Lenzilumab Significantly Improves COVID-19 Survival Without Invasive Ventilation

In newly hospitalized hypoxic patients with COVID-19, the monoclonal antibody significantly improved survival without invasive mechanical ventilation compared with placebo and available treatments, according to phase 3 trial results.

For hypoxic patients hospitalized with COVID-19, lenzilumab significantly improved survival without invasive mechanical ventilation (SWOV) compared with placebo, according to phase 3 trial results presented virtually at IDWeek 2021.

Lenzilumab’s potential to improve clinical outcomes for patients with COVID-19 hinges on its ability to neutralize granulocyte macrophage-colony stimulating factor (GM-CSF), a key immune-mediated cytokine that is part of the “storm” of inflammatory response that occurs with COVID-19 infection. Investigators sought to test the novel monoclonal antibody’s efficacy and safety along with available treatments in this randomized, double-blind, placebo-controlled trial.

A total of 520 patients were included in the analysis. These individuals were hypoxic and required supplemental oxygen, but not invasive mechanical ventilation. Participants were randomized on Day 0 to receive either lenzilumab (1800 mg, n = 261) or placebo (n = 259), along with available treatments (such as remdesivir and/or corticosteroids). Investigators monitored outcomes and followed patients through 28 days, with a primary end point of SWOV and secondary end point of incidence of invasive mechanical ventilation (IMV), extracorporeal membrane oxygenation (ECMO), or death.

Between the study arms, baseline demographics were comparable: 64.7% male, median age 60.5 years, median C-reactive protein level of 79.0 mg/L. In addition to the study drug or placebo, many patients in both groups received steroids (93.7%), remdesivir (72.4%), or both (69.1%).

In the modified intent-to-treat population, administration of lenzilumab improved SWOV by 1.54-fold (HR: 1.54; 95%CI: 1.02-2.32, P = .0403), and by 1.91-fold (nominal P = .0073) and 1.92-fold (nominal P = .0067) among patients receiving remdesivir or remdesivir and corticosteroids, respectively.

In patients receiving remdesivir or remdesivir and corticosteroids, the secondary end point of incidence of IMV, ECMO, or death also improved (P = .020 and P = .0180, respectively). Both groups also experienced similar reports of treatment-emergent serious adverse events.

“Lenzilumab significantly improved SWOV in hypoxic COVID-19 patients upon hospitalization, with the greatest benefit observed in patients receiving treatment with remdesivir and corticosteroids,” investigators concluded.

The study, “Lenzilumab efficacy and safety in newly hospitalized COVID-19 subjects: results from a phase 3 randomized double-blind placebo-controlled trial,” was presented virtually at IDWeek 2021, held September 29-October 3, 2021.