A cancer vaccine developed by Merck and Moderna significantly reduced melanoma deaths compared to conventional treatments, according to data released Thursday. Although results met analyst expectations, an online leak prompted chaotic trading, causing Moderna's shares to sink 18 percent. The data was released early after trial details were leaked, though it was not scheduled for publication until Saturday.
Moderna's shares had more than doubled after the August announcement, but Thursday's drop erased much of those gains. The latest results provided more specific timing data on patient survival. After six months, the combination of mRNA and Merck's cancer-killing drug Keytruda reduced the risk of tumor recurrence or death by 58 percent.
The timing of recurrence-free survival was in line with estimates but failed to significantly improve upon Wall Street expectations. Evan Seigerman, analyst at BMO Capital Markets, stated the share price reaction "likely reflects inflated expectations into the full data release, rather than a true indictment of the efficacy of the combo therapy." Merck's shares dropped initially but recovered, ending the day down 1 percent. Moderna shares fell as much as 25 percent in intraday trading.
Analysts note it remains uncertain how the melanoma results can be applied to other cancers, as Merck and Moderna are also testing therapies in bladder and lung cancers. The published results were a final phase 3 trial underway since 2023, with the companies meeting US drug regulators and expecting approval next year.
Source: Financial Times Companies · Summarized by HeadlinesBriefing