(102) Evaluation of Non-Adherence to Oral Anticancer Agents in a Medically-Integrated Specialty Pharmacy

Poster Abstract:

Background: Oral anticancer agents (OAAs) have transformed care for patients with various malignancies, in some instances extending survival and delaying progression. However, this benefit requires high medication rates.1 Medically-integrated dispensing (MID) specialty pharmacies have been shown to improve patient knowledge and adherence to OAAs.2-4 However, adherence barriers continue to persist even in MID pharmacies.

Objective: We looked at reasons for non-adherence amongst patients who were taking oral anticancer agents from MID pharmacies.

Methods: We used prescription fill data to determine whether a patient filled their drugs at our internal MID pharmacy. A repeated measures logistic regression model was used to determine which factors were associated with cancer drug adherence. A patient was on our repeated measure if they took multiple drugs at different times, although their drugs did not overlap. Adherence was defined was having ≥90% adherence Our covariates included the following, age, sex, race, ethnicity, Insurance, Elixhauser comorbidity group (A sum of how many comorbidity groups a patient had), cancer type (based on which clinic they were seen at), and a dichotomous variable for COVID was defined as having a first fill on or after March 1st, 2020. For patients who had ≥30 day gaps in fill, electronic medical records (EMR) were reviewed to identify documented causes of non-adherence.

Results: There were a total of 3252 eligible patients of whom 1015 had drug fill data. 23% (N=233) had a suboptimal PDC ( < 90%). Demographic and clinical factors that were predictive of suboptimal PDC included: a diagnosis of thoracic and breast cancers (P < 0.0001 and P=0.031 respectively); and Hispanic ethnicity (P=0.011). Although there were Black-White disparities, these disparities disappeared when controlling for confounding variables. Age, sex, insurance status, comorbidities, and treatment during the COVID pandemic were not predictors of suboptimal PDC. 156 patients had a ≥30 day gap in medication fill and detailed EMR review was completed. For patients who had a 30-day gap, common documented reasons for gaps included: clinician holding (N=81), toxicities (N=49), non-clinician holding (i.e. patient non-adherence) (N=31). Additional reasons included: cost-related (N=6), forgetfulness (N=7), delay in shipment by pharmacy (N=5), and insurance lapse (N=4). Of note, the documented reasons were not mutually exclusive.

Conclusion: Despite some success with the MID model, there are some gaps in medication non-adherence in patients taking OAAs. Prospective evaluation is needed to better understand the impact of clinician-directed dose holds and discontinuations to appropriately interpret PDC reporting in future studies.

References (must also be included in final poster): 1. Kong JH, Go T-H, Lee JY, et al. Adherence to tyrosine kinase inhibitor affects overall survival in adult korean chronic myeloid leukemia patients; based on the national health information database. Blood. 2018;132(Supplement 1):1745-1745. doi:10.1182/blood-2018-99-111645
2. Muluneh B, Schneider M, Faso A, et al. Improved Adherence Rates and Clinical Outcomes of an Integrated, Closed-Loop, Pharmacist-Led Oral Chemotherapy Management Program. J Oncol Pract. 2018;14(6):e324-e334. doi:10.1200/JOP.17.00039
3. Zerillo JA, Goldenberg BA, Kotecha RR, Tewari AK, Jacobson JO, Krzyzanowska MK. Interventions to improve oral chemotherapy safety and quality: A systematic review. JAMA Oncol. 2018;4(1):105-117. doi:10.1001/jamaoncol.2017.0625
4. Rosenberg SM, Petrie KJ, Stanton AL, Ngo L, Finnerty E, Partridge AH. Interventions to enhance adherence to oral antineoplastic agents: A scoping review. J Natl Cancer Inst. 2020;112(5):443-465. doi:10.1093/jnci/djz244
5. Cherrington A, Martin MY, Hayes M, et al. Intervention mapping as a guide for the development of a diabetes peer support intervention in rural Alabama. Prev Chronic Dis. 2012;9:E36. doi:10.5888/pcd9.110053