The United Kingdom on Thursday became the first country in the world to approve a pill to treat mild to moderate Covid-19.

The country’s Medicines and Healthcare Products Regulatory Agency approved the drug molnupiravir, an antiviral pill developed by United States-based pharmaceutical company Merck and biotechnology company Ridgeback Biotherapeutics.

The pill can be given to adults who test positive for the coronavirus, and have at least one risk factor for developing severe infection, the company said in a press release.

Robert M Davis, the CEO of Merck, said that the company will act with both rigour and urgency to bring molnupiravir to patients around the world as quickly as possible.

The company’s Executive Vice-President Dean Li said that the drug “offers an important addition” to the vaccines and medicines used so far to treat Covid-19.

“We are very grateful to the investigators, patients and their families for their critical contributions to the [study] that made this authorization possible,” he said.

The United Kingdom government’s authorisation was based on a clinical trial that studied the effect of the drug among non-hospitalised and unvaccinated adult persons who had contracted Covid-19 up to five days before the analysis began.

The participants had at least one risk factor for severe illness, such as heart disease or diabetes.

The study showed that molnupiravir reduced the risk of hospitalisation and death by about 50% as compared to those who received a placebo.

United Kingdom Secretary of State for Health Sajid Javid said that the decision will protect the “country’s most vulnerable” and that the government is working “at pace” to make the pill available.

“Getting your vaccine is still the most important thing that we can all do right now to protect ourselves and our loved ones,” he said. “So please, whether it is your first, your second or your booster dose, get it booked and get vaccinated

The United Kingdom has agreed to buy about 4,80,000 pills and the first deliveries will begin by the middle of November, the BBC reported.

On Wednesday, the country registered 41,229 coronavirus cases and 217 fatalities.