Lanadelumab Markedly Reduces Hereditary Angioedema Attacks Over 30-Month Period

Lanadelumab was effective for reducing hereditary angioedema (HAE) attacks at up to 30 months of treatment, suggesting the monoclonal antibody is associated with sustained long-term efficacy when used as HAE prophylaxis, according to study results presented at the American College of Allergy, Asthma & Immunology (ACAAI) Annual Scientific Meeting , held virtually from November 13 to 15.

The study was an open-label extension that included 109 patients aged 12 years or older with HAE type 1/2 who completed the HELP trial (ClinicalTrials.gov Identifier: NCT02586805). Patients received a single 300 mg dose of lanadelumab until first attack and subsequently received 300 mg every 2 weeks thereafter. Another group of 103 patients with HAE who did not participate in the HELP study were also enrolled and received 300 mg lanadelumab every 2 weeks from baseline.

Approximately 92.5% of the study population completed 12 or more months of treatment, whereas 81.6% completed 30 or more months (median, 33.0 months). Treatment with lanadelumab was associated with a marked reduction in the mean attack rate compared with baseline in the overall population (3.05 vs 0.25; reduction relative to baseline, 87.4%). The majority of patients (96.6%) experienced at least a 50% reduction in HAE attacks during treatment.

Treatment emergent adverse events (TEAEs) excluding HAE attacks were reported in 97.2% of patients. The most frequently reported TEAE was mild to moderate injection site pain (47.2%). More than half (54.7%) of patients reported treatment-related TEAEs, the most common of which were injection site pain (42.5%) and injection site erythema (16.0%). The majority of injection site reactions resolved within a 1-hour period (70.2%) or a day (92.6%) from onset.

A total of 6 (2.8%) patients discontinued therapy because of a TEAE, including 1 patient because of a treatment-related event (edema, joint pain, and wheals). There were no reported treatment-related serious TEAEs or deaths. In 7 (3.3%) patients, the investigators observed 11 treatment-related TEAEs of special interest. There were anti-lanadelumab antibodies present in 21 (9.9%) patients, with 6 (2.8%) positive for neutralizing antibodies. However, the neutralizing antibodies had “no apparent clinical impact,” according to the investigators.

Reference

Banerji A, Hao J, Yu M, Bernstein J, Johnston D, Riedl M. Long-term efficacy and safety of lanadelumab: final results from the HELP open-label extension study. Presented at: the American College of Allergy, Asthma & Immunology (ACAAI) Annual Scientific Meeting (Virtual Experience); November 13-15, 2020. Abstract P150.