Prescribing trends in direct-acting antivirals for the treatment of hepatitis C in Ontario, Canada

Background — Direct-acting antivirals (DAA) offer an opportunity to cure hepatitis C. Reimbursement for DAAs has changed on two occasions since their inclusion on the Ontario public formulary. Whether these changes have appreciably modified prescribing patterns and increased access to DAAs is unknown. 

Methods — We conducted a repeated cross-sectional study of DAA reimbursement by the Ontario Public Drug Programs from January 1, 2012, to December 31, 2018, to summarize the use of DAAs in Ontario and describe changes in DAA prescribing physician specialties over this period. We measured the total number of users quarterly. Results are reported overall and by prescriber type. 

Results — A total of 27,116 individuals received a publicly funded prescription for a DAA from the first quarter (Q1) of 2012 to the fourth quarter (Q4) of 2018. Nearly two-thirds (n = 17,813; 65.7%) of all DAAs were prescribed by gastroenterologists, hepatologists, or infectious disease specialists. Use of DAAs over time appears to have had three major phases in uptake: (1) the introduction of DAA treatments on the Ontario public drug formulary as a prior authorization benefit in Q1 2015, (2) expanded listing of all DAAs as limited-use products on the formulary in Q1 2017, and (3) the introduction of newer DAAs in Q2 2018. 

Conclusions — Changes in listing of these agents had a direct impact on the use of DAAs overall. Generally, broader listing expanded access but did not appear to shift utilization patterns to primary care prescribers. Further understanding of who is not receiving treatment is needed.