---
description: Moderna/Merck intismeran encodes up to 34 patient-specific neoantigens and 5-year data shows sustained melanoma recurrence reduction with Phase 3 trials across NSCLC bladder and renal cancer and potential FDA approval by 2028
type: claim
domain: health
created: 2026-02-17
source: "Merck 5-year intismeran data announcement 2025; Scientific American personalized mRNA vaccines 2025; Fierce Biotech melanoma risk reduction data; Moderna pipeline disclosures 2026"
confidence: likely
---

# personalized mRNA cancer vaccines show sustained 49 percent reduction in melanoma recurrence after five years representing a genuinely novel therapeutic paradigm

The Moderna/Merck partnership on intismeran (mRNA-4157/V940) represents the most advanced non-COVID mRNA therapeutic and a genuinely novel approach to cancer treatment. The vaccine is manufactured individually for each patient: tumor DNA is sequenced, up to 34 neoantigens are selected, and personalized mRNA is produced to train the patient's immune system against their specific tumor mutations.

Five-year data showed sustained 49% reduction in melanoma recurrence risk when combined with Keytruda (pembrolizumab) versus Keytruda alone. The Phase 3 melanoma trial is fully enrolled with interim results expected in 2026. Phase 3 trials have been initiated in two NSCLC (lung cancer) settings, and 8 Phase 2/3 trials are underway across melanoma, NSCLC, bladder cancer, and renal cell carcinoma. Potential FDA approval could come as early as 2028.

The mRNA platform extends beyond cancer vaccines. Rare disease protein replacement (mRNA-3927 for propionic acidemia, mRNA-3705 for methylmalonic acidemia) uses mRNA to instruct cells to produce missing proteins -- a fundamentally new approach that doesn't permanently alter the genome but requires repeated dosing. Emerging RNA modalities including self-amplifying RNA, circular RNA, and siRNA expand the therapeutic toolkit further.

The 10-year trajectory: 5-10 approved mRNA products beyond COVID vaccines by 2035. Personalized cancer vaccines become standard adjuvant treatment for high-risk solid tumors. Combination respiratory vaccines (flu+COVID+RSV) simplify annual immunization. The wild card is autoimmune disease -- mRNA-based immune tolerance therapies could open an entirely new therapeutic category.

---

Relevant Notes:
- [[the healthcare cost curve bends up through 2035 because new curative and screening capabilities create more treatable conditions faster than prices decline]] -- personalized manufacturing for each patient is inherently expensive even at scale, creating a new $5-10B annual cost center by 2035
- [[gene editing is shifting from ex vivo to in vivo delivery via lipid nanoparticles which will reduce curative therapy costs from millions to hundreds of thousands per treatment]] -- mRNA and gene editing share LNP delivery infrastructure, forming a horizontal platform
- [[AI compresses drug discovery timelines by 30-40 percent but has not yet improved the 90 percent clinical failure rate that determines industry economics]] -- AI-accelerated neoantigen selection is critical to scaling personalized vaccine manufacturing

Topics:
- health and wellness
