Proof of concept data were announced from an interim analysis of a phase 2 trial evaluating the efficacy and safety of LY-CoV555 for the treatment of symptomatic mild to moderate coronavirus disease 2019 (COVID-19) in the outpatient setting.

LY-CoV555 is a potent neutralizing IgG1 monoclonal antibody directed against the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The investigational therapy is expected to block viral attachment and entry into human cells.

The ongoing randomized, double-blind, placebo-controlled BLAZE-1 trial is assessing the treatment in adult patients with mild to moderate COVID-19 symptoms who are not currently hospitalized. Patients were randomized to receive LY-CoV555 700mg, 2800mg, 7000mg, or placebo intravenously. The prespecified primary end point was the change from baseline to day 11 in SARS-CoV-2 viral load; additional end points included the proportion of patients who experienced COVID-19 hospitalization, ER visit or death from baseline to day 29.

Interim results showed that the primary end point was met only with the 2800mg dose; near complete viral clearance by day 11 was observed in most patients, including those who received placebo. LY-CoV555 was associated with improvement in viral clearance as early as day 3. Additionally, the proportion of patients with persistently high viral load was reduced with LY-CoV555 at later time points.

Pooled across all dose groups, 1.7% (n=5/302) of patients treated with LY-CoV555 had a COVID-19-related hospitalization or ER visit compared with 6% (n=9/150) for placebo. Most hospitalizations occurred in patients with underlying risk factors (age or BMI), which according to investigators may suggest a greater positive effect of LY-CoV555 in higher-risk patients. No patients progressed to mechanical ventilation or death.

As for safety, LY-CoV555 was well tolerated with similar treatment emergent adverse events across all dose groups that were comparable to placebo. There were no drug-related serious adverse events reported. Additionally, the rate of resistance variants was found to be numerically higher in all dose groups (8%) compared with placebo (6%). 

Full data from the interim analysis will be published in a peer-reviewed journal. The trial is also investigating LY-CoV555 in combination with a second antibody, LY-CoV016, which binds to a different epitope in the SARS-CoV-2 spike region.

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“These interim data from the BLAZE-1 trial suggest that LY-CoV555, an antibody specifically directed against SARS-CoV-2, has a direct antiviral effect and may reduce COVID-related hospitalizations,” said Daniel Skovronsky, MD, PhD, Lilly’s chief scientific officer and president of Lilly Research Laboratories. “The results reinforce our conviction that neutralizing antibodies can help in the fight against COVID-19.”

The Company is also assessing the effects of LY-CoV555 in hospitalized patients with COVID-19 (phase 1 study) and in residents and staff at long-term care facilities (phase 3 study).

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Lilly announces proof of concept data for neutralizing antibody LY-CoV555 in the COVID-19 outpatient setting. Accessed September 16, 2020.