DESCRIPTION Saizen® [somatropin (rDNA origin) for injection] is a human growth hormone produced by recombinant DNA technology. Saizen® has 191 amino acid residues and a molecular weight of 22,125 daltons. Its amino acid sequence and structure are identical to the dominant form of human pituitary growth hormone. Saizen® is produced by a mammalian cell line (mouse C127) that has been modified by the addition of the human growth hormone gene. Saizen®, with the correct three-dimensional configuration, is secreted directly through the cell membrane into the cell-culture medium for collection and purification. Saizen® is a highly purified preparation. Biological potency is determined by measuring the increase in body weight induced in hypophysectomized rats. Saizen® is a sterile, non-pyrogenic, white, lyophilized powder intended for subcutaneous or intramuscular injection after reconstitution with Bacteriostatic Water for Injection, USP (0.9% Benzyl Alcohol). The reconstituted solution has a pH of 6.5 to 8.5. Saizen® is available in 5 mg and 8.8 mg vials. The quantitative composition per vial is: 5 mg vial: Each vial contains 5 mg somatropin, 34.2 mg sucrose and 1.16 mg O-phosphoric acid. The pH is adjusted with sodium hydroxide or O-phosphoric acid. 8.8 mg vial: Each vial contains 8.8 mg somatropin, 60.2 mg sucrose and 2.05 mg O-phosphoric acid. The pH is adjusted with sodium hydroxide or O-phosphoric acid. The diluent is Bacteriostatic Water for Injection, USP containing 0.9% Benzyl Alcohol added as an antimicrobial preservative. Saizen® is also available in the click.easy® reconstitution device. The quantitative composition per vial contained in the click.easy® reconstitution device is: 8.8 mg vial contained in the click.easy® device: Each vial contains 8.8 mg somatropin, 60.2 mg sucrose and 2.05 mg O-phosphoric acid. The pH is adjusted with sodium hydroxide or O-phosphoric acid. 4 mg vial contained in the click.easy® device: Each vial contains 4 mg somatropin, 27.3 mg sucrose and 0.9 mg O-phosphoric acid. The pH is adjusted with sodium hydroxide or O-phosphoric acid. The diluent in the click.easy® device contains 0.3% (w/v) metacresol in Sterile Water for Injection added as an antimicrobial preservative. The reconstituted solution has a pH of 6.5 to