Investors have had a lot to wrestle with lately, but on Monday morning, they got some good news. Although other major market benchmarks got most of the spotlight because they climbed to what would be new record levels, the Nasdaq Composite (NASDAQINDEX:^IXIC) nevertheless moved higher by about 0.5% as of 11 a.m. EST. That leaves the Nasdaq within 1% to 2% of putting up a record close of its own.

Yet within the Nasdaq, there's a tug of war going on. The market's broader gains are largely due to good news on the COVID-19 front from Moderna (NASDAQ:MRNA), which saw its stock rise again on Monday morning. Yet what's good news for companies hit hard by the pandemic has been hitting some stay-at-home stocks for a loop, especially Zoom Video Communications (NASDAQ:ZM). It's likely that as long as the coronavirus crisis is a prime factor in the market's day-to-day moves, investors will keep seeing these disparities inside the Nasdaq.

Two people pulling a rope in opposite directions, on a salt flat in a desert.

Image source: Getty Images.

Moderna lines up its coronavirus vaccine

Moderna was up 8% Monday morning after releasing the latest clinical study data about its coronavirus vaccine candidate. Shareholders were pleased to see efficacy figures that were better than expected.

Moderna's phase 3 COVE study of its mRNA-1273 vaccine candidate produced encouraging results in its first interim analysis. In particular, the study met its primary efficacy endpoint, with 94.5% effectiveness based on 95 confirmed cases of COVID-19 among an enrolled population of more than 30,000 U.S. participants. Of those 95 cases, 90 came from the placebo group, versus just five in the group receiving the vaccine candidate.

In addition, a secondary endpoint showed that none of the five COVID-19 cases in the vaccine group were severe. That compares to 11 severe cases in the placebo group. The study also didn't report any significant safety concerns at this interim point.

As a result, Moderna expects to submit paperwork to receive emergency-use authorization from the U.S. Food and Drug Administration within the coming weeks. The biotech company will seek similar approvals globally and expects to have 20 million doses ready for shipment in the U.S. by the end of 2020 and 500 million to 1 billion doses across the globe next year. That's good news for everyone around the world -- as well as Moderna shareholders.

Will leaving home hurt Zoom?

Meanwhile, Zoom Video Communications saw its stock lose 4% Monday morning. The video-collaboration specialist has proven its mettle during the coronavirus crisis, but an effective vaccine might end the stay-at-home movement and eat into Zoom's future growth.

To be clear, vaccines won't make a difference right away. Even announcements like Moderna's don't immediately make the vaccines available for general use, and navigating even an emergency process will take time. Moreover, vaccines won't be entirely effective, and that'll make it important to continue social distancing potentially for a year or longer.

Moreover, investors should remember that Zoom was already growing quickly even before COVID-19 appeared. The business world has long aimed to cut back on travel and improve collaboration. The coronavirus crisis merely accelerated that process, and businesses aren't suddenly going to go into reverse when health conditions get better. That should help Zoom keep growing even when workers start to return to the office.

Stay prepared

It's easy to look at the Nasdaq Composite as a single benchmark, but it's actually composed of many stocks with different reasons to invest. You should expect to see continued tension between vaccine producers like Moderna and stay-at-home stocks like Zoom for the foreseeable future -- until the COVID-19 pandemic ends once and for all.

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.