Roundup of Antibody Biotech Deals in May 2026

May 2026 saw deal activity across oncology, immunology, infectious disease, and autoimmune indications. Large strategic collaborations highlighted continued pharma interest in ADCs, multispecific antibodies, T-cell engagers, and antibody-based delivery platforms. 

🔍 May Deal Signals

1. Large pharma partnerships continued to focus on antibody-based pipelines, especially ADCs and multispecifics, with up to $15.2B deals

2. China-based biotech and pharma companies remained active partners in major global antibody deals 

3. T-cell engagers have applications beyond oncology, including autoimmune disease 

4. ADCs and antibody conjugates continued to diversify, including dual-payload ADCs and antibody-helicon conjugates 

💰 Mergers & Acquisitions

• UCB × Candid Therapeutics – UCB agreed to acquire Candid Therapeutics for $2.2B to expand its immunology pipeline with T-cell engagers for autoimmune diseases. Candid’s lead asset, cizutamig, is an anti-BCMA/anti-CD3 bispecific antibody. 

• InMed Pharmaceuticals × Mentari Therapeutics – InMed Pharmaceuticals and Mentari Therapeutics announced a merger to advance migraine prevention antibody therapies; the transaction was valued at approximately $290M. 

• Liminatus Pharma × InnocsAI – Liminatus announced a proposed $320M merger with InnocsAI to expand its oncology cell therapy pipeline and combine CAR-T and antibody-related technologies. 

🤝 Strategic Collaborations & Licensing

• Bristol Myers Squibb × Hengrui Pharma – BMS and Hengrui entered a strategic collaboration covering 13 assets across oncology, hematology, and immunology, with a total potential value of up to $15.2B. 

• Pfizer × Innovent Biologics – Pfizer and Innovent entered a global strategic collaboration to develop up to 12 antibody drugs, including ADCs and multispecific antibodies. The deal value could reach up to $10.5B. 

• Regeneron × Parabilis Medicines – Regeneron and Parabilis announced a $2.3B strategic collaboration to advance novel antibody-helicon conjugates across multiple therapeutic areas. 

• Boehringer Ingelheim × Immunitas Therapeutics – Boehringer Ingelheim licensed a preclinical antibody program from Immunitas Therapeutics to advance treatments for chronic inflammatory diseases. The agreement is valued at up to €407.5M. 

• Context Therapeutics × BioAtla – Context Therapeutics amended its license agreement with BioAtla to obtain full rights to CT-202, a Nectin-4 × CD3 T-cell engager bispecific antibody, for $6.5M. 

• Delos Capital × AP Biosciences – Delos Capital and AP Biosciences launched a collaboration to create new biotech companies focused on autoimmune diseases using next-generation bi- and tri-specific antibodies. 

• Whitehawk Therapeutics × Hangzhou DAC – Whitehawk expanded its ADC pipeline through a new option agreement covering up to five ADC programs, including dual-payload ADC variations. 

💵 Financings & Company Launches

• Apogee Therapeutics × Blackstone Life Sciences – Apogee announced a $1.3B strategic financing collaboration with Blackstone Life Sciences to support Phase 3 development and commercialization of zumilokibart, an anti-IL-13 monoclonal antibody for atopic dermatitis. 

• Windward Bio – Windward Bio secured $165M in crossover financing to advance two clinical-stage long-acting antibody programs for immunology indications. 

• Cytospire Therapeutics – Cytospire raised an oversubscribed £61M, or approximately $83M, Series A financing to advance first-in-class pan-gamma delta T cell engagers into clinical trials for cancer. 

• LTZ Therapeutics – LTZ Therapeutics raised $38M to advance its myeloid engager immunotherapy pipeline, including LTZ-301, a bispecific antibody designed to deplete CD79b+ B cells. 

• Protuoso Biosciences – Protuoso raised $9.5M in seed financing to build its hub-and-spoke platform for multifunctional Muxbodies, fully recombinant fusion proteins designed to support next-generation antibody development. 

• Infex Therapeutics – Infex secured £4.3M in funding to advance its anti-infective pipeline targeting drug-resistant infections, including RESP-X, a monoclonal antibody program.