Real-world changes in costs over time among patients in the United States with hereditary angioedema on long-term prophylaxis with lanadelumab

Aims Investigate trends in paid lanadelumab costs over time in a population of patients persistent for 18 months, and to understand overall hereditary angioedema (HAE) treatment cost trends, including costs of acute medication/short-term prophylaxis and supportive care. Lastly, we sought to describe the proportion of lanadelumab patients with evidence of down titration via changes in total paid amounts for lanadelumab in a fixed time period. Methods Patients were identified in the Merative MarketScan Databases who had & GE;1 claim for lanadelumab during 1/1/2018-6/30/2022 (index), a & LE; 60-d gap in days of supply over 18 months, and were enrolled for & GE;6 months pre-index and 18 months post-index. Lanadelumab and HAE-specific costs were assessed during follow-up months 0-6, 7-12, and 13-18. Down titration was defined as a & GE; 25% decrease in lanadelumab costs from months 0-6 to months 7-12 or 13-18. Outcomes were compared between time periods using paired t-tests and McNemar's test. Results Fifty-four lanadelumab users were included; 25 (46%) had evidence of down titration. Lanadelumab costs decreased from $316,724 to $269,861 to $246,919 in months 0-6, 7-12, and 13-18, respectively (p < .01); total HAE treatment costs decreased from $377,076 to $329,855 to $286,074 in months 0-6, 7-12, and 13-18, respectively (p < .01). Limitations Persistence was determined via days of supply on medication claims; use of the medication was not confirmed. Down titration was based on costs; the lanadelumab regimen could not be assessed. Results may not be generalizable to uninsured patients or those without commercial or Medicare insurance. Conclusions Patients on long-term prophylaxis with lanadelumab experienced a significant reduction (24%) in HAE treatment costs over 18 months, driven by lower costs of acute medications and lanadelumab down titration. Down titration among appropriate patients with controlled HAE may lead to substantial savings in healthcare costs.