceuticals, Inc.

KYTHERA Biopharmaceuticals, Inc. is a privately held, clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of novel prescription products for the aesthetic market. KYTHERA has an innovative pipeline, with its lead program in adipolysis (ATX-101) projected to start US Phase III trials in 2011. The company also has active research programs in hair and fat biology, pigmentation modulation and facial contouring. Find more information at


KYTHERA Biopharmaceuticals, Inc.
Erica Bazerkanian, 805-300-9289


KYTHERA Biopharmaceuticals, Inc.
Erica Bazerkanian, 805-300-9289