SOMAVERT contains pegvisomant for injection, an analog of human growth hormone (GH) that has been structurally altered to act as a GH receptor antagonist.

Pegvisomant is a protein of recombinant DNA origin containing 191 amino acid residues to which several polyethylene glycol (PEG) polymers are covalently bound (predominantly 4 to 6 PEG/protein molecule).The molecular weight of the protein of pegvisomant is 21,998 Daltons. The molecular weight of the PEG portion of pegvi-somant is approximately 5000 Daltons. The predominant molecular weights of pegvisomant are thus approximately 42,000,47,000,and 52,000 Daltons. The schematic shows the amino acid sequence of the pegvisomant protein (PEG polymers are shown attached to the 5 most probable attachment sites).Pegvisomant is synthesized by a specific strain of Escherichia coli bacteria that has been genetically modified by the addition of a plasmid that carries a gene for GH receptor antagonist. Biological potency is determined using a cell proliferation bioassay.

SOMAVERT is supplied as a sterile, white lyophilized powder intended for subcutaneous injection after reconstitution with 1 mL of Sterile Water for Injection, USP. SOMAVERT is available in single-dose sterile vials containing 10,15,or 20 mg of pegvisomant protein (approximately 10,15,and 20 U activity, respectively).Vials containing 10, 15, and 20 mg of pegvisomant protein correspond to approximately 21,32,and 43 mg pegvisomant, respectively. Each vial also contains 1.36 mg of glycine,36.0 mg of mannitol,1.04 mg of sodium phosphate dibasic anhydrous, and 0.36 mg of sodium phosphate monobasic monohydrate.

SOMAVERT is supplied in packages that include a plastic vial containing diluent. Sterile Water for Injection, USP, is a sterile, nonpyrogenic preparation of water for injection that contains no bacteriostat, antimicrobial agent, or added buffer, and is supplied in single-dose containers to be used as a diluent.

Bookmark this page: