A targeted approach to reducing rates of discontinuation and dose reduction in patients receiving sorafenib or regorafenib

Background: Sorafenib and regorafenib are oral multikinase inhibitors used to treat some cancers, but adverse events for both drugs are common and often cause patients to discontinue therapy or reduce their dose within several months of initiating therapy. Pharmacists have the potential to prevent discontinuation by closely monitoring and addressing patients’ adverse reactions. Aims: To assess whether a pharmacist-initiated tailored intervention reduced patient discontinuations and dose reductions due to adverse reactions from sorafenib and regorafenib. Methods: We conducted a historically controlled intervention (initiated Aug 2017) to detect and address adverse events in patients prescribed sorafenib and regorafenib. All patients who initiated therapy after August 2017 were in the intervention group (IG); at treatment initiation, IG patients received initial pharmacist counseling and a welcome kit containing educational materials, urea based creams, therapeutic socks and pill container (sorafenib only). During the 90 days after initiating treatment, pharmacists called IG patients six times to conduct assessment questionnaires, designed to detect common adverse reactions at each interval. Pharmacists addressed adverse events by providing additional counseling, referring patients for clinic appointment or requesting ancillary medications. The comparison group (CG) patients initiated therapy between September 2016 and August 2017. CG patients only received pharmacist counseling at treatment initiation. We collected patient demographics and treatment indication, and compared how many patients discontinued or reduced dose in the IG vs the CG. Results: We assessed 33 patients (16 IG vs 17 CG). Most were female (61%) and White (88%); median age 53 years. Common indications were hepatocellular carcinoma (36%), acute myeloid leukemia (30%) and desmoid tumor (21%). In the 90 day follow-up, IG had lower rates of treatment discontinuation (13% vs 29%) and dose reduction due to side effects (13% vs 18%) than CG. Combined events of either discontinuation or dose reduction due to side effects were less frequent in the patients in the IG than the CG (25% vs 65%). Conclusions: Patients treated with sorafenib or regorafenib were less likely to discontinue therapy or reduce doses due to adverse reactions after receiving a pharmacist-led phone intervention. Findings suggest tailored phone assessments are effective in detecting and treating adverse reactions, thus enabling patients to remain on therapy longer and without dose modification.