Effects of Human Leptin Replacement

This study will test the hypothesis that leptin contributes to the regulation of the dynamics of human endocrine function.

The study aims to elucidate the role of leptin in the regulation of human endocrine function approached by a carefully designed, prospective clinical study of the rapidly-sampled dynamics of endocrine rhythms during the course of leptin-replacement treatment in the only three adult individuals identified in the world so far who are leptin-naive due to a functional leptin gene mutation. A study of leptin-naive subjects avoids all confounding factors and pitfalls, because the only bioactive leptin to which they will be exposed is the exogenously administered recombinant protein. Thus, this proposal will permit us to ascertain the endocrine effects of human leptin.

Participants with congenital leptin deficiency will receive the Recombinant methionyl human leptin intervention subcutaneously, once a day with a dose of 0.02 to 0.04 mg/kg (adjusted according to weight loss).

Recombinant methionyl human leptin, subcutaneous, once a day, 0.02 to 0.04 mg/kg (adjusted according to weight loss), indeterminate duration.

Inclusion Criteria: Congenital leptin deficiency (these are only 3 adult individuals in the world that have been identified as leptin-naïve thus far). Exclusion Criteria: Pregnant, trying to become pregnant, breast-feeding an infant or sexually active women, not using contraception. Subjects with hemoglobin levels below 12 g/dl. Subjects whose body contains a ferromagnetic implanted device that might produce a safety hazard during fMRI.

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