Over a 10-year period, apomorphine sublingual film was projected to be dominant in 70% of patients compared with apomorphine hydrochloride injection and 71% vs levodopa inhalation powder.
Using a cost-effectiveness model, recently conducted research showed that apomorphine sublingual film (Kynmobi; Sunovion), an FDA-approved medication to treat OFF episodes in patients with Parkinson disease (PD), is less costly and more effective on average compared with apomorphine hydrochloride (Apokyn; Supernus Pharmaceuticals) and levodopa inhalation powder (Inbrija; Acorda Therapeutics).
After receiving US approval in 2020, investigators set out to understand how apomorphine sublingual film compared to other on-demand treatments from a US payer perspective over a 10-year period. Lead author Andrew Thach, PhD, MS, director, Health Economics and Outcomes Research, Sunovion Pharmaceuticals, and colleagues summarized and compared total and incremental patient costs (in 2020 US dollars), total time spent without OFF episode symptoms, and quality-adjusted life years (QALY) gained.
Best case analysis used an annual discount rate of 3% for costs and utilities. Over a 10-year time horizon, on-demand treatment costs were estimated at $42,095 for apomorphine sublingual film, $276,320 for apomorphine hydrochloride, and $69,577 for levodopa inhalation powder. This resulted in treatment cost differences of $234,225 between the sublingual film vs apomorphine hydrochloride, and $27,482 between apomorphine sublingual film and the inhalation powder.
Over the same time period, apomorphine sublingual film was also associated with the highest utility, with incremental QALYs of 0.019 compared with apomorphine hydrochloride (4.107 vs 4.088 QALYs, respectively) and 0.235 compared with levodopa inhalation powder (4.107 vs 3.872 QALYs). Patients on levodopa inhalation powder recorded 10,076 total hours of OFF time, the most of all the arms, compared with 7732 and 7314 hours for apomorphine sublingual film and apomorphine hydrochloride, respectively. Notably, all 3 treatments were associated with 6.02 life-years.
Because of the higher discontinuation rates, patients in the apomorphine sublingual film group incurred slightly higher medical costs compared with apomorphine hydrochloride ($3403 vs $3363; difference, $40), while the substantially higher efficacy of apomorphine sublingual film resulted in lower incurred medical costs compared to the levodopa inhalation powder group ($3403 vs $3627; difference, $224). Furthermore, there was a range in costs related to treatment-emergent adverse events, which totaled $367 for apomorphine sublingual film, $530 for apomorphine hydrochloride, and $114 for levodopa inhalation powder.
Patients treated with apomorphine sublingual film saved an estimated $559 for every OFF hour avoided compared to those on apomorphine hydrochloride. Additionally, apomorphine sublingual film was “dominant” over levodopa inhalation powder in terms of incremental cost per OFF hour, and “dominant” over both apomorphine hydrochloride and levodopa inhalation powder in terms of incremental cost per QALY gained. The microsimulation findings indicated that apomorphine sublingual film was dominant across approximately 70% of runs against either comparator, with various analyses showing little effect on the comparative findings.
Thach et al also conducted 4 scenario analyses that were compared with the base case. They included (1) using efficacy inputs from a different indirect comparison of apomorphine sublingual film and levodopa inhalation powder, (2) assuming linear change in utility per OFF hour reduced, (3) limiting the model horizon to 5 years, and (4) considering costs owing to caregiver burden.
In all of these scenarios, apomorphine sublingual film continued to show dominance over levodopa inhalation powder. In scenario 4, which considered informal caregiver time (hours spent caregiving) and associated costs, the incremental costs of apomorphine sublingual film vs apomorphine hydrochloride were $231,110 and those of apomorphine sublingual film vs levodopa inhalation powder were $45,719. The incremental QALYs gained from apomorphine sublingual film vs apomorphine hydrochloride and apomorphine sublingual film vs levodopa inhalation powder were 0.019 and 0.235, respectively.
"The progression of PD differs in each patient, thus the cost-effectiveness of certain treatments and how they impact HRQOL or meet individual patients’ needs should be considered, with the goal of maximizing the time spent in less severe disease states," Thach et al wrote. "In addition, studies that consider other indirect costs, such as patients’ work loss or impacts on income, may be considered as avenues for future research."