OBJECTIVES: Hereditary transthyretin-mediated (hATTR) amyloidosis is a rare, inherited, rapidly progressive, life-threatening disease caused by the deposition of TTR proteins in the nerves and other organs. The U.S. prevalence of hATTR amyloidosis with polyneuropathy is estimated to be 10,000-15,000 patients, although fewer than 3,000 have been diagnosed. In 2018, patisiran and inotersen were approved for the treatment of this condition. The objective of this analysis was to estimate the budget impact to a third-party payer of reimbursing patisiran for its approved indication under various scenarios.

METHODS: An economic model was developed in Microsoft Excel^® to estimate the budget impact of reimbursing patisiran in a hypothetical U.S. commercial health plan with 1 million covered lives over a 3-year time horizon. The model assessed the incremental per-member-per-month (PMPM) budget impact of covering patisiran by comparing: 1) treatment landscape with reimbursement of inotersen, without patisiran versus 2) treatment landscape with reimbursement of patisiran and inotersen. In both treatment landscapes, a proportion of patients received best supportive care (BSC) alone or in addition to either patisiran or inotersen. All costs for treatment acquisition and administration (including required pre-medications), monitoring, and serious adverse event costs were reported in 2018 U.S. dollars. Alternative scenarios were tested.

RESULTS: Patisiran reimbursement had an incremental budget impact of $0.008 PMPM over a 3-year period, or $284,449 in total incremental costs. Scenario analyses showed a similar budget impact from the Medicare Advantage perspective ($0.009 PMPM). Administration of patisiran as home infusion, rather than outpatient infusion, yielded a cost savings of $0.002 PMPM.

CONCLUSIONS: Reimbursement of patisiran for the treatment of the polyneuropathy of hATTR amyloidosis is expected to have a minimal budget impact to health plans from both commercial and Medicare Advantage perspectives. If patisiran is administered at home, cost savings may be anticipated.