Pegvisomant, sold under the brand name Somavert, is a growth hormone receptor antagonist used in the treatment of acromegaly.

[1][2][3] It is primarily used if the pituitary gland tumor causing the acromegaly cannot be controlled with surgery or radiation, and the use of somatostatin analogues is unsuccessful, but is also effective as a monotherapy.

[1][2] Side effects of pegvisomant include reactions at the injection site, swelling of the limbs, chest pain, hypoglycemia, nausea and hepatitis.

[6] Pegvisomant was discovered at Ohio University in 1987 by Distinguished Professor John Kopchick and graduate student Wen Chen at the Edison Biotechnology Institute.

[7] Pegvisomant is a protein containing 191 amino acid residues to which several polyethylene glycol polymers have been covalently bound in order to slow clearance from the blood.