Pfizer plans to make its COVID-19 vaccine available to more groups of people, including children as young as 12.

On Monday, Pfizer announced on its website that it got approval from the regulators to widen its trial of the COVID-19 shot that will include children ages 12 and above.

The plan is the first major drugmaker to start the COVID-19 vaccine trial for children. Pfizer also got approval to expand the study to include as many volunteers as 48,400 or 10% larger than the previous cap, the Pfizer spokesperson said.

According to Business Insider, in September, the New York-based company expanded the trial to include 16-and-17-year-olds and people with hepatitis B, hepatitis C, or HIV. Pfizer is the leading company in developing a COVID-19 vaccine.

In July, the company started the final stage of vaccine trials. It has said that it expects to know if the shot will work by the end of the month. Vaccine research has predominantly focused on adults so far.

There are two reasons why the coronavirus vaccine research started with adults. First, COVID-19 disease has been shown to have the most risk for the elderly. Besides, younger people showed much better recovering rates from the virus.

Secondly, vaccines are commonly tested gradually. It starts with the healthiest and less-vulnerable people. As data increases, indicating the shots are safe, they work with more vulnerable populations that will be added to the trials.

FDA Clears Way for Pfizer COVID-19 Vaccine, Millions of Doses To Be Shipped Right Away
Pfizer Makes $1.95 Billion Deal With U.S. For Future COVID-19 Vaccine NEW YORK, NY - JULY 22: Pfizer Inc. signage is seen on July 22, 2020 in New York City. Pfizer and German biotechnology firm BioNTech have agreed to supply the U.S. government with 100 million doses of coronavirus vaccine under a $1.95 billion deal. Jeenah Moon/Getty Images

However, having the COVID-19 vaccine for children is still crucial in fighting the coronavirus pandemic, particularly in helping schools reopen safely.

On the other hand, Moderna, Massachusetts-based biotech said that it plans to start a pediatric trial for its COVID-19 vaccine before the year ends. The company is still waiting for approval from the regulators. In July, Moderna's final stage of COVID-19 vaccine trials started, and it expects to have efficacy results by November.

Moncef Slaoui, the chief scientist overseeing the US government's COVID-19 vaccine initiative, told Business Insider that he believes that a vaccine needs to show it works in adults prior to being tried in large numbers children.

Paul Stoffels, Johnson & Johnson Chief Scientific Officer, said J&J is also committed to conducting pediatric trials. Stoffels noted on a September 22 call with the reporters that the opening of studies for children will come before the year ends. In September, J&J started the final stage of COVID-19vaccine trials.

Channel News Asia reported that earlier this month, the head of the World Health Organization (WHO) said that a vaccine against the coronavirus disease might be ready by the end of the year.

The WHO's COVAX global vaccine facility has nine experimental vaccines in the pipeline. It aims to distribute two billion doses before 2021 ends. On Monday, the group's chief scientist said that more than 180 countries also committed to joining in WHO's effort to finance COVID-19 vaccines to be fairly distributed to both poor and rich countries.

Check these out:

Diabetes Drug Metformin Hydrochloride Recalled Over Possible Cancer-Causing Ingredient

Pure Obsessive-Compulsive Disorder: How to Recognize the Symptoms

COVID-19 Patient Suffers Brain Damage Following Infection, Makes Scientists Concerned