Star coronavirus stocks Moderna (MRNA 0.59%) and Pfizer (PFE -1.49%) were outpaced by the S&P 500 index on Monday. Although both rose -- Moderna closed the day 1% higher while Pfizer inched up by 0.7% -- the bellwether stock index advanced nearly 2%. There was a notable development on the regulatory front for both companies, but investors clearly didn't find it overly encouraging.
That seems to be a reaction to the news that the Food and Drug Administration (FDA) has set a meeting for its expert advisory committee on vaccines to review fresh clinical data for Pfizer and Moderna's coronavirus jabs.
Moderna's mRNA-1273 (also known as Spikevax) and Pfizer's Comirnaty, developed in partnership with German biotech BioNTech (BNTX 1.49%), are the only two FDA-approved COVID-19 shots. A third, from Johnson & Johnson unit Janssen, holds Emergency Use Authorization (EUA).
The advisory committee meeting, set for June 15, is aimed at determining a recommendation for two vaccines to be administered to infants and toddlers under an EUA. The FDA's announcement came shortly after Pfizer and BioNTech unveiled the results of a phase 2/3 clinical trial on that patient population.
According to the two companies, Comirnaty showed efficacy of just over 80% in that age group. It also produced "a strong immune response, with a favorable safety profile similar to placebo," Pfizer said.
It's a bit surprising that investors weren't more bullish on this news. Perhaps their optimism is tempered by the fact that the committee meeting is taking place in a matter of weeks rather than days -- although by the standards of a big regulator, this one is being arranged relatively quickly.
Another reason might be that both the good clinical results of the latest Comirnaty trial and the FDA's convening of the committee were more or less expected. Regardless, this new development bodes well for both Moderna and Pfizer (and BioNTech, it probably goes without saying), so investors in all those companies have yet another reason to hang on to their shares.