- Gonadotropin-releasing hormone antagonist (Cetrorelix) therapy fails to protect nonhuman primates (Macaca arctoides) from radiation-induced spermatogenic failure. Boekelheide, K., Schoenfeld, H.A., Hall, S.J., Weng, C.C., Shetty, G., Leith, J., Harper, J., Sigman, M., Hess, D.L., Meistrich, M.L. J. Androl. (2005)