Myalept

Description

Myalept (metreleptin) is a recombinant human leptin analog indicated as an adjunct to diet as replacement therapy to treat the complications of leptin deficiency in patients with congenital or acquired generalized lipodystrophy. It functions by binding to and activating the human leptin receptor (ObR), thereby regulating metabolic processes, improving glycemic control, and lipid metabolism. Myalept is administered via subcutaneous injection and is available in 11.3 mg vials of lyophilized powder for reconstitution.

Directions

Myalept is administered once daily via subcutaneous injection. The recommended starting dose varies based on body weight:

• For patients weighing =40 kg: 0.06 mg/kg/day, with potential adjustments of 0.02 mg/kg to a maximum of 0.13 mg/kg/day.

• For males weighing >40 kg: starting dose of 2.5 mg/day, adjustable in increments of 1.25 mg to a maximum of 10 mg/day.

• For females weighing >40 kg: starting dose of 5 mg/day, adjustable in increments of 1.25 mg to a maximum of 10 mg/day.

Reconstitution should be performed using Bacteriostatic Water for Injection (BWFI) or preservative-free sterile Water for Injection (WFI). Patients should be instructed on proper injection techniques, including site rotation to minimize local injection site reactions.

Ingredients

The active ingredient in Myalept is metreleptin, a recombinant human leptin analog. Excipients include sucrose, polysorbate 20, and phosphate buffer to stabilize the formulation.

Contraindications

Myalept is contraindicated in patients with:

• General obesity not associated with congenital leptin deficiency.

• Known hypersensitivity to metreleptin or any of its components.

Additionally, the safety and effectiveness of Myalept for the treatment of complications of partial lipodystrophy or liver disease, including nonalcoholic steatohepatitis (NASH), have not been established. Myalept is not indicated for use in patients with HIV-related lipodystrophy or in those with metabolic disease, including diabetes mellitus and hypertriglyceridemia, without concurrent evidence of generalized lipodystrophy.

Cautions

• Risk of Anti-metreleptin Antibodies: Anti-metreleptin antibodies with neutralizing activity have been identified in patients treated with Myalept. These antibodies could inhibit endogenous leptin action and/or result in loss of Myalept efficacy. Severe infections and/or worsening metabolic control have been reported. Patients developing severe infections or showing signs of loss of efficacy should be tested for these antibodies.

• Risk of Lymphoma: T-cell lymphoma has been reported in patients with acquired generalized lipodystrophy, both treated and not treated with Myalept. Carefully consider the benefits and risks of treatment in patients with significant hematologic abnormalities and/or acquired generalized lipodystrophy.

• Hypoglycemia: There is a risk of hypoglycemia in patients on concomitant insulin or insulin secretagogues. Monitor blood glucose levels and adjust the dose of insulin or insulin secretagogues as appropriate.

• Autoimmune Disease: Use with caution in patients with autoimmune diseases due to the potential for exacerbation.

• Benzyl Alcohol Toxicity: Myalept contains benzyl alcohol when reconstituted with BWFI. The preservative benzyl alcohol has been associated with serious adverse events and death in pediatric patients, particularly in neonates and premature infants. Preservative-free WFI is recommended for use in neonates and infants.

Side Effects

Common and serious side effects of Myalept include:

• Common (=10%): Headache, hypoglycemia, decreased weight, and abdominal pain.
• Serious: Development of anti-metreleptin antibodies with neutralizing activity, risk of lymphoma, severe infections, and hypoglycemia.