“Molnupiravir has been authorized for use in people who have mild to moderate COVID-19 and at least one risk factor for developing severe illness,” the government agency said in a news release, adding that regulators had conducted “a rigorous review” of the treatment’s safety and efficacy.
U.K. health officials said patients should seek the treatment “as soon as possible following a positive COVID-19 test and within five days of symptoms onset,” the release said.
British officials said in October that they had secured 480,000 courses of molnupiravir and hope to make the treatment available to patients this winter, according to the AP.
The pill has not yet been approved in the United States. Merck and Ridgeback submitted an application last month to the U.S. Food and Drug Administration seeking emergency use authorization for the treatment.
The U.K.’s move came just weeks after the companies said early results from their Phase 3 clinical trial showed that molnupiravir reduced the risk of hospitalization or death from the illness by about half in the study’s participants, who had underlying health conditions that put them at a higher risk of developing severe COVID-19.
The study tracked 775 adults who had mild to moderate COVID-19 infections and who began treatment with molnupiravir within five days of experiencing symptoms, according to an Oct. 1 news release. Through the 29th day of treatment, about 7% of patients who received the drug were hospitalized or died due to COVID-19, compared with 14% of patients who received a placebo, the release said. No deaths were reported in people who received molnupiravir, while eight deaths were reported in patients who got placebos, the companies said.
The study has not yet been peer-reviewed.
Last week, Merck announced it had signed a voluntary licensing agreement with the Medicines Patent Pool, a U.N.-backed public health organization, to let other drugmakers produce its pill. The move could help lower-income countries get better access to the treatment, the AP reported.
Photos: Elementary-age kids get their first COVID-19 vaccine shots Dr. Rhonda Achonolu comforts her son Amechi, 7, as he is inoculated with first dose of the Pfizer-BioNTech COVID-19 vaccine for children 5 to 11 years old at The Children's Hospital at Montefiore, Wednesday, Nov. 3, 2021, in the Bronx borough of New York. (AP Photo/Mary Altaffer)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Twins Ryann, left, and Jamie Onofrio Franceschini, 11, pose for a photo with Covid-19 vaccine stickers after being inoculated with the first dose of the Pfizer-BioNTech COVID-19 vaccine for children five to 12 years at The Children's Hospital at Montefiore, Wednesday, Nov. 3, 2021, in the Bronx borough of New York. (AP Photo/Mary Altaffer)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Carter Giglio, 8, joined by service dog Barney of Hero Dogs, shows off the bandaid over his injection site after being vaccinated, Wednesday, Nov. 3, 2021, at Children's National Hospital in Washington. (AP Photo/Carolyn Kaster)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Carter Giglio, 8, hugs Dr. Bear before being vaccinated, Wednesday, Nov. 3, 2021, at Children's National Hospital in Washington. (AP Photo/Carolyn Kaster)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Finn Washburn, 9, shows his vaccination site as his mother, Kate Elsley, takes a photo shortly after he received a Pfizer-BioNTech COVID-19 vaccine in San Jose, Calif., on Wednesday, Nov. 3, 2021. (AP Photo/Noah Berger)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Kidney transplant patient Sophia Silvaamaya, 5, held by her father Pedro Silvaamaya, is vaccinated by nurse Kelly Vanderwende, Wednesday, Nov. 3, 2021, at Children's National Hospital in Washington. (AP Photo/Carolyn Kaster)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Matthew Yip, 8, waits in line to receive a Pfizer-BioNTech COVID-19 vaccine in San Jose, Calif., on Wednesday, Nov. 3, 2021. (AP Photo/Noah Berger)
Photos: Elementary-age kids get their first COVID-19 vaccine shots A bandage is placed on Mackenzie Olson, 10, after receiving her COVID-19 vaccination at a pediatrician's office on Wednesday, Nov. 3, 2021, in Decatur, Ga. (AP Photo/Ron Harris)
Photos: Elementary-age kids get their first COVID-19 vaccine shots An excited Cate Zeigler-Amon, 10, hangs out of the car as she waits with her mom, Sara Zeigler, to receive her first dose of COVID-19 vaccine at the Viral Solutions vaccination and testing site in Decatur, Ga., on the first day COVID-19 vaccinations were available for children from 5 to 11 on Wednesday, Nov. 3, 2021. (AP Photo/Ben Gray)
Photos: Elementary-age kids get their first COVID-19 vaccine shots A vial of the Pfizer-BioNTech COVID-19 vaccine for children 5 to 12 years old is shown at the Viral Solutions vaccination and testing site in Decatur, Ga., Wednesday, Nov. 3, 2021. (AP Photo/Ben Gray)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Leah Lefkove, 9, shows off her vaccination sticker just before being the first child to be vaccinated at the Viral Solutions vaccination and testing site in Decatur, Ga., on the first day COVID-19 vaccinations were available for children from 5 to 11 on Wednesday, Nov. 3, 2021. (AP Photo/Ben Gray)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Dr. Rhonda Achonolu comforts her son Kenechi, 9, as he is inoculated with first dose of the Pfizer-BioNTech COVID-19 vaccine for children 5 to 11 years old at The Children's Hospital at Montefiore, Wednesday, Nov. 3, 2021, in the Bronx borough of New York. (AP Photo/Mary Altaffer)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Jill Holm-Denoma, left, holds her nearly 6-year-old son, Tyler, as he receives a COVID-19 vaccination from Emily Cole, a registered nurse at National Jewish Health, during the pediatric vaccine rollout Wednesday, Nov. 3, 2021, in east Denver. (AP Photo/David Zalubowski)
Photos: Elementary-age kids get their first COVID-19 vaccine shots This October 2021 photo provided by Pfizer shows kid-size doses of its COVID-19 vaccine in Puurs, Belgium. (Pfizer via AP, File)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Mackenzie Olson, 10, awaits her COVID-19 vaccination as her mother, Christine Olson, fills out paperwork at a pediatrician's office on Wednesday, Nov. 3, 2021, in Decatur, Ga. (AP Photo/Ron Harris)
Photos: Elementary-age kids get their first COVID-19 vaccine shots A child's dose of the COVID-19 vaccination is shown, Wednesday, Nov. 3, 2021, at Children's National Hospital in Washington. (AP Photo/Carolyn Kaster)
Photos: Elementary-age kids get their first COVID-19 vaccine shots Audrey Onaissi receives an injection of Pfizer-BioNTech COVID-19 vaccine in San Jose, Calif., on Wednesday, Nov. 3, 2021, as her sister Ava Onaissi, 8, waits her turn. (AP Photo/Noah Berger)
Photos: Elementary-age kids get their first COVID-19 vaccine shots An RN holds a vial with the Pfizer-BioNTech COVID-19 vaccine for children five to 12 years at The Children's Hospital at Montefiore, Wednesday, Nov. 3, 2021, in the Bronx borough of New York. (AP Photo/Mary Altaffer)