Merck and Moderna’s personalized mRNA melanoma vaccine cuts relapse risk by 42% in phase‑3 trial
Merck and Moderna presented phase‑3 data for their autogenous intismeran vaccine at the ESMO Congress on 24 October. In 1,137 high‑risk melanoma patients who had surgery, the vaccine combined with pembrolizumab reduced the risk of recurrence or death by 42 percent versus pembrolizumab alone. Two‑year relapse‑free survival was 82.2 percent with the vaccine versus 70 percent in the control arm. The therapy is complex and costly, and about 17 percent of screened patients were excluded because tumor samples could not yield suitable neoantigens.
Why it matters
The trial results triggered a sharp decline in Merck and Moderna shares after a leak on 22 October, reflecting investor concerns that the high price and manufacturing complexity may limit commercial upside. The data also highlight a potential new revenue stream for both companies if the vaccine gains regulatory approval, but the high cost could affect adoption rates.
Key facts
- 1The phase‑3 INTerpath‑001 trial enrolled 1,137 melanoma patients who had undergone surgery. thevermilion.com
- 2The vaccine plus pembrolizumab reduced the risk of relapse or death by 42 percent compared with pembrolizumab alone. thevermilion.com
- 3At two years, 82.2 percent of vaccinated patients were alive and relapse‑free versus 70 percent in the control group. thevermilion.com
- 4Approximately 17 percent of screened patients were excluded because tumor samples did not yield usable neoantigens. thevermilion.com
- 5The vaccine targets up to 34 patient‑specific neoantigens using an mRNA platform. oncodaily.com
- 6A leak of the results on 22 October caused a collapse in Merck and Moderna share prices. thevermilion.com
Summary written by AlphAI AI Desk from 2 of 2 sources. Not investment advice. Figures are as stated by the linked sources.