Moderna Skyrockets 177% Following Historic mRNA Cancer Vaccine Breakthrough
In an unprecedented single-day stock surge in biotech history, Moderna (NASDAQ: MRNA) saw a 177% increase on August 19, 2026. This dramatic rise followed the announcement of overwhelmingly positive Phase 3 results for their personalized mRNA cancer vaccine, intismeran autogene, in a late-stage melanoma trial. This marks the first successful final-stage study for any mRNA-based cancer therapy.
Shares soared from $62.96 to a closing price of $174.38 on a record-breaking volume of 185.1 million shares. This volume is approximately 1,819% above the three-month average. The surge increased Moderna’s market capitalization from roughly $25 billion to nearly $69 billion in a single session, resulting in short sellers incurring losses of $5.5 billion. The rally also briefly propelled Moderna to a new 52-week intraday high of $176.66.
Investors are not only betting on the melanoma indication but also on Moderna’s broader oncology pipeline. Currently, the company has intismeran in multiple Phase 2 and Phase 3 cancer trials. Despite a partial pullback of approximately 20% the following day, the stock remains more than 155% above its pre-announcement close. Wall Street analysts are sharply divided, with fresh price targets ranging from $89 to $170. Detailed Phase 3 data is expected to be presented in October 2026.