serostim serostim serostim (recombinant dna somatropin) is serono's brand name prescription drug form of synthetic growth hormone, marketed for hiv-associated wasting. in december 2007, the u.s. district court of massachusetts - in a class-action lawsuit that involved merck serono and serostim - fined serono a total of $704 million in criminal and civil liabilities for enacting "illegal schemes to promote, market and sell its drug."