Avoidance of drug interactions with hepatitis C treatment: Evaluation of pharmacist interventions in the specialty setting.

OBJECTIVES: Direct-acting antiviral (DAA) therapy is currently recommended for most patients chronically infected with the hepatitis C virus (HCV) by the American Association for the Study of Liver Diseases/Infectious Diseases Society of America guidelines. DAAs have significant drug interaction potential, which can lead to treatment failure and adverse drug events. The primary goal of this study is to report the number and nature of interventions made by pharmacists regarding drug interactions in patients using DAA therapy and to estimate the cost avoidance of averting potential DAA treatment failures. METHODS: The patients in this cohort were identified through the pharmacy's electronic medical record if they were at least 18 years old while having filled a prescription for a DAA between 6/1/2019 and 06/01/2020. Data for this study were collected retrospectively using a report generated by the pharmacy electronic medical record and through manual chart review. Calculations for cost avoidance associated with prevention of DAA treatment failures are estimations based on the current average wholesale price (AWP) and wholesale acquisition cost (WAC) pricing. RESULTS: A total of 808 patients were identified as filling a prescription for HCV treatment during the measurement period. Average patient age was 49.8 years, and 60.5% of patients were male. A total of 267 patients (33%) were identified as having at least one drug-drug or drug-disease interaction. Of the 304 potential interactions identified, 132 drug interactions (43.9%) could have led to treatment failure and 172 (56%) could have resulted in adverse events. The estimated cost avoidance for interventions made by clinical pharmacists to avert treatment failures (132 regimens) was $387,968 and $323,306 using AWP and WAC pricing, respectively. CONCLUSION: Pharmacists in the specialty pharmacy setting are essential for the evaluation of potential drug and disease state interactions with HCV therapies. These interventions potentially averted treatment failures and adverse drug events.

Applicability of a new specialty pharmacy-reported measure describing completion of therapy for hepatitis C.

BACKGROUND: In 2019, the Utilization Review Accreditation Commission (URAC) required a new reporting measure for specialty pharmacies related to completion of therapy for hepatitis C virus (HCV). OBJECTIVE: To calculate HCV completion of therapy according to URAC criteria and compare it with a calculation with additional pharmacy proposed adjustments to assess its applicability. METHODS: This was an observational study of patients who received HCV treatment with a direct-acting antiviral (DAA) from 1 specialty pharmacy. All patients with prescription claims at a pharmacy who had a first fill for a DAA medication between the 2 measurement periods of January 1, 2018-December 31, 2018, and January 1, 2019-December 31, 2019, were included. Additional information was collected via a retrospective chart review and from the pharmacy's electronic medication system. The cumulative gap according to URAC was calculated from claims data by summing the number of days between the last days supply of 1 claim for the prescribed DAA and the subsequent claims. The pharmacy-proposed cumulative gap was calculated using additional information from patient chart notes in order to account for a true start date. RESULTS: A total of 1,485 patients were identified as having a first fill of a DAA between the 2 measurement periods. The HCV completion of therapy measure calculated per the URAC definition was 83.4% in 2018 and 86.5% in 2019. The only variable significantly associated with a > 15-day gap according to the URAC definition was if the first DAA order was delivered to the prescriber's office instead of the patient's home for 2018 (χ2 [1, N = 573] = 16.8, P < 0.001) and 2019 (χ2 [1, N = 836] = 12.6, P < 0.001). Using the pharmacy-proposed adjustment, the modified HCV completion rates for 2018 and 2019 were 88.9% and 89.9%, respectively. CONCLUSIONS: The accrediting body's definition of completion of therapy may report a falsely high rate of gaps in HCV therapy due to not accounting for the actual DAA start date. This information may prove beneficial for the accrediting body, as it reviews its initial definition of the HCV completion of therapy measure. DISCLOSURES: No outside funding supported this study. Levesque reports participation in AbbVie's speaker's bureau with regard to its immunology portfolio. The other authors have no possible financial or personal relationships with commercial entities to disclose that may have a direct or indirect interest in the matter of this study.