Shares of the pharmaceutical heavyweight, which saw its profile and revenue explode thanks to its development of one of the first mRNA-based COVID vaccines, were down more than 10% in premarket trading Friday after Morgan Stanley warned the early-stage flu vaccine trial data had disappointed analysts who were looking for "clearly better efficacy."

Instead, the Moderna shot appears to only match results from Sanofi's Fluzone HD.

Moderna management "didn't provide detailed reactogenicity data or data on seroconversion which we expect in the slides from the call," said analyst Matthew Harrison, who has an equal-weight rating on the stock with a price target $313.

The news sent Moderna shares tumbling toward their lows from early last month, when the firm's Q3 earnings report, particularly its sales guidance for the coming year, missed Wall Street expectations.

And now, it appears the company's attempt to diversify away from its COVID business is already struggling to compete.

No wonder why Moderna CEO Stephane Bancel has been spreading nonstop FUD about the omicron variant and talking up the need for more jabs (Moderna, Pfizer and other major vaccine producers have all promised to have an omicron-targeting jab ready in three months).