Polypharmacy, wrong prescriptions persist in older cancer patients on immunotherapy

Inappropriate prescription practices and polypharmacy remain a burden in patients treated with immune checkpoint inhibitors (ICIs), a study has found.

“These issues pointed out the need for improved general medical care and attention for better comedication management in ICI-treated patients,” the investigators said.

This study sought to assess polypharmacy frequency and drug-drug interactions in 70 older patients (≥65 years) with advanced cancer on ICI treatment. Polypharmacy was defined as regular use of five or more drugs.

The investigators used the START/STOPP Criteria Version 2 for the potentially inappropriate medications (PIM) and potential prescription omissions (PPO) and the Medscape Drug Interaction Checker for potential drug-drug interactions.

The median number of drugs taken regularly by patients was six, with polypharmacy seen in 77.1 percent. Patients aged >75 years (p=0.028) and those using opioids (p=0.048) showed a significantly higher risk of polypharmacy. Half of the patients (50 percent) had category D or X interactions.

Higher Charlson Comorbidity Index (CCI) was significantly associated with an increased risk for drug interactions (CCI ≤10 vs >10; p=0.017). PIMs and PPOs were found in 44.3 percent and 68.6 percent of patients, respectively.

In patients using seven or more drugs, overall survival and immune-related adverse events were similar, but the risk of acute kidney injury was substantially elevated (hazard ratio, 4.667; p=0.038).

“Polypharmacy is a common problem in older cancer patients, although the data about polypharmacy and potentially inappropriate prescription practices is limited in patients treated with ICIs,” the investigators said.