ADARx Pharmaceuticals has dosed the first participant in its Phase III trial of ADX-324 for the prophylactic treatment of hereditary angioedema (HAE).
ADX-324, an investigational short-interfering RNA (siRNA) therapy, also received orphan drug designation from the US Food and Drug Administration (FDA) for HAE.
The Phase III placebo-controlled, randomised, double-blind STOP-HAE trial is designed to assess the therapy’s efficacy in preventing attacks in adults with Type I and Type II HAE.
It will also evaluate health-related quality of life (HRQoL), pharmacodynamics (PD), pharmacokinetics (PK), and safety.
Nearly 90 participants will be administered either ADX-324 300mg every six months, 240mg every three months, or a placebo.
Subjects who conclude the study will qualify to participate in a long-term open-label extension trial.
ADARx president and CEO Zhen Li said: “Despite advances in prophylactic therapy, most HAE patients remain at risk of breakthrough attacks and do not achieve sustained, long-term attack-free control.
“In addition, the currently approved prophylaxis treatments require monthly or more frequent injections. We believe the FDA’s orphan drug designation for ADX-324 underscores the continued need for additional treatment options and highlights the potential of ADX-324 to provide extended attack-free periods with substantially reduced dosing frequency.”
HAE is a rare, genetic disorder marked by unpredictable swelling attacks caused by dysregulation of the kallikrein-kinin system that regulates inflammation, blood pressure, coagulation and pain.
The enrolment follows encouraging Phase I/II results indicating that the therapy achieved durable suppression of prekallikrein protein levels with a favourable safety profile.
In May 2023, ADARx dosed the first cohort in a Phase I trial of ADX-324 to treat HAE.
