- Patients receiving medications or substances with the potential to affect the activity the activity or pharmacokinetics of CCI-779 (temsirolimus), such as CYP3A4 substrates, inducers, or inhibitors may be enrolled at the discretion of the investigator; however, consideration should be given to stopping or switching to non-interfering agents if clinically feasible; in all cases, the use of these agents should be listed on the concomitant medication record