LANADELUMAB REDUCES HAE ATTACK RATE: INTERIM FINDINGS FROM THE HELP OPEN-LABEL EXTENSION STUDY

Abstract

Introduction Efficacy of lanadelumab in preventing hereditary angioedema (HAE) attacks was demonstrated in the double-blind, phase 3 HELP study (NCT02586805). This analysis reports interim data (26May2017-1September2017) on HAE attack rate with lanadelumab in the ongoing open-label extension (OLE) study (NCT02741596). Methods Patients ≥12 years old with HAE type I/II who completed the double-blind study (rollovers), as well as eligible patients who had not previously participated (nonrollovers) were enrolled. Patients received a single 300mg lanadelumab dose at rollover and then received 300mg q2wks starting at the time of their first attack. Nonrollover patients received lanadelumab 300mg q2wks from Day 0. The number of investigator-confirmed HAE attacks during the treatment period was expressed as a monthly HAE attack rate (attacks/4 weeks). Results A total of 212 patients were treated (rollover, n=109; nonrollover, n=103); 92.9% remain enrolled. In the overall population (rollover and nonrollover), median age was 42.8 years. Most had HAE type 1 (89.2%); 50% had previously received C1-INH only. At baseline, patients had a median of 2.0 (mean [SD] 3.05 [2.66]) attacks/month. During the treatment period, median and mean (SD) attack rates were 0.0 and 0.30 (0.628), reflecting a median and mean (SD) reduction of 100% and 85.3% (68.4) from baseline in monthly HAE attack rate. On average, subjects were attack-free on most days during the treatment period (median 100%; mean [SD], 97.4% [6.08]), for a median duration of 105.0 days (mean [SD] 125.7 [81.5] days). Conclusions Lanadelumab remained highly effective in reducing HAE attacks in the HELP OLE study.