BioInvent's BI-1808 Shows 46% Response Rate in Cutaneous T-Cell Lymphoma Phase 2a Trial
核心洞察
BioInvent (搜索)'s first-in-class anti-TNFR2 (搜索) antibody BI-1808 demonstrated a 46% objective response rate and 92% disease control rate in relapsed/refractory cutaneous T-cell lymphoma (搜索) patients.
The Phase 2a monotherapy trial showed robust immune activation with CD8+ T-cell infiltration and elevated granzyme B levels in skin biopsies at 5 weeks.
BI-1808 received FDA Fast Track Designation and Orphan Drug Designation for T-cell lymphoma (搜索) treatment, positioning it for accelerated development in this rare cancer indication.
BioInvent International (搜索) announced promising Phase 2a monotherapy results for BI-1808, a first-in-class anti-TNFR2 (搜索) antibody, in cutaneous T-cell lymphoma (搜索) (CTCL (搜索)) at the 2025 American Society of Hematology Annual Meeting. The trial demonstrated a 46% objective response rate (6 of 13 evaluable patients) and a 92% disease control rate (12 of 13) in relapsed/refractory CTCL patients.
Strong Clinical Activity in Rare Cancer
The signal-seeking monotherapy portion of the ongoing Phase 2a trial (NCT04752826) enrolled 21 patients with T-cell lymphomas, including 14 CTCL (搜索) patients (13 evaluable for efficacy) and 2 peripheral T-cell lymphoma (搜索) (PTCL (搜索)) patients. Among the 13 evaluable CTCL patients, one Sézary syndrome (搜索) patient achieved complete response, five patients (four mycosis fungoides (搜索), one Sézary syndrome) showed partial response, six patients had stable disease, and only one mycosis fungoides patient experienced progressive disease.
"We're excited by the emerging clinical profile of BI-1808 in T-cell lymphomas, especially CTCL (搜索) where treatment options are scarce," said Martin Welschof, Chief Executive Officer of BioInvent (搜索). "The strong disease control rate and immune activation validate TNFR2 (搜索) as a powerful dual-action target-reducing regulatory T cells while boosting effector function."
Immune Activation Biomarkers
The study provided evidence of robust immune engagement through skin biopsy analysis. At 5 weeks, researchers observed significant CD8+ T-cell infiltration accompanied by elevated granzyme B levels, indicating cytotoxic immune activation. Disease "flares" characterized by increased skin peeling, erythema, and pruritis were observed during the first weeks of treatment in several cases, considered related to immune activation associated with depletion of regulatory T cells and influx of CD8+ T cells.
Favorable Safety Profile
As of October 6, 2025, all 21 patients with T-cell lymphomas received BI-1808 as a 1000 mg single agent every 3 weeks. All treatment-related adverse events were classified as mild or moderate with no potentially related Grade 3 or higher adverse events reported. The monotherapy part of the study has proceeded to the dose optimization phase, which will inform the design of future pivotal trials.
Regulatory Milestones and Development Strategy
BI-1808 has received significant regulatory support for its development. In April 2025, the drug was granted Fast Track Designation for CTCL (搜索) treatment from the U.S. Food and Drug Administration, and Orphan Drug Designation was received in March 2025 for T-cell lymphoma (搜索) treatment. In November 2025, a positive opinion was received from the European Medicines Agency regarding Orphan Drug Designation for BI-1808 in CTCL.
BioInvent (搜索) is currently evaluating BI-1808 in combination with pembrolizumab in a separate cohort for solid tumors. The safety and preliminary efficacy of both monotherapy and combination approaches are being assessed in sub-cohorts of the ongoing Phase 2a study, which will form the basis for selecting the optimal approach for the subsequent pivotal Phase 2 study.
Addressing Unmet Medical Need
T-cell lymphomas make up about 10-15% of all Non-Hodgkin's lymphomas, with CTCL (搜索) and PTCL (搜索) being the main types. CTCL originates in the skin and includes mycosis fungoides (搜索) and Sézary syndrome (搜索), while PTCLs are nodal or systemic T-cell lymphomas. Survival is poor in PTCL, advanced mycosis fungoides, and Sézary syndrome, with a 5-year survival range of 20-60%.
The anti-TNFR2 (搜索) antibody BI-1808 is part of BioInvent (搜索)'s tumor-associated regulatory T cells targeting program. TNFR2 is particularly upregulated on regulatory T cells of the tumor microenvironment and has been shown to be important for tumor expansion and survival, representing a new and promising target for cancer immunotherapy.