The US Food and Drug Administration has approved AstraZeneca's lipodystrophy drug Myalept but as expected, it will be available to fewer patients than the company had originally hoped.

Specifically, the agency has given the green light to Myalept (metreleptin) as replacement therapy to treat the complications of leptin deficiency in patients with congenital or acquired generalised lipodystrophy, a lack of fat tissue. The thumbs-up for this rare condition follows advice issued in December by the FDA's Endocrinologic and Metabolic Drugs Advisory Committee.

That panel voted 11-1 in favour of the use of Myalept for both types of generalised lipodystrophy but 10-2 against recommending the therapy for patients with metabolic disorders associated with partial lipodystrophy. The FDA has gone along with the advisory committee, thus considerably restricting the drug's potential.

The agency noted that because of risks associated with the development of neutralising antibodies and lymphoma, Myalept is available only through a risk evaluation and mitigation strategy programme. It is also requiring seven post-marketing studies and requested a further eight trials.

Myalept was developed by Amylin which was subsequently acquired by Bristol-Myers Squibb  and then partnered with AstraZeneca as part of a diabetes joint venture between the two major drugmakers. The Anglo-Swedish company completed its purchase of B-MS' interest in the JV earlier this month.