Pharmacia Corporation announced that the U.S. Food and Drug Administration (FDA) has approved Somavert (pegvisomant for injection) for the treatment of acromegaly in patients who have had an inadequate response to surgery and/or radiation therapy and/or other medical therapies, or for whom these therapies are not appropriate. The goal of treatment is to normalize serum IGF-I levels.

Acromegaly is a serious, life-shortening disease triggered by over-secretion of growth hormone, most often caused by a pituitary tumor. This excess of growth hormone leads to overproduction of a second hormone, IGF-I (insulin-like growth factor-l), which contributes to the disabling symptoms and the long-term health problems associated with the disorder. Patients with acromegaly often suffer from headache, excessive sweating, soft-tissue swelling, joint disorders and, perhaps most striking, a progressive coarsening of facial features and enlargement of the hands, feet and jaw. Patients with acromegaly face a mortality rate two to four times higher than the average person, due to such serious long-term complications as heart and respiratory disease, diabetes mellitus and some forms of cancer.

Somavert is the first in a new class of medicines called growth hormone receptor antagonists and the only medicine designed to specifically block the effects of excess growth hormone in acromegaly. It will be available in the US by prescription within the next few weeks. Somavert was approved by the European Commission in November 2002.

Somavert was studied in a fixed-dose, randomized clinical trial and in a long-term, open-label, dose-adjusted study in patients with acromegaly. In the pivotal study, Somavert normalized IGF-I levels in up to 82 percent of patients, and in the long-term study, Somavert normalized concentrations of IGF-I in 92 percent of patients. IGF-I level is a biochemical measure of the severity of acromegaly.

The number of patients diagnosed with acromegaly in the US, Europe and Japan is in the tens of thousands. Experts believe the prevalence may be higher, as diagnosis is often delayed for up to 15 years after symptoms begin. Traditional treatments for acromegaly include surgery to remove the pituitary tumor, radiation therapy and pharmaceutical treatments.

In clinical studies, elevations of liver tests (ALT and AST) greater than ten times the upper limit of normal were reported in two patients (0.8%) exposed to Somavert. Serial monitoring of liver tests is necessary when beginning and during therapy with Somavert. The most commonly reported adverse events with Somavert occurring in at least ten percent of patients and at frequencies greater than placebo were infection, pain, diarrhea, nausea, flu syndrome, abnormal liver function tests, and injection-site reactions. The majority of reported adverse events were of mild to moderate intensity and limited duration. Somavert is contraindicated in patients with hypersensitivity to any of its components. The stopper on the vial of Somavert contains latex.