Phase III trial of sipavibart long-acting antibody preventing COVID-19 in immunocompromised patient population
Positive high-level results from the SUPERNOVA Phase III COVID-19 pre-exposure prophylaxis (prevention) trial showed AstraZeneca’s sipavibart (formerly AZD3152), an investigational long-acting antibody (LAAB), demonstrated a statistically significant reduction in the incidence of symptomatic COVID‑19 compared to control (tixagevimab/cilgavimab or placebo) in an immunocompromised patient population.
The trial met both dual primary endpoints; the first one being the relative risk reduction of symptomatic COVID-19 caused by any SARS-CoV-2 variant and the second being the relative risk reduction of infections caused by SARS-CoV-2 variants not containing the F456L mutation. SUPERNOVA demonstrated the potential benefit of sipavibart in an evolving variant landscape in which COVID-19 cases captured over the course of the trial were caused by several different SARS-CoV-2 variants.
SUPERNOVA is a large Phase III global trial providing the only efficacy data in immunocompromised patients, demonstrating the potential benefit of a COVID-19 antibody against recent SARS-CoV-2 variants.
Immunocompromised patients include those with blood cancer, organ transplant recipients, patients with end-stage renal disease requiring dialysis, patients receiving B-cell depleting therapy within the past year, and those taking immunosuppressive medications. Despite accounting for approximately 4% of the population, immunocompromised patients make up about 25% of COVID-19 hospitalisations, ICU admissions, and deaths, even after multiple doses of COVID-19 vaccines.1-6
Sipavibart was well tolerated in the trial and preliminary analyses show adverse events were balanced between the control and sipavibart arms.
The data will be presented at a forthcoming medical meeting. AstraZeneca is in dialogue with regulatory authorities on potential authorisation or approval pathways.
Sipavibart is an investigational long-acting monoclonal antibody (LAAB) against COVID-19 designed to provide broad and potent coverage across Omicron and ancestral viral variants by neutralising spike protein interaction with the host receptor ACE2.
Sipavibart was derived from B-cells donated by convalescent patients after SARS-CoV-2 infection. Sipavibart has been engineered using the same antibody scaffold as Evusheld and was optimised with the same half-life extension and reduced Fc effector function and complement C1q binding platform.7 The reduced Fc effector function aims to minimise the risk of antibody-dependent enhancement of disease - a phenomenon in which virus-specific antibodies promote, rather than inhibit, infection and/or disease.
Sipavibart was licensed by AstraZeneca in May 2022 from RQ Biotechnology.
Source: Press Release