Retrospective evaluation of drug to drug interactions with paclitaxel use in military health.

Abstract

e24118 Background: Paclitaxel is an antineoplastic agent used in the management of multiple metastatic and non-resectable tumor types approved for ovarian, breast, AIDS-related Kaposi sarcoma, non-small cell lung, pancreatic, cervical, endometrial, and thymoma or thymic carcinoma cancer by the US Food and Drug Administration. Cytochrome P450 (CYP) 3A4 or 2C8 inducers, inhibitors, or substrates may alter paclitaxel metabolism. Because DDIs can have an effect on clinical outcomes, we aimed to identify drugs that interact with paclitaxel and describe their clinical manifestations. Methods: A retrospective analysis was performed on the health records of patients in the US Department of Defense Cancer Registry (retrieved March 2022), Comprehensive Ambulatory/Professional Encounter Records, and Pharmacy Data Transaction Service database (both retrieved October 2022). Patients’ medical history, diagnoses, and demographics were extracted and analyzed for differences in adverse effects when these agents were used alone vs concomitantly with other prescription drugs. Patients’ diagnoses and prescription drug use were extracted to compare completed vs discontinued treatment groups, identify medications commonly co-administered with paclitaxel, and evaluate DDIs with antidepressants. Results: Of 702 patients using paclitaxel, 338 completed treatments. The P value for paclitaxel discontinuation when used alone vs concomitantly or 1 drug (alone or before or after) vs combination (2 to 4 drugs) was < .001. Patients who took paclitaxel concomitantly with a greater number of prescription drugs had a higher rate of treatment discontinuation than those who received fewer medications. Patients in the completed group received 9 to 56 prescription drugs, and those in the discontinued group were prescribed 6 to 70. Those who discontinued treatment had more diagnosed medical issues than those who completed treatment. Conclusions: This review cannot conclude that concomitant use with prescription drug(s) resulted in paclitaxel discontinuation. There were no significant DDIs determined between paclitaxel and antidepressants.[Table: see text]