A phase 1 study of the cholecystokinin (CCK) B antagonist L-365,260 in human subjects taking morphine for intractable non-cancer pain.

To investigate the safety and tolerability of L-365,260 in human subjects taking morphine for intractable pain. An open label study of nine adult subjects. Two doses of L-365,260 were administered to all subjects separated by a 4 h interval (three received 10 mg, three 30 mg and three 60 mg). Haemodynamic and respiratory variables were recorded from immediately prior to first drug administration to T + 600 min. In addition, continuous electrocardiogram (ECG) monitoring and serial 12 lead ECGs were recorded along with pain and side effect measurements. No major side effects were observed. L-365,260 was well tolerated. No abnormalities in blood pressure, heart rate, respiratory rate or ECG measurements were recorded. Minor side effects were observed. L-365,260 can be safely administered at the doses investigated to human subjects receiving morphine for intractable pain.