BioInvent Announces Publication of Preclinical Manuscript on BI-1808 and BI-1910 in Cancer Research

• Preclinical manuscript that characterizes the mechanism of action, broad antitumor efficacy, and immune-activating properties of BI-1808 and BI-1910 across diverse tumor microenvironments

• Data demonstrates the ability of the lead anti-TNFR2 antibody BI-1808 to elicit antitumor immunity in CD8+ T cell poorly infiltrated tumors resistant to immune checkpoint blockade

• BI-1808 is currently being evaluated in ongoing Phase 2a clinical trials with clinical data showing promising activity across both hematologic and solid tumor settings with the potential to become the next standard of care in ovarian cancer

Lund, Sweden – August 20, 2026 – BioInvent International AB (“BioInvent”) (Nasdaq Stockholm: BINV), a leader in the discovery of novel immune-modulatory antibodies, today announced that a preclinical manuscript characterizing the mechanism of action, broad antitumor efficacy, and ability to elicit antitumor immunity of BI-1808 and BI-1910 has been published in Cancer Research, a peer-reviewed journal of the American Association for Cancer Research. The publication is entitled "Ligand-Blocking and Agonist Antibodies Targeting TNFR2 Employ Distinct Modes of Action to Induce Antitumor Immunity" and is available at https://doi.org/10.1158/0008-5472.CAN-26-0274.

"This publication provides a comprehensive mechanistic understanding of how BI-1808 and BI-1910 modulate the tumor microenvironment to drive antitumor immunity. It also highlights BioInvent’s leading role in TNFR2 targeting," said Björn Frendéus, Ph.D., Chief Scientific Officer of BioInvent. "The breadth of activity demonstrated across tumor types, notably including poorly CD8+ T cell infiltrated tumors resistant to immune checkpoint blockade, in these preclinical studies is consistent with the clinical signals we are observing with BI-1808 and reinforces our conviction in TNFR2 as a high-value target in cancer immunotherapy."

Both anti-TNFR antibodies show potent anti-tumor efficacy across multiple syngeneic tumor models in vivo, can effectively be combined with anti-PD-1, and trigger CD8+ T cell antitumor immunity, albeit by different mechanisms; BI-1808 is a ligand-blocking FcgR-engaging antibody that depletes immunosuppressive Treg cells and reprograms myeloid cells. BI-1910, currently paused due to priority reasons, is a pure agonist antibody that directly co-stimulates T and NK cells through partially FcgR-independent mechanisms.

About BI-1808 
BI-1808 is a first-in-class drug candidate targeting TNFR2. TNFR2 is upregulated on both immunosuppressive and inflammatory tumor-infiltrating lymphocytes (TILs) and on myeloid cells in the tumor microenvironment, making it a dynamic, promising new target for cancer immunotherapy. BI-1808 is in clinical development for the treatment of T-cell lymphoma and solid tumors. In an ongoing Phase 1/2a study, it has shown both single-agent activity and excellent tolerability, as well as efficacy and a favorable safety profile in combination with pembrolizumab, in solid tumors and T-cell lymphomas

About BioInvent
BioInvent International AB (Nasdaq Stockholm: BINV) is a clinical-stage biotech company that discovers and develops novel and first-in-class immunomodulatory antibodies for cancer therapy, with drug candidates in ongoing clinical programs in Phase 1/2 trials for the treatment of hematological cancer and solid tumors. The Company's validated, proprietary n-CoDeR F.I.R.S.T™ technology platform identifies both targets and the antibodies that bind to them, generating many promising new immune-modulatory candidates to fuel the Company's own clinical development pipeline and providing licensing and partnering opportunities.

The Company generates revenues from research collaborations and license agreements with multiple top-tier pharmaceutical companies, as well as from producing antibodies for third parties in the Company's fully integrated manufacturing unit. More information is available at www.bioinvent.com.

For further information, please contact:
Cecilia Hofvander, VP Investor Relations
Phone: +46 (0)46 286 85 50
Email: cecilia.hofvander@bioinvent.com

BioInvent International AB (publ)
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www.bioinvent.com

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