somatrem somatrem somatrem, sold under the brand name protropin, is an analogue of growth hormone (gh). somatremclinical datatrade namesprotropinahfs/drugs.commicromedex detailed consumer informationatc codeh01ac02 (who) identifierscas number82030-87-3 ndrugbankdb09098 ychemspidernoneuniicu8d464edwkeggd05884 ychemblchembl1201620 nchemical and physical dataformulac995h1537n263o301s8molar mass22256.26 g·mol−1 ny (what is this?) (verify) somatrem is a recombinant human growth hormone used for the treatment of short stature due to decreased or absent secretion of endogenous growth hormone. somatrem was first marketed under the brand name protropin by genentech in 1985. it differs from endogenous growth hormone by the addition of an extra methionine at the n-terminus. somatrem has largely been replaced by somatropin, marketed by several companies including by genentech as the brand nutropin.