ARCA biopharma's Tissue Factor Inhibitor Disappoints In Mid-Stage COVID-19 Study

ARCA biopharma Inc ABIO announced results from the ASPEN-COVID-19 Phase 2 trial evaluating rNAPc2, a specific inhibitor of tissue factor, as a potential treatment for patients hospitalized with COVID-19.

• In the 160-patient trial, both doses of rNAPc2 demonstrated a treatment benefit; however, neither dose achieved statistical significance for the primary efficacy endpoint of change in D-dimer level from Baseline to Day 8 compared to standard of care heparin.
• The pooled lower and higher rNAPc2 dose groups demonstrated a reduction in D-dimer levels of 16.8% versus 11.2% for the standard of care heparin.
• The treatment effects of rNAPc2 and heparin were different in mild versus severe categories, with generally decreasing D-dimer levels from baseline in mild patients.
• But in severe patients, D-dimer levels were increasing in the Heparin group with no change in the rNAPc2 groups.
• On the secondary endpoint related to eligibility for hospital discharge, the rNAPc2 combined arms log-rank hazard ratio was 0.88 compared to heparin, representing a one-day reduction in time-to-recovery.
• The thrombosis events component of the composite clinical outcome endpoint yielded nine events in the heparin group versus six in the combined rNAPc2 groups; neither results were statistically significant.
• rNAPc2 was well-tolerated at both doses. There were no serious treatment-related adverse events, and no dose-dependent increase in adverse events was observed.
• Price Action: ABIO shares are down 24.4% at $1.74 during the premarket session on the last check Friday.