Nouscom raises €120m to take Lynch syndrome cancer vaccine into a registration trial

Basel-based Nouscom has raised €120 million ($135 million) in a Series D round to put NOUS-209, its off-the-shelf vaccine meant to stop cancer developing in people with Lynch syndrome, into a global registration-enabling trial ¹. M Ventures and Revelation Partners led the round, which was announced on 19 October 2026 ¹².

What the vaccine is and what the data show

NOUS-209 uses two viral vectors to deliver 209 shared frameshift peptide neoantigens. It is aimed at tumours with mismatch repair deficiency and microsatellite instability, and the intent is to prime the immune system against precancerous and cancerous cells before a tumour forms ¹. The neoantigens it targets are found in cancerous cells and absent from healthy ones ².

Nouscom released early clinical evidence alongside the financing. In a phase 1b/2 trial, all evaluable Lynch syndrome carriers given the vaccine were free of advanced adenomas and colorectal cancer. The company has one-year data on 43 patients and two-year data on 17 ¹. Freedom from disease was judged by colonoscopy, and the new data are due at the ESMO congress in Madrid later this week ². The trial also showed broad and durable T-cell responses against the neoantigens, and annual retreatment strengthened them ¹. Nouscom compared the results with the cancer incidence expected in carriers and described a signal of durable clinical activity ¹.

The target population is large and mostly undiagnosed. Fierce Biotech reports a 50% to 80% lifetime risk of colorectal cancer and a 40% to 60% risk of endometrial cancer for people with the syndrome, which it says affects nearly a million people in the US ¹. Pharmaphorum, citing Nouscom, puts the US figure at 1.1 to 1.2 million and says as many as 95% may not know they carry it, because genetic testing is rarely done without a family history of early-onset cancer ².

What it means for the market

The round moves a cancer-prevention vaccine into the stage that decides whether it can be filed. New investors Angelini Industries, the European Investment Bank and Italian venture firm Neva SGR joined, alongside existing backers including 5AM Ventures and Andera Partners ¹. The European Investment Bank's presence puts public European money behind a late-stage European biotech programme.

For developers, the deal is a test of a different design choice in cancer vaccines. Merck & Co. and Moderna build their vaccine for each patient's tumour, and their phase 3 melanoma data recently raised expectations for the field ¹. Nouscom's lead product is the same for every patient, built on the finding that Lynch syndrome patients share recurrent neoantigens ¹. An off-the-shelf product, if it works, avoids making a new batch per patient. Fierce Biotech notes that cancer vaccines as a class have a long and largely unsuccessful history ¹.

A prevention trial in a mostly undiagnosed population also raises a question the sources leave open: how carriers would be found and enrolled at scale, given how rarely testing is done today ².

Caveats

The evidence so far is early. The phase 1b/2 data cover 43 patients at one year and 17 at two years, with no control arm described in the sources, and the activity signal rests on comparison with expected incidence rather than a randomised result ¹. The trial design, size and start date of the registration-enabling study are not given. The next point of reference is the long-term data at ESMO in Madrid this week ².