Anti-Granulocyte-Macrophage Colony-Stimulating Factor Monoclonal Antibody Gimsilumab for COVID-19 Pneumonia: A Randomized, Double-Blind, Placebo-controlled Trial.

Rationale: GM-CSF (granulocyte-macrophage colony-stimulating factor) has emerged as a promising target against the hyperactive host immune response associated with coronavirus disease (COVID-19). Objectives: We sought to investigate the efficacy and safety of gimsilumab, an anti-GM-CSF monoclonal antibody, for the treatment of hospitalized patients with elevated inflammatory markers and hypoxemia secondary to COVID-19. Methods: We conducted a 24-week randomized, double-blind, placebo-controlled trial, BREATHE (Better Respiratory Education and Treatment Help Empower), at 21 locations in the United States. Patients were randomized 1:1 to receive two doses of intravenous gimsilumab or placebo 1 week apart. The primary endpoint was all-cause mortality rate at Day 43. Key secondary outcomes were ventilator-free survival rate, ventilator-free days, and time to hospital discharge. Enrollment was halted early for futility based on an interim analysis. Measurements and Main Results: Of the planned 270 patients, 225 were randomized and dosed; 44.9% of patients were Hispanic or Latino. The gimsilumab and placebo groups experienced an all-cause mortality rate at Day 43 of 28.3% and 23.2%, respectively (adjusted difference = 5% vs. placebo; 95% confidence interval [-6 to 17]; P = 0.377). Overall mortality rates at 24 weeks were similar across the treatment arms. The key secondary endpoints demonstrated no significant differences between groups. Despite the high background use of corticosteroids and anticoagulants, adverse events were generally balanced between treatment groups. Conclusions: Gimsilumab did not improve mortality or other key clinical outcomes in patients with COVID-19 pneumonia and evidence of systemic inflammation. The utility of anti-GM-CSF therapy for COVID-19 remains unclear. Clinical trial registered with www.clinicaltrials.gov (NCT04351243).

American Heart Association (AHA) Scientific Sessions-2021 Annual Meeting

The AHA Scientific Sessions, the annual meeting of the Amer-ican Heart Association, highlights the latest cutting-edge basic, translational and clinical research in cardiovascular diseases. This year, the conference took place virtually due to the COVID-19 pandemic and comprised several days of live sessions and on-demand virtual content, including posters and prerecorded presentations.

Anti-gm-csf monoclonal antibody gimsilumab improved ventilator-free survival, decreased hospitalization length, and prevented nt-probnp rise in invasively ventilated patients with hyperinflammatory covid19 pneumonia: A subgroup analysis from the breathe trial suggests neurohormonal role for gm-csf inhibition

Background: Granulocyte-macrophage colony-stimulating factor (GM-CSF), a myeloid cell growth factor and pro-inflammatory cytokine, may drive the overactive host immune response in COVID-19. We conducted a clinical trial assessing the anti-GM-CSF monoclonal antibody gimsilumab for hyperinflammatory COVID-19 pneumonia (BREATHE). Here, we report a pre-specified subgroup analysis demonstrating a signal of benefit in patients invasively ventilated at baseline. Methods: BREATHE (NCT04351243) was a double-blind, randomized, placebo-controlled trial at 21 US locations. Patients were randomized 1:1 to receive two doses of IV gimsilumab or placebo one week apart. The study included hospitalized COVID-19 patients with hyperinflammation (CRP ≥50 mg/L or ferritin ≥1,000 ng/mL) and pre-ARDS lung injury or ARDS. The primary endpoint was all cause mortality at day 43, and key secondary outcomes assessed ventilator use and hospitalization length. Results: 225 patients were randomized and dosed. 41 patients were invasively ventilated at baseline. Steroid use and baseline characteristics were generally balanced across study arms in this subgroup. Ventilated patients treated with gimsilumab demonstrated improvements over placebo on the primary and key secondary endpoints (Table 1). Contrasting the placebo group, gimsilumabtreated patients did not experience a sharp rise in NT-proBNP, a marker of heart failure, through day 43 (Figure 1). Conclusions: GM-CSF inhibition may be therapeutic in ventilated COVID-19 patients through a neurohormonal mechanism. More studies are needed to assess the role of GM-CSF in COVID-19-associated cardiomyopathy, volume status, and ARDS.