As the race for a coronavirus vaccine continues, Pfizer and BioNTech have officially entered their final trial phase Tuesday.

If things go well, vaccine authorization or approval would be next.

The decision to be one of nearly 30,000 people to participate in Pfizer and BioNTech's latest coronavirus vaccine trial phase was an easy one for Barry Colvin, of White Plains.

"I think it's important. There's a lot of people doing their parts. And theres a lot of us that are unable because we're either not in the health care field or not an essential worker or what have you, but there are other things we can potentially do," says Colvin.

As the companies take the big final step toward possibly becoming the solution to the coronavirus pandemic, Pfizer accepts the fact that all eyes are on them.

"This is the big test, so there's excitement but definitely some pressure as well," says Dr. Phil Dormitzer, vice president of viral vaccines for Pfizer.

Thousands of people between 18 and 85 will either get a dose of the vaccine or a placebo, and experts will see what happens.

Some trials will be in hot-spot zones to see how the vaccine shapes up in areas of high transmission..

"So this is the real test and there are no guarantees. We're optimistic. The immunodeficiency looks good. There are many things that look good. But you don't know until you really know and that's why you test," says Dormitzer.

News 12 was told the vaccine in previous phases has shown to produce antibodies at or above the level of someone who has recovered from the coronavirus, a positive immune cell response. While there have been some side effects like fever, fatigue and chill for one to two days after injection, there have been no serious adverse effects.

If things go well, Pfizer hopes to have some form of vaccine authorization as early as this October in order to supply the world with 100 million doses before the end of 2020.

While this process seems fast, Pfizer says it is following protocol outlined by the FDA.