Pfizer has said its experimental antiviral pill for COVID-19 cuts risk rates of hospitalisation and death by nearly 90 percent, as drugmakers race to manufacture easy-to-use medication against the coronavirus.
The pharmaceutical giant released preliminary results of its study of 775 adults on Friday. Patients taking the company’s drug along with another antiviral were found to have had an 89 percent reduction in their combined rate of hospitalisation or death after a month, compared with patients taking a dummy pill.
Fewer than 1 percent of patients taking the drug needed to be hospitalised and no one died. In the comparison group, 7 percent were hospitalised and there were seven deaths.
“We were hoping that we had something extraordinary, but it’s rare that you see great drugs come through with almost 90 percent efficacy and 100 percent protection for death,” Mikael Dolsten, Pfizer’s chief scientific officer, told The Associated Press news agency.
Study participants were unvaccinated, with mild-to-moderate COVID-19, and were considered high risk for hospitalisation due to health problems like obesity, diabetes or heart disease. Treatment began within three to five days of initial symptoms and lasted for five days.
Of those given Pfizer’s drug within three days of symptom onset 0.8 percent were hospitalised and none had died by 28 days after treatment. That compared with a hospitalisation rate of 7 percent for placebo patients. There were also seven deaths in the placebo group.
Rates were similar for patients treated within five days of symptoms – 1 percent of the treatment group was hospitalised, compared with 6.7 percent for the placebo group, which included 10 deaths. Bourla said that works out to being 85 percent effective, Pfizer Chief Executive Albert Bourla said in an interview with US broadcaster CNBC.
Pfizer reported few details on side effects but said they were mild and rates of problems were similar between the groups at about 20 percent.
An independent group of medical experts monitoring the trial recommended stopping it early, as is standard procedure when interim results show a clear benefit.
Pfizer said it plans to submit interim trial results for its pill, which is given in combination with an older antiviral called ritonavir, to the US Food and Drug Administration (FDA) as part of the emergency use application it opened in October.
Once Pfizer applies, the FDA could make a decision within weeks or months.
The combination treatment, which will have the brand name Paxlovid, consists of three pills given twice daily.
Top US health officials have stressed that vaccination will remain the best protection against infection, but easy-to-use treatments will be critical to curbing future waves of contagions.
Merck, a competitor to Pfizer, reported in September that its pill cut rates of hospitalisation and death by 50 percent. Experts warn against comparing preliminary results because of differences in studies.
Although Merck’s pill is further along in the US regulatory process, Pfizer’s drug could benefit from a safety profile that is more familiar to regulators, raising fewer red flags.
The United Kingdom on Thursday became the first country in the world to approve the pill jointly developed by Merck and Ridgeback Biotherapeutics.
The Medicines and Healthcare products Regulatory Agency (MHRA) has recommended that the drug, molnupiravir, be used as soon as possible following a positive COVID-19 test and within five days of the onset of symptoms, citing clinical data.