Patients Taking Haegarda Used Less On-Demand Therapy, Reduce Plan Spending

A poster presented at the AMCP 2018 Annual Meeting showed that patients with hereditary angioedema who received Haegarda (C1 esterase inhibitor subcutaneous; CSL Behring) took less on-demand therapy during prophylactic treatment.

“Hereditary angioedema is characterized by recurrent, debilitating attacks of edema of the face, trunk, limbs, abdomen, and genitourinary and respiratory tracts, which generally require immediate treatment with acute medications on-demand therapy,” Shanthy Krishnarajah, MPH. Bsc, senior director of global health economics and reimbursement strategy at CSL Behring, and colleagues wrote. “In June 2017, the FDA approved [Haegarda] as routine prophylaxis to prevent attacks in adolescent and adult patients with HAE, based on the phase 3 COMPACT clinical trial.”

To examine how use of Haegarda impacted use of on-demand therapy before and during the use of prophylactic treatment, the researchers used patients from the COMPACT trial to compare data from 12 weeks before initiation of the study period, with results from after initiation. Within the COMPACT study, 90 patients completed the pre-randomization process of 4 weeks and a run-in period of up to 8 weeks, and 79 patients completed the trial, with on-demand therapy utilization data available for 43 patients.

Study results showed that the median number of uses of on-demand therapy decreased from three in the pre-randomization period to one in the post-initiation period. Further, in the pre-randomization period, five out of the study patients did not use any on demand therapy, compared with 21 in the prophylaxis with Haegarda period. 

“Patients with hereditary angioedema used less on-demand therapy during prophylactic treatment with C1-INH (SC) than during the pre-randomization period,” the researchers wrote. “The reduction in use of on-demand therapy for hereditary angioedema attacks will have cost implications.”

A second poster by Dr Krishnarajah and colleagues examined the budget impact of introducing Haegarda on the market compared with current offerings for hereditary angioedema.

The budget impact model found that switching 40% of hereditary angioedema in a 1 million member health plan, would avoid 37 attacks, save an average of $354,079 in overall health costs, and reduce treated per member per month spending by $1553.

“In each of the efficacy scenarios and sensitivity analyses, [Haegarda] reduced total annual costs associated with hereditary angioedema treatment,” the researchers concluded. “The magnitude of reduction is dependent on the market share gained and size of the treated population (assumed to be 25% of diagnosed HAE patients). Cost savings increased with greater number of hereditary angioedema attacks avoided.”

—David Costill