Last Friday, Merck and Ridgeback Biotherapeutics announced success with an antiviral pill called molnupiravir that’s proven to help curb COVID-19 infection at an early stage and keep patients out of hospital. The news sent a blow to vaccine stocks as investors anticipated the pill might give an option to people who are vaccine hesitant (although doctors say it doesn’t.) While that sentiment makes sense, it’s too early to project how big of a market molnupiravir will have.
Many factors are at play: When will Merck clear the FDA’s emergency use authorization? How will distribution be handled? Who is eligible to take the drug (Merck’s clinical trial was conducted entirely in unvaccinated patients) and how early in their infection course? And perhaps the most important question is: Will there be other COVID-19 drugs available soon?
Very likely. There are at least three potential COVID-19 therapies designed to treat early symptoms or prevent infections in the works that are expected to release test results before the end of 2021. Depending on their clinical data and regulatory progress, the options of COVID-19 treatments may look drastically different in a just few months.
Pfizer, so far the largest provider of COVID-19 vaccine in the developed world, is testing a pill that helps prevent infection when a person is in close contact with someone who’s caught the virus.
The pill, called PF-07321332, is designed to be taken in combination with a low dose of the antiretroviral HIV drug ritonavir. The drug hampers production of enzymes needed for the virus to multiply in human cells. Pfizer is currently testing the efficacy of this drug combo in people of age 18 and older who live in the same household with someone with a confirmed COVID-19 infection.
Pfizer began testing the drug in March and entered phase 2/3 trials last month. Participants in the late-stage trial who will be randomly assigned to receive either the pill or a placebo twice daily for five to ten days.
Pfizer expects to report trial results later this month and roll it out by year-end.
Atea and Roche: AT-527
Atea Pharmaceuticals and Roche are developing a COVID-19 antiviral called AT-527 that’s very similar to molnupiravir.
The partnering firms announced positive results for the drug in June. Data from phase 2 trials showed that in just two days the pill reduced COVID-19 in hospitalized patients by 80 percent compared to the placebo group. Within two weeks, the Roche-Atea pill completely cleared the coronavirus in 47 percent of patients, while only 22 percent of people in the placebo group were COVID-free by the end of the term.
More studies were needed for AT-527 to be used in mild symptom patients because the early analysis was conducted in hospitalized patients.
Roche and Atea expect to announce more results from phase 2 and phase 3 trials later this year.
AstraZeneca’s COVID-19 vaccine has yet to clear regulatory EUA in the U.S., but the British drugmaker said Tuesday it has asked the FDA to authorize an antibody drug called AZD7442 that has shown high efficacy in preventing symptomatic COVID-19.
Like a vaccine, AZD7442 is delivered as a shot. AstraZeneca reported strong clinical data on the antibody drug earlier this year. The company said the drug is designed for use in a minority of people with immune system diseases and other conditions that could render existing vaccines less effective.