MARSEILLE, France, July 21, 2026
Innate Pharma has announced the successful completion of enrollment in the dose-escalation portion of the Phase 1 IPH4502-101 clinical trial, marking an important milestone in the development of its proprietary Nectin-4 exatecan antibody-drug conjugate (ADC) for the treatment of advanced solid tumors. The study has enrolled 76 patients across clinical sites in France and the United States, with a preliminary clinical data readout expected by the end of 2026. Early findings indicate a favorable safety profile, including limited hematological toxicity, while objective tumor responses have been observed in heavily pre-treated patients with urothelial carcinoma (UC), non-small cell lung cancer (NSCLC), and head and neck squamous cell carcinoma (HNSCC). These encouraging results reinforce the potential of IPH4502 as a differentiated next-generation ADC designed to address significant unmet needs in patients with treatment-resistant cancers.
Phase 1 Study Advances Toward Dose Optimization
The ongoing IPH4502-101 Phase 1 trial is an open-label, multicenter clinical study evaluating the safety, tolerability, pharmacology, and preliminary anti-tumor activity of IPH4502 as a single-agent therapy in patients with advanced Nectin-4-expressing solid tumors. Eligible cancer types include urothelial carcinoma, NSCLC, HNSCC, breast, ovarian, gastric, esophageal, and colorectal cancers. Completion of the dose-escalation stage provides researchers with valuable clinical information that will guide dose optimization and future expansion cohorts. According to Innate Pharma, preliminary data from all 76 enrolled patients are expected before year-end and will support decisions regarding the optimal therapeutic dose and target tumor populations for continued clinical development. This milestone represents an important step toward establishing the clinical profile of IPH4502 across multiple difficult-to-treat malignancies.
Differentiated ADC Design Demonstrates Early Clinical Promise
IPH4502 has been engineered using three proprietary components that distinguish it from currently available antibody-drug conjugates. The investigational therapy combines a humanized anti-Nectin-4 antibody, a stable proprietary linker, and exatecan, a potent topoisomerase I inhibitor designed to overcome limitations associated with earlier MMAE-based ADCs, including resistance mediated by multidrug resistance protein 1 (MDR1). The company’s proprietary linker enables a controlled release of free exatecan, which may contribute to the limited hematological toxicity observed during dose escalation while maintaining anti-tumor activity. Early clinical findings have demonstrated objective responses in patients previously treated with enfortumab vedotin for urothelial carcinoma, as well as encouraging activity in NSCLC and HNSCC, suggesting that IPH4502 may retain efficacy even in treatment-resistant disease settings.
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Expanding Opportunities in Solid Tumor Therapy
Preclinical research has demonstrated that IPH4502 retains anti-tumor activity in enfortumab vedotin-resistant tumor models and in cancers with low or heterogeneous Nectin-4 expression, indicating the potential to expand treatment beyond traditional urothelial carcinoma indications. These characteristics position the investigational ADC as a promising candidate for a broad range of solid tumors with high unmet medical need. With enrollment in the dose-escalation phase now complete and dose optimization approaching, Innate Pharma expects the upcoming clinical dataset to further define the therapeutic potential of IPH4502 while supporting future clinical development strategies. As the field of antibody-drug conjugates continues to evolve rapidly, differentiated platforms capable of combining improved safety with durable anti-tumor efficacy remain a major focus of oncology innovation, placing IPH4502 among the promising next-generation ADC candidates advancing through early-stage clinical development.
Source: Innate Pharma Press release
