Crossbow Therapeutics Secures $77M to Target Untouchable Cancer Proteins

CAMBRIDGE, Mass. – March 18, 2026 – Crossbow Therapeutics has secured $77 million in a Series B financing round, a significant capital injection designed to advance its novel class of antibody therapies that aim to attack cancer cells by targeting proteins previously considered unreachable. The financing, co-led by strategic investors Taiho Ventures and Arkin Bio Capital, will fuel the clinical development of the company's lead candidates and accelerate its mission to expand the arsenal of cancer immunotherapy.

The funding validates Crossbow's innovative approach and provides the runway to complete a critical Phase 1 clinical trial for its lead program, CBX-250, while also advancing a second promising therapy, CBX-663, toward human studies. The company’s technology seeks to overcome a fundamental limitation of many current cancer drugs, potentially opening up new avenues of treatment for patients with aggressive and hard-to-treat malignancies.

Unlocking the Intracellular Universe

At the heart of Crossbow's strategy is its proprietary T-Bolt™ platform, which engineers T-cell receptor (TCR)-mimetic antibodies. Unlike conventional antibody therapies that can only recognize targets on the surface of a cell, Crossbow's molecules are designed to identify protein fragments from inside the cancer cell that are presented on its surface. These fragments, known as peptide human leukocyte antigen (pHLA) complexes, act as unique flags for cancer, offering a way to distinguish malignant cells from healthy ones with high precision.

This approach effectively unlocks the entire intracellular proteome as a source of therapeutic targets, a vast landscape that has remained largely “undruggable” by traditional antibody-based medicines. By mimicking the natural surveillance function of T-cells, Crossbow’s T-Bolt™ therapies are designed to act as bispecific T-cell engagers (TCEs), physically linking a patient’s own immune T-cells to the cancer cell to trigger a potent and targeted killing effect.

“This financing not only strengthens our ability to advance CBX-250 through clinical development but also accelerates our mission to bring next-generation TCR-mimetic immunotherapies to patients who urgently need new options,” said Briggs Morrison, M.D., Chief Executive Officer of Crossbow Therapeutics. “We greatly appreciate our investors for sharing our conviction in the transformative potential of our T-Bolt™ platform.”

A Vote of Confidence from Strategic Investors

The composition of the investor syndicate underscores the perceived potential of Crossbow's technology. The round was co-led by Taiho Ventures, the corporate venture arm of Japanese oncology-focused Taiho Pharmaceutical, and Arkin Bio Capital, a global fund specializing in guiding clinical-stage companies toward key milestones. Their leadership, alongside participation from new investors like Sixty Degree Capital and LifeLink Ventures, signals strong confidence from backers with deep expertise in drug development and the oncology market.

Crucially, the round also saw continued participation from existing investors who seeded the company’s $80 million Series A round in 2023, including MPM BioImpact and the venture arms of pharmaceutical giants Pfizer and Eli Lilly and Company. This sustained support from major industry players provides powerful validation of the platform's scientific and commercial promise. As part of the financing, Sakae Asanuma, President & CEO of Taiho Ventures, and Pini Orbach, Managing Partner of Arkin Bio Capital, will join Crossbow’s Board of Directors, adding significant strategic and developmental experience.

“Crossbow’s arsenal of T-cell engagers represents a differentiated and promising approach to anti-cancer immunotherapy by addressing the wide variety of intra-cellular targets and broadens the potentials of TCE modality,” commented Sakae Asanuma. “The company’s experienced team and versatile platform position it to overcome the limitations of current treatments and deliver impact for patients in need.”

Advancing a Pipeline for High-Need Cancers

The $77 million will be deployed to hit critical clinical milestones for Crossbow's two lead programs. A significant portion is allocated to completing the Phase 1 CROSSCHECK-001 trial for CBX-250. This first-in-class therapy targets a pHLA specific to myeloid cancer cells and is being evaluated in patients with relapsed or refractory myeloid malignancies, including acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and chronic myeloid leukemia (CML). These diseases, particularly in their advanced stages, have grim prognoses and a desperate need for new therapeutic options. The company expects to report initial clinical data from this trial around the end of 2026.

Furthermore, the financing will enable Crossbow to push its second asset, CBX-663, into the clinic. This therapy targets a peptide derived from telomerase reverse transcriptase (TERT), an enzyme that is reactivated in approximately 90% of all human cancers but is largely dormant in healthy adult cells. This makes TERT an exceptionally attractive, broadly applicable cancer target. By aiming at a TERT-derived pHLA, CBX-663 holds the potential to treat a wide array of both hematologic and solid tumors. Crossbow plans to submit an Investigational New Drug (IND) application and initiate a Phase 1 trial for CBX-663 in the third quarter of 2026.

To further build the scientific case for its platform, Crossbow is scheduled to present preclinical findings for both programs at the upcoming American Association for Cancer Research (AACR) 2026 Annual Meeting in San Diego. Researchers will deliver an oral presentation on CBX-250’s performance in models of acute myeloid leukemia and a poster presentation detailing the characterization of CBX-663 in preclinical solid tumor models, offering the broader scientific community a first look at the data underpinning this next-generation approach to cancer therapy.