Moderna’s stock fell more than 16% in early U.S. trading Thursday after surging 177% the prior session on positive late-stage trial data for its personalized mRNA cancer vaccine, intismeran.
The rally followed the release of trial results showing that intismeran, developed in partnership with Merck, significantly slowed the spread and recurrence of melanoma in high-risk patients who had undergone surgery. The vaccine met its primary endpoint by extending recurrence-free survival, marking a second major oncology breakthrough in recent months after a separate drug demonstrated improved survival rates in pancreatic cancer patients.
Bank of America analyst Alec Stranahan raised Moderna’s price target to $170 from $40 and reiterated a Buy rating on Merck with a $166 target. The analyst’s model projects global peak sales of $54 billion for intismeran, with Moderna and Merck splitting economics evenly. Stranahan noted that a hazard ratio of at least 0.8 on recurrence-free survival could support adoption, while a ratio of 0.6 to 0.7, expected to be presented at the European Society for Medical Oncology conference, would likely prompt further upgrades.
Morgan Stanley also upgraded Merck to Overweight from Equal Weight, lifting its price target to $179 from $116. However, RBC Capital Markets downgraded Merck to Sector Perform from Outperform, citing an "unprecedented valuation" for a company facing a significant loss of exclusivity within two years and modest interim growth prospects.
Merck’s shares slipped 1.5% on Thursday after rising 12.6% the previous day alongside Moderna’s surge. The biotech’s rapid ascent underscores investor optimism around the potential of personalized mRNA therapies in oncology, though the subsequent pullback reflects volatility tied to clinical and commercial uncertainties.
