Nutropin DepotTM [somatropin (rDNA origin) for injectable
suspension] is a long-acting dosage form of recombinant human growth hormone
(rhGH). Somatropin has 191 amino acid residues and a molecular weight
of 22,125 daltons. The amino acid sequence of the product is identical
to that of pituitary-derived human growth hormone. The protein is synthesized
by a specific laboratory strain of E. coli as a precursor consisting
of the rhGH molecule preceded by the secretion signal from an E. coli
protein. This precursor is directed to the plasma membrane of the cell.
The signal sequence is removed and the native protein is secreted into
the periplasm so that the protein is folded appropriately as it is synthesized.
Somatropin is a highly purified preparation. Biological potency is determined
using a cell proliferation bioassay.
The Nutropin Depot formulation consists of micronized particles of rhGH
embedded in biocompatible, biodegradable polylactide-coglycolide (PLG)
microspheres. Nutropin Depot is packaged in vials as a sterile, white
to off-white, preservative-free, free-flowing powder. Before administration,
the powder is suspended in Diluent for Nutropin Depot (a sterile aqueous
Each 13.5 mg 3 cc single-use vial of Nutropin Depot contains 13.5
mg somatropin, 1.2 mg zinc acetate, 0.8 mg zinc carbonate, and 68.9 mg
Each 18 mg 3 cc single-use vial of Nutropin Depot contains 18
mg somatropin, 1.6 mg zinc acetate, 1.1 mg zinc carbonate, and 91.8 mg
Each 22.5 mg 3 cc single-use vial of Nutropin Depot contains 22.5
mg somatropin, 2.0 mg zinc acetate, 1.4 mg zinc carbonate, and 114.8 mg
Each dosage size contains an overage of rhGH microspheres to ensure delivery
of labeled contents.
Each 1.5 mL single-use vial of Diluent for Nutropin Depot contains
30 mg/mL carboxymethylcellulose sodium salt, 1 mg/mL polysorbate 20, 9
mg/mL sodium chloride, and sterile water for injection; pH 5.8-7.2.