title: Patient and plan characteristics affecting abandonment of oral oncolytic prescriptions.
abstract: OBJECTIVE
  To calculate the abandonment rate of oral oncolytic medications and identify factors that may affect likelihood of abandonment.
  
  
  METHODS
  Cross-sectional cohort study using administrative claims data.
  
  
  METHODS
  We analyzed a nationally representative pharmacy claims database and identified 10,508 patients with Medicare and commercial insurance for whom oral oncolytic therapy was initiated between 2007 and 2009. We calculated the abandonment rate for the initial claim, in which abandonment was defined as reversal of an adjudicated pharmacy claim without a subsequent paid claim for any oncolytic (oral or intravenous) within the ensuing 90 days. We assessed likelihood of abandonment using bivariate and multivariate logistic regression analyses including patient demographics, plan type, drug type, cost sharing, and concurrent prescription activity.
  
  
  RESULTS
  The abandonment rate of newly initiated oral oncolytics was 10.0%. Unadjusted bivariate analyses found that high cost sharing, increased prescription activity, lower income, and Medicare coverage were associated with a higher abandonment rate (P <.05). In the logistic regression model, claims with cost sharing greater than $500 were 4 times more likely to be abandoned than claims with cost sharing of $100 or less (odds ratio [OR], 4.46; P <.001). Patients with 5 or more prescription claims processed within in the previous month had 50% higher likelihood of abandonment than patients with no other prescription activity (OR, 1.50; P <.001).
  
  
  CONCLUSIONS
  Abandonment of newly prescribed oral oncolytic therapy is not uncommon, and the likelihood increases for patients enrolled in plans with pharmacy benefit designs that require high cost sharing. Increased concurrent prescription activity was also associated with a higher abandonment rate. These factors should be taken into account when considering likely adherence to cancer therapy.
authors.affiliation: Avalere Health, Health Economics and Outcomes Services, 1350 Connecticut Ave NW, Washington, DC 20036, USA.
authors.forename: Sonya Blesser
authors.initials: SB
authors.lastname: Streeter
authors.forename: Lee
authors.initials: L
authors.lastname: Schwartzberg
authors.forename: Nadia
authors.initials: N
authors.lastname: Husain
authors.forename: Michael
authors.initials: M
authors.lastname: Johnsrud
mesh_terms: D000284:Administration, Oral; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000191:economics; D015331:Cohort Studies; D017047:Cost Sharing; D003430:Cross-Sectional Studies; D006801:Humans; D019458:Insurance Coverage / Q000458:organization & administration*; D016013:Likelihood Functions; D009062:Mouth Neoplasms / Q000188:drug therapy*; D010349:Patient Compliance; D012044:Regression Analysis
chemical_list: D000970:Antineoplastic Agents