Moderna Stock Reverses Hard After Historic One-Day Spike
Phase 3 printed. The stock went vertical. Thursday it gave a large piece of it back. That is a digestion day, not a new trial failure.
Wednesday was a real trial day. Merck and Moderna said Phase 3 INTerpath-001 — intismeran autogene (V940 / mRNA-4157) plus Keytruda versus Keytruda alone in 1,137 patients with completely resected stage IIB–IV melanoma — met recurrence-free survival and distant metastasis-free survival at a pre-specified interim. The companies called it the first positive Phase 3 for an individualized neoantigen therapy and for an mRNA cancer shot. That print is why the stock went vertical. It is still why the stock exists at these prices.
The move was historic. Barron’s put Wednesday at +177%. Clinical Trials Arena had the Aug. 18 close at $62.96 and the Aug. 19 open at $116.25 — 84% overnight — then $141.78 by 11:30 a.m. ET. Reuters had a two-year high of $140.19 and about $30 billion of market cap added, with volume more than 15 times the 50-day average. Merck rallied as much as ~10–12.5% depending on the desk. Short interest was 13.5% of free float (ORTEX via Reuters). That is a squeeze sitting on top of a trial.
What Thursday is not
It is not a second press release. Schwab had MRNA more than 9% lower in Thursday pre-market after the 177% day. Secondary recaps described a mid-teens to ~25% session fade. Those prints do not agree, so we will not pick one and pretend it is the close. What they agree on is direction: the tape gave back a large piece of Wednesday. That is what a 177% large-cap day does when the buyers were shorts covering and momentum chasing the same print.
The science did not reverse. INTerpath-001 still hit. Overall survival is still a later endpoint. Manufacturing an individualized shot is still the commercial risk the sell-side already knew on Wednesday afternoon. Thursday is the market deciding that 177% priced a launch that has not filed yet.
How to sit MRNA from here
If you wanted the Phase 3, you got it on Wednesday. If you wanted the equity at $62.96, that tape is gone. The honest hold is through the full data, the regulatory path, and a manufacturing story that Phase 3 success does not magically solve. The honest trade was Wednesday. Do not confuse a digestion day with a failed trial.
The honest takeaway: the melanoma shot worked in Phase 3. The stock made a historic one-day high and then reversed hard. Those are two different prints. Only one of them is the drug.