Moderna (NASDAQ:MRNA) has been one of the fastest-moving organizations in the global competition to develop a vaccine for the SARS-CoV-2 coronavirus. It's currently gearing up for a phase 3 clinical trial of its investigational vaccine, mRNA-1273. The study, which it will conduct in collaboration with the National Institutes of Health, will enroll 30,000 participants in the U.S., each of whom will receive two doses of the vaccine, 28 days apart. And phase 3 is where the rubber meets the road. While its earlier trials were only testing for safety, side effects, and whether mRNA-1273 caused the subjects to develop the desired antibodies, in this trial the primary endpoint will be "the prevention of symptomatic COVID-19 disease."

In other words, does it work, and if so, how well?

Due to the speed of its efforts to develop a vaccine for COVID-19, Moderna's stock has soared by more than 220% since the year started. And what's more, several analysts have asserted that it has significant room to keep climbing. Last month, Goldman Sachs analyst Salveen Richter gave the stock a buy rating and a $105 price target, about 66.7% above the (roughly) $63 where it's currently trading. Analysts at Piper Sandler assigned the stock a $102 price target -- 61.9% above its current levels. With all this in mind, should you buy Moderna stock today? 

Microscopic view of the coronavirus.

Image source: Getty Images.

Is Moderna stock worth $105?

There is no question that Moderna's stock price will skyrocket if its vaccine candidate for the novel coronavirus is successful. Also, it has several other pipeline candidates. The company is currently developing a vaccine for the Zika virus, several cancer vaccines, and a cytomegalovirus vaccine, among many others. The best-case scenario for Moderna would be if mRNA-1273 is the first candidate to earn approval from the Food and Drug Administration, and proves at least as effective as any rival COVID-19 vaccines at preventing the illness -- and that the company goes on from that success to market several other blockbuster vaccines. If events play out that way, Moderna's stock will likely exceed the $105 mark. However, that scenario seems somewhat optimistic, in my view.

A lot could still go wrong for Moderna's potential vaccine for COVID-19. While it's preparing to start that phase 3 trial in July, it hasn't yet completed it phase 2 trial. The vaccine could fail to prove effective, which would cause Moderna's stock to plunge. Moreover, phase 3 vaccine trials don't have predetermined end dates. They run until enough participants in the placebo and vaccine arms have become infected with the disease that the developers can analyze how effective their vaccine candidate is.

Given that event-driven testing model, even with a later start, another company could leapfrog Moderna and launch a COVID-19 vaccine on the market first.

The company's other pipeline candidates -- none of which are in late-stage testing yet -- could also run into issues. Fewer than 10% of all vaccine candidates that start clinical trials succeed in getting regulatory approval. So while Moderna's stock will likely continue on its upward trajectory in the near term thanks to its COVID-19 vaccine efforts, it's still impossible to predict whether the company will maintain its momentum long enough for its shares to climb above $105. For that reason, I think Moderna remains a high-risk, high-reward biotech stock, and only those investors comfortable with that risk should consider initiating a small position in the company. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.