Prescriber adherence to antiemetic guidelines with the new agent trifluridine-tipiracil

Background In 2015 alone, the US Food and Drug Administration approved 18 cancer drugs, but to our knowledge, few studies, if any, have examined prescribers' adherence to antiemetic guidelines as new chemotherapy agents become available. This issue is important because poor adherence to antiemetic guidelines has been shown in previous studies to have a negative impact on the control of nausea and vomiting. Here we report on antiemetic practices and outcomes for trifluridine-tipiracil, a drug newly approved in 2015. Objective To test the hypothesis that patients prescribed a newly available chemotherapy agent, trifluridine-tipiracil, are at risk for chemotherapy-induced nausea and vomiting because of providers' poor adherence to antiemetic guidelines. Methods All patients who received their first dose of trifluradine-tipiracil for metastatic colon cancer in 2015 were included in this retrospective, single-institution study of pretreated patients. The study time frame was the 2015 calendar year: 9 months before the drug was approved in September 2015, when patients received the medication through a compassionate-use program, and the 3 months immediately after drug approval. First-cycle antiemetic prescribing was examined for adherence to National Comprehensive Cancer Network Guidelines (v1.2015) and categorized as guideline adherent, non-guideline-adherent/aggressive (received more prophylaxis than called for), and non-guideline-adherent/less aggressive (including no antiemetics). Results Of the 44 patients in this study, 28 (64%) had had nausea and vomiting with previous chemotherapy. With the first cycle of trifluridine-tipiracil, 25 patients (57%; 95% confidence interval [CI]: 42%, 70%) were prescribed prophylactic antiemetics in a guideline-adherent manner; 15 (34%; 95% CI: 22%, 49%) in a non-guideline-adherent/aggressive manner; and 4 (9%; 95% CI: 4%, 21%) in a non-guideline-adherent/less aggressive manner. In guideline-adherent patients, rates of nausea and vomiting were 52% and 24%, respectively. In non-guideline-adherent/aggressive patients, those rates were 33% and 27%, respectively. In both the aforementioned groups, a total of 2 patients received interim care for nausea and vomiting. No nausea or vomiting was reported among non-guideline-adherent/less aggressively managed patients. Limitations Single-institution, retrospective study of a small group of patients Conclusions Poor adherence to antiemetic guidelines was common. However, because adherence was not consistently associated with better control of nausea and vomiting, clinical judgment should complement guideline adherence when prescribing trifluridine-tipiracil and other newly approved cancer drugs.