Ionis Reports Positive Topline Phase 2 Data of Antisense Treatment for HAE
March 29, 2021
Rare Daily Staff
Ionis Pharmaceuticals said topline data from its phase 2 clinical study of IONIS-PKK-LRx met its primary and secondary endpoints, achieving significant reductions in the number of attacks suffered by patients with hereditary angioedema (HAE) compared to placebo.
The study demonstrated a mean reduction of 90 percent in the number of monthly HAE attacks in weeks one to 17 of the study and a mean reduction of 97 percent in the number of monthly HAE attacks in weeks five to 17. In weeks five to 17, 92 percent of patients treated with IONIS-PKK-LRx were attack-free compared to none in the placebo group.
Hereditary angioedema is a rare autosomal dominant disease that results in recurrent, painful attacks of swelling affecting the arms, legs, face, intestinal track and airway. Without preventive treatment, HAE attacks can be frequent and severe and, in some patients, life-threatening. Physicians have long prescribed prophylactic treatment approaches, including C1-INH replacement therapies and more recently inhibitors of plasma kallikrein, to prevent and reduce the severity of HAE attacks. Despite these available therapies, patients with HAE may experience breakthrough attacks.
IONIS-PKK-LRx is an investigational antisense medicine designed to reduce the production of prekallikrein, or PKK, which plays a key role in the activation of inflammatory mediators associated with acute attacks of HAE.
“These topline Phase 2 study results support a profile for IONIS-PKK-LRx as a potential best-in-class prophylactic treatment for patients with HAE, with excellent efficacy, safety and tolerability along with the convenience of once per month low volume subcutaneous injections,” said Kenneth Newman, Ionis’ vice president of clinical development and leader of the pulmonology and immunology franchise. “These results highlight the potential benefits and advantages of IONIS-PKK-LRx for the treatment of hereditary angioedema and more broadly underscore the power of Ionis’ antisense technology to target the root causes of rare diseases like HAE.”
In the Phase 2 clinical study, 20 adults with Type 1 or Type 2 HAE were randomized and received either IONIS-PKK-LRx or placebo subcutaneously once monthly for 17 weeks. The primary endpoint was the reduction of monthly HAE attacks compared to placebo.
Secondary endpoints included the reduction of monthly attacks in weeks five to 17, reduction in the number of moderate or severe attacks in weeks one to 17, the number of moderate or severe attacks in weeks five to 17 and the number of attacks requiring acute therapy in weeks five to 17.
The majority of adverse events during the study were mild with a frequency that was similar between groups. The most common treatment-emergent adverse events were headache and nausea, which were seen more frequently in the placebo arm compared to the active treatment arm. Ionis expects to present a full analysis of its phase 2 study of IONIS-PKK-LRx at a medical conference later this year.
Photo: Kenneth Newman, Ionis’ vice president of clinical development and leader of the pulmonology and immunology franchise
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