5 Early-Stage Cancer Immunotherapy Startups Rethinking Targeting

Why Bactheravax stands out

Bactheravax is attacking a source of treatment resistance that sits inside the tumor microenvironment rather than on the cancer cell itself. Its lead program targets Fusobacterium nucleatum, a bacterium associated with colorectal cancer progression, immune suppression and reduced treatment sensitivity.

The startup secured €350,000 from UNIIQ in 2026. Co-founder Dinja Oosterhoff previously helped advance a vaccine into Phase 1 testing, while Ivo Ploemen had negotiated more than $100 million in life-science licensing deals before Bactheravax.

What Bactheravax is building

Bactheravax is developing therapeutic vaccines designed to direct immune responses against bacteria living within tumors. The first program aims to reduce the influence of F. nucleatum in colorectal cancer and improve responsiveness to existing treatment.

The strategy creates an unusual immuno-oncology position: the therapeutic target is microbial, but the commercial endpoint is better cancer treatment.

Why Eris Biotech stands out

Eris Biotech is developing an oral route into immuno-oncology. Rather than adding another immune stimulant, it is trying to stop tumors from releasing signals that suppress immune recognition. Memorial Sloan Kettering Cancer Center selected the startup for its 2025 Therapeutics Accelerator cohort.

The founders bring cancer-immunology research backgrounds, and Eris Biotech was also selected for Y Combinator's Winter 2024 batch. That combination gives the startup both a defined biological hypothesis and external drug-development validation.

What Eris Biotech is building

Eris Biotech develops small-molecule inhibitors intended to block the formation and release of tumor-derived extracellular vesicles that suppress immune activity. Its lead work begins in mesothelioma.

If the mechanism translates, the appeal is straightforward: an oral molecule could make tumors more visible to the immune system without requiring a patient-specific manufacturing process.

Why Granza Bio stands out

Granza Bio is using a naturally occurring immune mechanism as a delivery platform. Its technology builds on attack particles released by cytotoxic immune cells, creating a route to package therapeutic cargo and direct it toward selected tissues.

The startup raised a $7.14 million seed round led by Felicis and Refactor Capital, with Y Combinator participating. Its scientific roots trace to research on attack particles at the University of Oxford.

What Granza Bio is building

Granza Bio is engineering protein shells that can carry therapeutic cargo, including RNA and proteins. Its cancer work uses synthetic attack particles designed to concentrate immune effects at selected disease targets.

The investment case therefore sits at the intersection of immunology and drug delivery: value depends not only on the payload, but on whether the platform can deliver it selectively enough to improve efficacy and safety.

Why Kopra Bio stands out

Kopra Bio combines viral delivery with local immune activation in one of oncology's hardest settings: glioblastoma. Its underlying research reported more than 90% long-term survival in treated mice, with surviving animals rejecting a later tumor challenge.

The startup raised $9.1 million in seed funding in June 2026. CEO Andrew Bartynski previously co-founded ANA Therapeutics, which was acquired by NeuroBo Pharmaceuticals, while Alexander Haddad was first author of the Nature Communications paper behind the platform.

What Kopra Bio is building

Kopra Bio is developing a replicating retroviral immunotherapy injected directly into tumors. Infected cancer cells produce an IL-15 superagonist, turning the tumor itself into a local source of immune stimulation. That local-production model is designed to solve two problems at once: distributing the therapy through dividing tumor tissue and limiting the need for broad systemic immune activation.

Why Nema Health stands out

Nema Health brings personalization to cancer vaccination. A €730,000 seed round was led by BCN Peptides, alongside a separate €335,000 NEOTEC grant, and the startup holds an exclusive licence to DIF peptide patents granted across six jurisdictions.

CEO Olga Rué Clarós previously led vaccine developer Archivel Farma for more than a decade, including clinical development of its RUTI tuberculosis vaccine. That operating history matters for a startup planning to build a preclinical package and then out-license.

What Nema Health is building

Nema Health is developing OncoNeoVac for advanced melanoma. The therapy combines patient-specific tumor neoantigens with DIF peptides derived from peripherin to provide individualized targets and stimulate an immune response.

The model is deliberately partnership-oriented: Nema Health plans to develop the preclinical evidence internally, then out-license the program for later-stage development and commercialization.