Merck’s COVID-19 pill molnupiravir can reduce the risk of hospitalisation and death when taken soon after contracting COVID-19, according to the results of its phase 3 trial which were announced by the company last month but have now been published in a peer-reviewed journal.

An interim analysis had initially suggested molnupiravir reduced the risk of hospitalisation and death by 50 per cent, but the results of the full study now show that this figure is closer to 30 per cent.

A total of 1433 volunteers underwent randomization; 716 were assigned to receive molnupiravir and 717 to receive placebo. With the exception of an imbalance in sex, baseline characteristics were similar in the two groups.

The superiority of molnupiravir was demonstrated at the interim analysis; the risk of hospitalization for any cause or death through day 29 was lower with molnupiravir (28 of 385 participants [7.3%]) than with placebo (53 of 377 [14.1%]) (difference, −6.8 percentage points; 95% confidence interval, −11.3 to −2.4; P=0.001).

In the analysis of all participants who had undergone randomization, the percentage of participants who were hospitalized or died through day 29 was lower in the molnupiravir group than in the placebo group (6.8% [48 of 709] vs. 9.7% [68 of 699]; difference, −3.0 percentage points; 95% confidence interval, −5.9 to −0.1).

Results of subgroup analyses were largely consistent with these overall results; in some subgroups, such as patients with evidence of previous SARS-CoV-2 infection, those with low baseline viral load, and those with diabetes, the point estimate for the difference favored placebo.

One death was reported in the molnupiravir group and 9 were reported in the placebo group through day 29. Adverse events were reported in 216 of 710 participants (30.4%) in the molnupiravir group and 231 of 701 (33.0%) in the placebo group.

The full study showed that 6.8 per cent of the molnupiravir group were hospitalised or died in the first month, compared to 9.7 per cent in the placebo group.

Nine people treated with the placebo died, and one person treated with molnupiravir died during the same period.

Source: 10.1056/NEJMoa2116044

You were reading: Peer-reviewed: Merck’s COVID-19 pill molnupiravir efficacy drops to 30%