Monday's market meltdown pulled nearly every stock down. The operative word, though, is "nearly." A few stocks actually rose on a day when most stocks tanked.

Moderna (MRNA -2.53%) was one of those very few gravity-defying stocks. While the S&P 500 Index fell nearly 10% on Monday, Moderna's shares skyrocketed 33% higher. The small biotech hasn't exactly become a household name just yet, but there's a lot of buzz surrounding the company right now. Why are so many people talking about Moderna?

COVID-19 vaccine leaning on top of small toy wooden house with a doctor in the background

Image source: Getty Images.

The leader of the pack

The list of companies that are scrambling to develop vaccines for immunizing against COVID-19, the disease caused by the novel coronavirus that's now a pandemic sweeping across the world, reads like a "who's who" of the pharmaceutical industry. There's Johnson & Johnson, the biggest healthcare company on the planet. Big pharma companies including GlaxoSmithKline, Pfizer, and Sanofi are also in the race, as are small biotech Inovio Pharmaceuticals and Novavax.

But the leader of the pack, for now at least, is none other than Moderna. The company announced on Jan. 23 that it received funding from the Coalition for Epidemic Preparedness Innovations (CEPI) to develop a messenger RNA (mRNA) vaccine against the novel coronavirus. Moderna collaborated with the National Institute of Allergy and Infectious Diseases (NIAID), which is part of the National Institutes for Health (NIH), to design its experimental mRNA vaccine.

And now that vaccine is being tested for the first time in humans. Moderna reported on Monday that the first patient has been dosed in a phase 1 clinical study being conducted by the NIH. A total of 45 healthy adults are expected to participate in the study, which will include two vaccine doses spaced 28 days apart.

Thanks to its lead position in developing a COVID-19 vaccine, Moderna was even included among big pharma companies invited to the White House a couple of weeks ago to meet with President Trump and other top government officials to discuss how to combat the coronavirus outbreak. Moderna was, by far, the smallest of the seven drugmakers in this meeting.

Moderna's other candidates

Until recently, Moderna was best known (although not really well known) for another mRNA vaccine. The company is currently testing mRNA-1647 in a phase 2 study for vaccination against the cytomegalovirus (CMV). Interim results from this study are expected in Q3 this year.

Moderna has also attracted the interest of big drugmakers. It's working with Merck to develop an experimental cancer vaccine. AstraZeneca teamed up with Moderna to develop a regenerative drug targeting myocardial ischemia, a disease where blood flow to the heart muscle is blocked by plaque buildup in a coronary artery.

For a clinical-stage biotech, Moderna's pipeline is pretty robust. The company has a dozen other programs in clinical studies plus nine experimental drugs in preclinical testing.

Talk isn't cheap

But while everyone seems to be talking about Moderna these days, that talk isn't cheap. The biotech stock has soared 45% higher so far in 2020. Moderna's market cap now stands at nearly $10 billion.

That's an expensive valuation for a company that has no products on the market yet and no near-term prospects for launching a product. Investors are betting big-time that Moderna's coronavirus vaccine will be successful, but there's no guarantee that it will be. 

What if Moderna's vaccine does work well in immunizing against the novel coronavirus? The company could potentially be looking at a multibillion-dollar market. With that kind of opportunity, it makes sense for there to be a lot of buzz about Moderna -- even with the risks it faces.