Clinical trial: a dose-response study of fospropofol disodium for moderate sedation during colonoscopy

An effective agent is needed that provides rapid onset of sedation and quick recovery for patients undergoing colonoscopy.

To assess the efficacy and safety of fospropofol disodium in providing sedation in patients undergoing colonoscopy.

A randomized, double-blind, multicentre trial evaluated 127 adult patients who received fospropofol (2, 5, 6.5 or 8 mg/kg) or midazolam 0.02 mg/kg following pre-treatment with fentanyl. Supplemental doses of study medication were allowed to reach a Modified Observer's Assessment of Alertness/Sedation scale score < or =4. Efficacy end points included sedation success, measures of clinical benefit, sedation, and recovery as well as patient- and doctor-rated satisfaction.

Fospropofol produced a significant dose-dependent increase in sedation success from 24% (2 mg/kg), 35% (5 mg/kg) and 69% (6.5 mg/kg) to 96% (8 mg/kg; P < 0.001). There were also dose-dependent trends for time to sedation, requirements for alternative sedative medication, supplemental doses of sedative and fentanyl, time to ready for discharge and doctor-rated satisfaction scores. Fospropofol was well tolerated, with most adverse events mild-to-moderate in severity.

The 6.5 mg/kg dose of fospropofol provides the ideal balance of efficacy and safety for patients undergoing colonoscopy and has been selected for phase 3 clinical development.