Information Testolone (RAD140) Testolone (RAD140) is a potent, orally bioavailable, nonsteroidal selective androgen receptor modulator with Ki value of 7 nM as well as good selectivity over other steroid hormone nuclear receptors. Targets Androgen Receptor 7 nM(Ki) In vivo The stability of RAD140 is high (t 1/2 > 2 h) in incubations with rat, monkey, and human microsomes, and it also has good bioavailability in rats (F = 27−63%) and monkeys (65−75%).