Leaked Moderna–Merck Melanoma Vaccine Data Sparks Doctor–Market Split


Leaked trial data on Moderna and Merck’s melanoma vaccine prompted clinician praise but triggered a Wall Street sell-off, revealing a rare disconnect ahead of the formal ESMO presentation.

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What stands out

Bloomberg reports that leaked efficacy data from Moderna and Merck’s melanoma vaccine trial produced a sharp split: oncologists publicly praised the results, while Wall Street sold the stocks after the details hit social media ahead of the planned European Society for Medical Oncology presentation. The clip highlights a rare mismatch between clinical enthusiasm and market reaction, driven by the timing and informality of the leak rather than the full, peer-reviewed data set. The footage captures how premature disclosures can create confusion among clinicians, investors, and conference organizers.