First human exposure to FSH-CTP in hypogonadotrophic hypogonadal males

BACKGROUND: This is the first report of human exposure to the novel compound follicle stimulating hormone(FSH)-C-terminal peptide (CTP) ‘FSH-CTP’ (Org 36286), a long-acting recombinant FSH like substance, consistingof the α-subunit of human FSH and a hybrid β-subunit. The latter is composed of the β-subunit of human FSHand the C-terminus part (CTP) of the β-subunit of human chorionic gonadotrophin (HCG). METHODS: In thisphase I, non-blind, multi-centre study, 13 hypogonadotrophic hypogonadal male subjects were enrolled to test thesafety of FSH-CTP in terms of antibody formation in humans. Furthermore, the pharmacokinetic profile of thisnew compound was determined. Subjects were injected four times with 15 µg FSH-CTP with an interval of ∼4weeks between each injection. RESULTS: No drug related (serious) adverse events occurred. No antibodies againstFSH-CTP or chinese hamster ovary (CHO)-cell derived proteins were detected and measurement of local tolerancedemonstrated that s.c. administration of FSH-CTP is well tolerated and no increase in intensity of injection-siteresponses was observed after repeated exposure to FSH-CTP. After the first and third injection, FSH-CTP serumconcentrations were determined. Overall mean ( SD) C