Discontinuation Rates Matter When Evaluating Biologics in RA, Analysis Finds

Typically, models that evaluate the cost-effectiveness of using biologics to treat rheumatoid arthritis (RA) make certain assumptions about therapies given in sequence—namely, that if patients switch from one antitumor necrosis factor (TNF) inhibitor to another as therapies fail, the patients will progress through the full sequence.

But in the real world, that’s not always what happens. A modeling study presented at the 2020 International Society for Pharmacoeconomics and Outcomes Research virtual conference looked at the short-term consequences of stopping a therapy, which can happen if patients swap out one anti-TNF inhibitor for another.

Using the Truven Health MarketScan Research database, the researchers examined records from 10,442 patients with RA, covering a period from 2008 to 2016. This included 2732 patients who were taking adalimumab (Humira) and 2073 who were taking abatacept (Orencia), an immunomodulator. Those taking adalimumab had been taking the anti-TNF inhibitor for a median of 418 days, and 15.2% stopped biologic treatment afterward. Those taking abatacept had been taking the drug for a median of 582 days, and 13.8% stopped taking it afterward.

Over 2 years, swapping had a higher discounted cost ($66,260 vs $65,596), while the QALY (quality-adjusted life years), a measure of disease burden, was 0.92 vs 0.91, with 1 being a year in perfect health. The incremental cost-effectiveness ratio (ICER) was $74,185/QALY gained. According to the study authors, those costs are lower that the full sequence model ($74,460 and $73,838) for a similar QALY benefit, for which the ICER was $96,030/QALY. The effect of swapping on the ICER increased over a 5-year period

ICERs must be updated to reflect the fact that some patients discontinue biologics and swap in other products, the authors concluded. The impact on the ICER, they wrote, “has repercussions for decision makers and coverage coverage policy,” especially as the prospect of biosimilars loom in the class.

Reference

Karpes MA, Rasu R, Lal L, et al. Discontinuation plays a role when evaluating the cost effectivessness of the second biological drug for patients with rheumatoid arthritis. Presented a: Virtual ISPOR 2020, May 16-18, 2020. ispor.org/heor-resources/presentations-database/presentation/intl2020-3182/102681