Tonapofylline (BG 9928) is an orally active and selective adenosine A₁ receptor antagonist with a K_i of 7.4 nM for human adenosine A₁ receptor (hA₁), which displays 915-fold selectivity versus human adenosine A_2A receptor and 12-fold selectivity versus human adenosine A_2B receptor and is used in development for the treatment of heart failure^[1][2]. IC50 & Target: Ki: 7.4 nM (Human adenosine A1 receptor)^[1] In Vivo: Tonapofylline (BG 9928) (1 mg/kg; p.o., b.i.d, days 0-6) produces sustained reductions in post-Cisplatin serum creatinine and blood urea nitrogen levels, improves body weight recovery and significant attenuation of Cisplatin-induced (5.5 mg/kg) kidney pathology scores^[3].