Mutations Targeted by Nous-209 Immunotherapy Occur Early in Lynch Syndrome Carriers' Precancer Lesions with Microsatellite Instability.

Neoantigen mutations targeted by Nous-209 vaccine are present early in MSI adenomas of Lynch MLH1/MSH2 carriers

50 adenomas and 12 advanced adenomas from 26 Lynch carriers (MLH1 or MSH2) were analyzed for MMR status, microsatellite instability, and presence of Nous-209 target mutations. 83% of advanced adenomas and 58% of simple adenomas are dMMR. Nous-209 target mutations strongly correlate with MSI status and are present from early precancerous lesions, biologically validating the preventive vaccine approach in Lynch syndrome.

Synthesis written by Geno'X. For the full original abstract, please refer to the source publication.

These data provide biological proof of concept that preventive immunization with Nous-209 could target lesions from their precancerous stage in Lynch — well before progression to invasive cancer. The early timing of these MSI mutations is a strong argument for vaccine trials in primary prevention among asymptomatic Lynch carriers.

Clinical impact: 2/3 · Evidence strength: 2/3 · Novelty: 2/2 · Sample size: 1/1 · Publication status: 0/1 → Total: 7/10