Moderna's Cancer Vaccine Update Fails to Boost Stock Performance

Moderna's shares fell despite promising results from a phase two trial of its personalized cancer vaccine developed with Merck. The vaccine, when combined with Merck's Keytruda, reduced the risk of recurrence of skin cancer melanoma by 44% compared to Keytruda alone. Nearly 80% of participants who received both the vaccine and Keytruda stayed cancer-free for 18 months. Moderna and Merck plan to initiate a phase three trial in 2023 and expand to study the treatment's effect on additional tumor types. Analysts remain cautiously optimistic about the treatment's potential, citing a long history of failures in the cancer vaccine space.