Moderna Stock Plunges 25% After Possible Cancer Vaccine Data Leak

Moderna's stock price dropped 25 percent after reports of a possible data leak involving its cancer vaccine research. The company had seen its stock rise significantly in 2026 due to investor confidence in this personalized cancer vaccine project. The sharp decline represents a reversal of that recent gains. It remains unclear what specific information may have been leaked or what consequences this will have for the company's vaccine development.