A Phase 1, Double-Blind, Placebo-Controlled, Dose-Ranging Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamic Effects of Local Muscle Injections of ACE-083 in Healthy Postmenopausal Women

ACE-083 is a molecule that has been shown to increase skeletal muscle mass in animals and, therefore, has potential utility in certain diseases that affect skeletal muscle. This initial study in healthy human subjects will help determine the properties of ACE-083 (safety, tolerability, drug absorption and biologic activity), following local administration into skeletal muscle, in advance of clinical trials in patients. The study will consist of up to 7 planned groups of 8 or 9 subjects each. Subjects in each cohort will be randomized to receive either ACE-083 or placebo. ACE-083 (or placebo) will be administered locally into the right quadriceps (thigh) muscle or right tibialis anterior (lower leg) muscle. Subjects will receive a total of either one dose (on Day 1) or two doses (on Day 1 and Day 22). Each dose administered could include up to 4 injections of study drug into pre-defined locations in the muscle. A Safety Review Team (SRT) will review blinded, preliminary data from each treatment group to make recommendations regarding escalation to the next treatment group. Subjects will be assessed for safety throughout the treatment and follow-up periods. Follow-up visits will occur over 12 weeks following the last dose of study drug.