ESMO 2026: Merck, Moderna shares fall as cancer vaccine disappoints after data leak
Published . Updated .
A combination of the personalized cancer vaccine intismeran autogene and Merck's Keytruda just barely cleared analysts’ expectations for recurrence-free survival, leaving questions as to its applicability to tumor types beyond melanoma.
Directly affected
Indirectly affected
- SPY SPDR S&P 500+1.6%
The broad U.S. stock market
- TLT iShares 20+ Year Treasury Bond-1.8%
Long-term U.S. government bonds
- QQQ Invesco QQQ+2.3%
Large technology stocks
- GLD SPDR Gold Shares-3.3%
Gold can move with the broad market
Price reaction, T-5 to T+3
| Ticker | T-5 | T-3 | T-1 | T0 | T+1 | T+2 | T+3 |
|---|---|---|---|---|---|---|---|
| MRK | -0.83% | +0.72% | base | after close | after close | after close | after close |
| MRNA | +7.22% | +19.41% | base | after close | after close | after close | after close |
| SPY | -0.09% | +0.66% | base | after close | after close | after close | after close |
| TLT | -2.07% | -1.97% | base | after close | after close | after close | after close |
| QQQ | +0.75% | +1.80% | base | after close | after close | after close | after close |
| GLD | +3.51% | +2.33% | base | after close | after close | after close | after close |
Closing-price change versus T-1, the last close before the story. T0 to T+3 fill in after each market close. Prices: Alpaca IEX.
Market Call
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ESMO 2026: Merck, Moderna shares fall as cancer vaccine disappoints after data leak BioSpace
Source: BioSpace
This story
| Company | When | Move | Status |
|---|---|---|---|
| GLD | three days earlier | +2.33% | final price |
| GLD | five days earlier | +3.51% | final price |
| MRK | three days earlier | +0.72% | final price |
| MRK | five days earlier | -0.83% | final price |
| MRNA | three days earlier | +19.41% | final price |
| MRNA | five days earlier | +7.22% | final price |
| QQQ | three days earlier | +1.80% | final price |
| QQQ | five days earlier | +0.75% | final price |
| SPY | three days earlier | +0.66% | final price |
| SPY | five days earlier | -0.09% | final price |
| TLT | three days earlier | -1.97% | final price |
| TLT | five days earlier | -2.07% | final price |
Trades by members of Congress and officials in the stocks in this story
- Rep. Maria Elvira Salazar sold Merck (MRK), worth $1,001 - $15,000 on 24 Sep 2026. That is 28 days before publication. Filed 7 Oct 2026. View the filing.
- Rep. Maria Elvira Salazar bought Merck (MRK), worth $15,001 - $50,000 on 19 Aug 2026. That is 64 days before publication. Filed 9 Sep 2026. View the filing.
- Rep. Maria Elvira Salazar sold Moderna (MRNA), worth $1,001 - $15,000 on 24 Sep 2026. That is 28 days before publication. Filed 7 Oct 2026. View the filing.
- Rep. Rohit Khanna bought Moderna (MRNA) (held by a spouse), worth $1,001 - $15,000 on 4 Sep 2026. That is 48 days before publication. Filed 7 Oct 2026. View the filing.
- Donald J Trump, an executive branch official, bought Moderna (MRNA), worth $1,001 - $15,000 on 28 Aug 2026. That is 55 days before publication. Filed 8 Oct 2026. View the filing.
Public disclosure filings, not a recommendation. The filing link is the source document. News use of these reports still sits under 5 U.S.C. § 13107(c).
This story
12 out of 100
“ESMO 2026: Merck, Moderna shares fall as cancer vaccine disappoints after data leak” scores 12 out of 100. The score uses 1 sources.