Biohaven Unveils Early Phase 1 BHV-1530 Data and Regeneron Partnership

Biohaven will present updated Phase 1 clinical data for BHV-1530, its investigational FGFR3-directed antibody-drug conjugate (ADC), at the European Society for Medical Oncology (ESMO) Congress 2026. The findings, scheduled for presentation as Abstract 1019P during the meeting in Madrid, Spain (October 23–27), will provide an updated assessment of the therapy’s preliminary efficacy and safety in patients with advanced solid tumors. Biohaven also announced a clinical supply agreement with Regeneron Pharmaceuticals to evaluate BHV-1530 in combination with the PD-1 inhibitor cemiplimab (Libtayo).

BHV-1530 Broadens the Potential of FGFR3-Targeted Therapy

BHV-1530 is the first FGFR3-directed ADC to enter clinical development. It combines an antibody targeting FGFR3 with Biohaven’s proprietary topoisomerase I (TopoIx) payload. Unlike approved FGFR tyrosine kinase inhibitors (TKIs), which are generally limited to tumors with activating FGFR3 alterations, BHV-1530 targets FGFR3-expressing tumor cells regardless of alteration status, including tumors with wild-type FGFR3 overexpression.

FGFR3 is an established therapeutic target in urothelial cancer and several other solid tumors. By delivering a cytotoxic payload directly to FGFR3-expressing cells rather than continuously inhibiting receptor signaling, BHV-1530 may avoid some toxicities associated with currently available FGFR inhibitors.

Phase 1 Trial Shows Early Antitumor Activity

BHV-1530 is being evaluated in the ongoing first-in-human Phase 1 BHV1530-101 trial (NCT06874335), an open-label, multicenter study enrolling adults with advanced or metastatic solid tumors whose disease has progressed after, or is intolerant of, standard therapy. The study does not require enrollment based on FGFR3 alteration status and is assessing safety, pharmacokinetics, recommended dose, and preliminary antitumor activity.

The ESMO presentation will build on findings first reported during Biohaven’s R&D Day in May 2026, which showed early tumor reductions in patients with both FGFR3-altered tumors and tumors with wild-type FGFR3 overexpression across multiple cancer types.

Among the notable cases was a patient with FGFR3-TACC3 fusion-positive metastatic urothelial cancer who experienced tumor response after progressing on four prior lines of therapy, including enfortumab vedotin (Padcev), pembrolizumab, and two FGFR-targeted small molecules. Biohaven also reported confirmed partial responses in heavily pretreated patients across multiple tumor types, although detailed response rates have not yet been disclosed.

Favorable Safety Profile Supports Further Development

Preliminary safety findings showed BHV-1530 was generally well tolerated across the evaluated dose levels. Investigators reported no dose-limiting toxicities or FGFR inhibitor class toxicities, including hyperphosphatemia, nail disorders, stomatitis, and retinopathy, adverse events that commonly limit treatment with approved FGFR TKIs.

Biohaven said these findings suggest a potentially broader therapeutic index than existing FGFR inhibitors, although confirmation in larger clinical studies will be required. If supported by future data, BHV-1530 could extend FGFR3-targeted therapy beyond patients with genomic alterations to those with tumors expressing wild-type FGFR3.

Regeneron Collaboration Expands Combination Strategy

Biohaven has entered a clinical supply agreement with Regeneron Pharmaceuticals to evaluate BHV-1530 in combination with cemiplimab (Libtayo) in patients with advanced solid tumors. The collaboration is supported by preclinical evidence indicating that the ADC’s TopoIx payload induces immunogenic cell death and may enhance the activity of immune checkpoint inhibition.

The agreement expands an existing collaboration between the companies involving BHV-1510, Biohaven’s investigational TROP2-directed ADC, which is also being studied with cemiplimab. Early findings from that program have shown responses in patients previously treated with PD-(L)1 inhibitors, supporting broader evaluation of Biohaven’s ADC platform in combination with immunotherapy.

Path Forward

Additional efficacy, safety, pharmacokinetic, and dose-optimization data from the ongoing Phase 1 study will be presented at the ESMO Congress 2026. Biohaven also plans to initiate combination cohorts evaluating BHV-1530 with cemiplimab during the second half of 2026 as development continues in advanced solid tumors.

References

Biohaven to Present New Clinical Data at ESMO Congress on BHV-1530, a Novel FGFR3-Directed ADC With a Proprietary Topoisomerase I (TopoIx) Payload | Biohaven, Ltd.