To assess the tolerability and preliminary safety of subcutaneous (SC) dosing of r-metHULeptin as compared with placebo in subjects across a range of doses and body mass indexes. This study is a 24-week, randomized, double-blind, placebo controlled study with individuals being divided into four dose cohorts. The study will be divided into 2 parts: part A, weeks 1 to 4 (pharamcokinetics) and part B, weeks 5 to 24 (safety, tolerability, and preliminary efficacy).