Lenzilumab Efficacy and Safety in Newly Hospitalized COVID-19 Subjects: Results from a Phase 3 Randomized Double-Blind Placebo-Controlled Trial

Background. Severe coronavirus disease 2019 (COVID-19) often results from the immune-mediated cytokine storm, triggered by granulocyte macrophage-colony stimulating factor (GM-CSF), potentially leading to respiratory failure and death. Lenzilumab, a novel anti-human GM-CSF monoclonal antibody, neutralizes GM-CSF and demonstrated potential to improve clinical outcomes in a matched case-cohort study of patients with severe COVID-19 pneumonia. This Phase 3 randomized, double-blind, placebo-controlled trial investigated the efficacy and safety of lenzilumab to improve the likelihood of survival without invasive mechanical ventilation (SWOV), beyond available treatments. Methods. Hypoxic patients, hospitalized with COVID-19 (n=520), requiring supplemental oxygen, but not invasive mechanical ventilation, were randomized on Day 0 to receive lenzilumab (1800mg, n=261) or placebo (n=259), and available treatments, including remdesivir and/or corticosteroids;and were followed through Day 28. Results. Baseline demographics were comparable between groups: male, 64.7%;mean age, 60.5 years;median CRP, 79.0 mg/L. Patients across both groups received steroids (93.7%), remdesivir (72.4%), or both (69.1%). Lenzilumab improved the primary endpoint, likelihood of SWOV in the mITT population, by 1.54-fold (HR: 1.54;95%CI: 1.02-2.32, p=0.0403). Lenzilumab improved SWOV by 1.91-fold (nominal p=0.0073) and 1.92-fold (nominal p=0.0067) in patients receiving remdesivir or remdesivir and corticosteroids, respectively. A key secondary endpoint of incidence of IMV, ECMO or death was also improved in patients receiving remdesivir (p=0.020) or remdesivir and corticosteroids (p=0.0180). Treatment-emergent serious adverse events were similar across both groups. Conclusion. Lenzilumab significantly improved SWOV in hypoxic COVID-19 patients upon hospitalization, with the greatest benefit observed in patients receiving treatment with remdesivir and corticosteroids. NCT04351152.

C-reactive protein as a biomarker for improved efficacy of lenzilumab in Covid-19 patients: results from the LIVE-AIR trial

BackgroundThe hyperinflammatory cytokine storm (CS) of COVID-19 is mediated by GM-CSF leading to release of downstream inflammatory chemokines, cytokines, and markers of systemic inflammation (C-reactive protein, CRP). The LIVE-AIR study demonstrated that lenzilumab, an anti-GM-CSF monoclonal antibody in patients hospitalized with COVID-19, safely improved the likelihood of achieving the primary endpoint, survival without ventilation (SWOV) by 1.54-fold (HR: 1.54;95%CI: 1.02–2.32, p=0.0403) compared with placebo. An exploratory analysis in patients with CRP<150 mg/L and age<85 years was conducted to determine lenzilumab efficacy when administered prior to advanced inflammation.MethodsLIVE-AIR was a phase 3 randomized, double-blind, placebo-controlled trial. Patients with COVID-19 (n=520), >18 years, and ≤94% oxygen saturation on room air and/or requiring supplemental oxygen, but not invasive mechanical ventilation (IMV), were randomized to receive lenzilumab (600 mg, n=261) or placebo (n=259) via three intravenous infusions administered 8 hours apart. Participants were followed through Day 28 following treatment.ResultsOverall, baseline demographics were comparable between treatment groups: male, 64.7%;mean age, 60.5 years;mean BMI, 32.5 kg/m2;median CRP, 79 mg/L;CRP was <150 mg/L in 78% of participants. Participants received steroids (93.7%), remdesivir (72.4%), or both (69.1%). Lenzilumab (n=159) improved the likelihood of SWOV by 3.04-fold in participants with CRP<150 mg/L and age<85 years (3.04;1.68–5.51, nominal p=0.0003) compared with placebo (n=178). Response to lenzilumab was observed in the first through third quartiles of baseline CRP (<41 mg/L, HR:8.33;41<79 mg/L, HR:1.60;79<137 mg/L, HR: 2.12;>137 mg/L, HR: 1.17). The incidence of IMV, ECMO, or death was reduced (OR: 0.31;95%CI: 0.15–0.63, p=0.002) and mortality was improved by 2.22-fold (OR: 2.22;95%CI: 1.07–4.67, p=0.034). In these participants, lenzilumab decreased CRP as early as Day 2 following treatment, compared with placebo which was further decreased by 38% on Day 28 compared with placebo (24.4±3.4 mg/L vs 39.1±4.9 mg/L).ConclusionLenzilumab significantly improved SWOV in hospitalized, hypoxic participants with COVID-19 pneumonia with the greatest benefits in SWOV and survival in patients with CRP<150 mg/L and age <85 years. Inhibition of GM-CSF, an orchestrator of CS, early in the hyperinflammatory response improved outcomes in COVID-19. NCT04351152