Regeneron Pharmaceuticals (REGN -0.09%) and Eli Lilly (LLY -1.81%) are both developing potential new coronavirus treatments that could become available long before any vaccine candidates have a chance to prove themselves safe and effective. In fact, at least one COVID-19 treatment candidate could become available in U.S. hospitals in time to make this Halloween a lot less frightening.

Medical conference activity

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Are these coronavirus treatment candidates worth the attention they're attracting right now? Here's what you should know about potential treatment options and the paths they're taking to reach patients that need them. 

Regeneron: REGN-COV2 

This combination of coronavirus-neutralizing antibodies was propelled into the spotlight after President Trump called it a cure for COVID-19 in a video recorded outside the Oval Office several days after he received it.

Regeneron developed REGN-COV2 to mimic a pair of proteins humans produce in response to SARS-CoV-2, the virus responsible for the COVID-19 pandemic. Observations taken during a recent interim assessment of a pivotal study showed REGN-COV2 reduced viral load for COVID-19-positive patients seven days after beginning treatment, especially if those patients hadn't mounted a measurable immune response before beginning treatment.

Regeneron didn't set out to test REGN-COV2 as a treatment for seronegative patients, it was just a subgroup that appeared to perform really well during an interim analysis. Since this trial began in June, we've learned that COVID-19-positive patients usually reduce viral loads on their own once they're mounted an immune response. Around 45% of patients included in the initial analysis were already seropositive when they received REGN-COV2, which makes results from a limited sample size hard to interpret.

In the overall group, there was a significantly lower amount of SARS-CoV-2 floating around in patients seven days after they were randomized to receive a high dose of REGN-COV2, compared to patients who received a placebo. Unfortunately, reductions observed among patients who received a low dose of REGN-COV2 weren't strong enough to be considered statistically significant.

Test tubes

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Eli Lilly: LY-CoV555 and LY-CoV016

This summer, Eli Lilly and its collaboration partner AbCellera Biologics also began testing a pair of antibodies meant to neutralize SARS-CoV-2 by measuring viral load reductions 11 days after beginning treatment. Like Regeneron, Lilly found a majority of patients treated with placebos cleared the virus on their own. Despite the challenge, investigators measured a significant viral load reduction 11 days after patients began receiving LY-CoV555 and LY-CoV016 in combination.

Eli Lilly also measured significant symptom-score improvements among patients given the combo treatments, and an 84.5% hospital visit reduction. Patients given standard care plus a placebo ended up in the hospital for COVID-related reasons 5.8% of the time compared to just 0.9% of patients given the LY-CoV555 plus LY-CoV016 combo treatment.

Authorization requests

Eli Lilly began its antibody study in June with a group of patients who received LY-CoV555 on its own, and successful interim results have already led the company to request an emergency use authorization (EUA) from the Food and Drug Administration for LYCoV555 as a monotherapy. So far, trial results from patients given a combination of LY-CoV555 and Ly-CoV016 suggest the pair is more effective, and a subsequent EUA request for the antibody combination could happen in November.

The president recently said he had already authorized REGN-COV2, but this is the FDA's decision to make. It hasn't approved the EUA request for REGN-COV2 that Regeneron's submitted on Oct. 7.

Looking ahead

Given the positive snapshot we've seen from REGN-COV2's ongoing pivotal study, an EUA for Regeneron's candidate is probably right around the corner. This is a fairly reasonable expectation at this point because, unlike vaccines intended for healthy people, it's relatively easy to measure a benefit-to-risk ratio for treatment candidates given to COVID-19-positive patients.

Regeneron and Eli Lilly have made arrangements to begin mass distribution of their still-experimental treatment candidates before the ink on their EUAs goes dry. The companies haven't discussed pricing details regarding their respective COVID-19 treatment candidates, but investors probably shouldn't hold their breath for enormous financial windfalls. 

In the first half of 2020, Regeneron reported total sales that rose 24% year over year to $1.95 billion, and Eli Lilly's operations make Regeneron's seem modest. The pharma giant expects revenue to reach about $24 billion in 2020, without accounting for any contribution from LY-CoV555 and LY-CoV016.

Generally speaking, antiviral drugs that do their job with one short course of treatment are hard to sell at high prices in the face of competition. Regeneron and Eli Lilly are closest to the finish line, but they aren't the only big drugmakers with COVID-19 treatments near the finish line.