Sweden-based BioInvent International AB (Nasdaq Stockholm: BINV) announced receipt of US FDA Fast Track Designation for BI-1808, a first-in-class anti-tumor necrosis factor receptor 2 (TNFR2) monoclonal antibody, for the treatment of ovarian cancer in combination with pembrolizumab (Keytruda). The designation, granted August 7, 2026, applies to the combination regimen in platinum-resistant ovarian cancer (PROC) and is supported by Phase 2a interim data presented at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting.
The ASCO data, drawn from 25 evaluable patients in the combination arm of NCT04752826 with a data cut-off of April 20, 2026, reported a 24% confirmed overall response rate (ORR) and a 56% disease control rate (DCR) with BI-1808 plus pembrolizumab, without a chemotherapy backbone. Preliminary median progression-free survival (mPFS) was 10.3 months, with several responses ongoing beyond 10 months. No formal p-values were disclosed. BioInvent attributed the activity to BI-1808's mechanism of depleting immunosuppressive regulatory T cells (Tregs) and reprogramming myeloid cells in the tumor microenvironment, complementing PD-1 blockade by pembrolizumab. The company said the treatment was generally well-tolerated, though specific Grade ≥3 rates were not disclosed in public materials.
The 24% ORR compares with the approximately 8% response rate historically reported for pembrolizumab monotherapy in PROC. In February 2026, the FDA approved pembrolizumab in combination with paclitaxel — with or without bevacizumab — for platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal carcinoma, establishing a chemotherapy-based combination as a reference point in this setting. BioInvent's chemotherapy-free approach targets a distinct mechanistic axis.
BI-1808 has accumulated prior regulatory recognition in other indications: the FDA granted Fast Track Designation for CTCL in April 2025, and the European Medicines Agency (EMA) Committee for Orphan Medicinal Products issued a positive opinion for Orphan Drug Designation in cutaneous T-cell lymphoma (CTCL) in November 2025. The ovarian cancer designation is the first for BI-1808 in a solid tumor indication under a combination regimen.