SRTD Biotech raises €31.5M seed to advance mRNA switch therapies for cancer and autoimmune disease

SRTD Biotech (Jülich, Germany) has raised €31.5 million in an oversubscribed seed round to advance its platform for selectively expressed RNA (seRNA) — a class of mRNA therapeutics designed to activate only inside cells bearing a specific disease marker. The round was co-led by Mérieux Equity Partners (via its Mérieux Innovation 2 fund), NRW.BANK (via NRW.Venture EU Tech&Scale), and Boehringer Ingelheim Venture Fund, with Lilly Ventures, HTGF, and Jülich-based family office Anobis Asset also participating. Matthias Alder has joined as CEO and Heinz Koeppl as CTO alongside the close, with founders Bernd Hoffmann and Heribert Bohlen continuing with the company.

The seRNA mechanism

Standard mRNA therapeutics — including the COVID-19 vaccines that proved the modality — have no intrinsic cell-type preference. Delivered systemically, an mRNA construct can in principle express its payload in any cell that takes up the lipid nanoparticle. For vaccines, this is acceptable; for a cancer therapy or an autoimmune intervention, broad expression is a liability.

SRTD's approach builds a molecular gate into the mRNA construct itself. The seRNA remains inactive until it detects a specific RNA sequence — an endogenous marker associated with the target cell type or disease state — in the intracellular environment. Only when the internal trigger is present does the construct begin to express. The company is pursuing this across oncology, autoimmune disease, and fibrosis, where cell-type specificity could distinguish a therapeutic from a toxic dose.

Investor composition and next milestones

The round draws a mix of industrial and institutional validators. Boehringer Ingelheim Venture Fund and Lilly Ventures represent two of the largest pharmaceutical groups in mRNA-adjacent therapeutic development; both would have scrutinised the platform's production feasibility as well as its biology. NRW.BANK's participation via its EU Tech & Scale vehicle reflects the North Rhine-Westphalia policy interest in advanced manufacturing — Jülich hosts several Fraunhofer institutes relevant to bioproduction, and proximity to that infrastructure may be intentional.

HTGF, which led or participated in the founding round, is reinvesting, a signal that the science has held up through five years of internal review. The company has indicated it plans a larger round in 2027 contingent on GLP study data.

Why it matters

SRTD's seRNA concept addresses one of the core failure modes of mRNA therapeutics: systemic expression in cells that have no business receiving the payload. By engineering constructs that only activate when a specific endogenous RNA marker is detected, the platform aims to convert a potent modality into a targeted one. The seed round buys time to find out whether GMP production and GLP toxicology hold up. The 18-month test is whether GLP data can support an IND for the lead oncology programme without a materials science problem forcing a reformulation.