Takhzyro, a monoclonal antibody, was found to safely reduce monthly attack rates in adolescents with hereditary angioedema, according to research presented at the American Academy of Allergy, Asthma and Immunology annual meeting.
The FDA approved Takhzyro (lanadelumab, Dyax Corp.) in August 2018 for treating hereditary angioedema (HAE), a rare, potentially life-threatening disorder caused by a deficiency of the C1 inhibitor protein, in patients aged 12 years and older.
Paula J. Busse, MD, FAAAAI, associate professor of medicine and clinical immunology at the Icahn School of Medicine at Mount Sinai, and colleagues conducted a phase 3 trial and then an open-label extension study of the efficacy and safety of lanadelumab in adolescents with HAE with C1-inhibitor deficiency.
The phase 3, multicenter, double-blind trial included patients aged 12 years and older with at least one investigator-confirmed attack over the past 4 weeks. Participants were assigned to placebo or lanadelumab 150 mg every 4 weeks, 200 mg every 4 weeks or 200 mg every 2 weeks.
In the open-label extension study — which lasted from May 2016 to September 2017 — rollover patients from the phase 3 study and other patients received 300 mg of lanadelumab once every 2 weeks. The researchers recorded the monthly attack rate (MAR) and other treatment-emergent adverse events (TEAEs).
Ten of 125 patients in the phase 3 trial were adolescents. Four adolescents treated with placebo had a mean MAR of 1.825 during a run-in period and 0.917 during the treatment period. One patient with 150 mg of lanadelumab every 4 weeks had a mean MAR of 1.000 during run-in and 0.000 during treatment. Three patients with 300 mg every 4 weeks treatment arm had a mean MAR of 0.989 during run-in and 0.304 during treatment. Two patients in the 300 mg every 2 weeks treatment arm had a mean MAR of 1.948 during the run-in and 0.306 during treatment. The researchers reported that three patients had nonserious lanadelumab-related TEAEs.
Twenty-one patients (9.9%) in the extension study were adolescents. Eight rollover patients had a mean MAR of 1.75, and 13 other patients had a mean MAR of 1.54 at baseline, and 0.35 and 0.77, respectively during treatment. This resulted in a mean percent change of –84.37 and –94.89, respectively. Busse and colleagues wrote that nine patients had nonserious lanadelumab-related TEAEs
“Children with hereditary angioedema live in fear of spontaneous, painfully debilitating, and sometimes life-threatening attacks of angioedema, which typically last for several days,” Martha White, MD, the director of research for the Institute for Asthma & Allergy, who was not involved in the study, told Infectious Diseases in Children. “A prophylactic therapy such as lanadelumab, which can be administered every 2 to 4 weeks, offers hope and peace of mind for HAE adolescent patients and their families.” – by Bruce Thiel
Busse PJ, et al. Efficacy and safety of lanadelumab for prophylactic treatment in adolescents with hereditary angioedema (HAE) Presented at: American Academy of Allergy, Asthma and Immunology Annual Scientific Meeting; Feb. 22-25, 2019; San Francisco.
Disclosure: White reports no relevant financial disclosures. Infectious Diseases in Children was unable to determine relevant financial disclosures for Busse at time of publication.