This is a first-in-human, open-label, multicenter, Phase 1 study to evaluate the safety, tolerability and preliminary efficacy of IPH4502 and to determine the recommended Phase 2 dose (RP2D) in advanced solid tumors that are known to express Nectin-4

This is a first-in-human, open-label, multicenter, single-arm Phase 1 study, with a part 1 dose escalation guided by a Bayesian optimal interval design with backfilling (BOIN-BF), followed by a part 2 dose optimization in up to 2 selected indications. This study is to measure the safety, tolerability, pharmacokinetics, and preliminary efficacy of escalating doses of IPH4502 in patients with advanced solid tumors that are known to express Nectin-4.

Main Inclusion Criteria:

• Histologically confirmed, unresectable, locally advanced or metastatic solid tumors that are known to express Nectin-4
• Prior systemic treatment for locally advanced or metastatic disease, yet no therapy with demonstrated clinical benefit for the tumor type is available.
• Measurable disease according to RECIST 1.1.
• Archival tumor tissue obtained within 4 months of screening and since the last anticancer therapy prior to the study or agree to undergo a tumor biopsy at baseline.
• Adequate organ function and hematological function.

Main Exclusion Criteria:

• Known or suspected brain metastases.
• Participants with an active infection, Any other infection requiring systemic treatment or latent infection.
• Participants with clinically significant comorbidity(s).
• History of treatment for, or suspicion or confirmed interstitial lung disease (ILD) at baseline.
• Condition being treated with systemic corticosteroids or immunosuppressive therapy during IPH4502 treatment.
• Thromboembolic event requiring anticoagulation therapy ≤14 days prior to the first dose of IPH4502.
• Clinically significant cardiovascular disease and/or cardiac repolarization abnormality.
• Participants with symptomatic heart failure, Acute coronary syndromes
• Participant is receiving or has received anticancer therapy prior to enrolment that may have impact on the assessment of IPH4502.
• Major surgery ≤28 days and minor surgery ≤7 days prior to first dose of IPH4502 or 6 months for coronary artery bypass surgery.
• Concomitant medications or vaccines : Live-attenuated vaccines ≤ 6 weeks prior to first dose of IPH4502; systemic corticosteroids or other immunosuppressive agents within 14 days prior to the first dose of IPH4502; systemic use of moderate or strong CYP 3A4 inhibitors; systemic use of moderate or strong CYP 3A4 inducers.