Impact of a specialty pharmacy case management service on adherence in patients receiving oral antineoplastic agents

Background Patients receiving treatment with oral antineoplastic agents encounter several barriers to adherence, which may include high medication costs, limited access to specialty medications, severe adverse effects, complex medication regimens, and special handling precautions. Medication nonadherence not only reduces the efficacy of drug therapy but also has the potential to increase healthcare expenditures due to disease-related hospitalizations. Although several previous studies have examined patient adherence to oral antineoplastic agents, few have examined the impact of a specialty pharmacy case management service. Methods Patient adherence to oral antineoplastic agents was evaluated through a retrospective analysis of pharmacy claims data and medical chart reviews. The medication possession ratio (MPR) was used to quantitatively measure adherence during two 6-month intervals, prior to and following the implementation of a case management service. Patients with an MPR greater than or equal to 0.8 were categorized as adherent, while those with an MPR less than 0.8 were categorized as non-adherent. Results During the first 6-month interval prior to implementation of the case management service (n = 40), a cumulative average MPR of 0.922 was observed. Following implementation of the case management service (n = 56), a non-statistically significant (p = 0.199) increase in MPR to 0.941 was identified. For patients categorized as non-adherent, a nonstatistically significant (p = 0.214) decrease from 15% to 7% was identified following the introduction of the case management service. Conclusion Study results from this retrospective review indicate that case management services provided through an outpatient specialty pharmacy may have the potential to improve patient adherence to oral antineoplastic agents.