Remdesivir, the only antiviral drug authorized to treat COVID-19 could become far more accessible soon. On Monday, Gilead Sciences (GILD -1.74%) finished submitting a new drug application (NDA) to the FDA that could lead to full approval of the broad-spectrum antiviral, to be marketed as a treatment for COVID-19 under the brand name Veklury.

At the moment, Veklury is available under an emergency use authorization (EUA) that will lapse once the circumstances that justify it no longer exist. In addition to providing the company with some clarity about Veklury's future, a normal FDA approval will allow the company to actually market the drug and gain more control over its distribution.

Blood sample labeled COVID-19 positive.

Image source: Getty Images.

Under its EUA, Veklury can only be administered to patients with severe COVID-19, but it's unlikely that full approval will significantly boost sales into the larger population of patients with milder cases. Veklury needs to be administered through an intravenous infusion over a five-day treatment regimen.

The NDA is supported by two single-arm phase 3 trials that have told us very little. If the FDA hits a sticking point over Veklury, it will be the lack of a mortality benefit observed during the only randomized, placebo-controlled study supporting the application, a phase 3 trial conducted by the National Institute of Allergy and Infectious Diseases (NIAID).

During the NIAID study, a majority of hospitalized patients treated with Veklury recovered after 11 days compared to 15 days among those who received the placebo. Shortening the recovery time isn't an insignificant benefit, but given that it does not produce any measurable reduction in mortality, Veklury doesn't set a high bar for incoming antiviral treatments to clear.

NIAID is currently treating patients with LY-CoV555 from Eli Lilly (LLY 0.73%) in a multi-agent head-to-head study that seeks to discover which among several experimental COVID-19 treatments performs that best.