The goal of this clinical trial is to evaluate the safety, tolerability and anti-tumor activity of IMA402 in patients with recurrent and/or refractory solid tumors.

Primary objectives:

• To determine the maximum tolerated doses and/or recommended doses for extensions for IMA402 as monotherapy and in combination with pembrolizumab (Phase Ia)
• To characterize the safety and tolerability of IMA402 as monotherapy and in combination (Phase I/II)
• To evaluate anti-tumor activity of IMA402 as monotherapy and in combination (Phase II)

Secondary objectives:

• To evaluate the initial anti-tumor activity of IMA402 as monotherapy and in combination (Phase I)
• To evaluate anti-tumor activity of IMA402 as monotherapy and in combination (Phase II)
• To describe the PK of IMA402 as monotherapy and in combination (Phase I/II)

The study will be conducted in two phases:

• Phase Ia: Dose escalation/de-escalation
• Phase Ib: Dose extension
• Phase II: Dose extension in selected Indication-specific extension cohort(s) (ISEC)

Inclusion Criteria:

• Patients ≥ 18 years old
• Patients must have a specific pathologically confirmed and documented advanced and/or metastatic solid tumor indication
• Patients must have received or not be eligible for indicated standard-of-care treatments per cohort
• Measurable disease according to RECIST 1.1
• Confirmed HLA status
• ECOG Performance Status of 0 to 1
• Adequate baseline hematologic, hepatic and renal function, acceptable coagulation status

Exclusion Criteria:

• Other active malignancies that require treatment or that might interfere with the trial endpoints
• The patient is pregnant or is breastfeeding
• History of hypersensitivity to components of IMA402 or rescue medications; hypersensitivity to or contraindication according to current SmPC for respective combination medicinal product
• The patient has concurrent severe and/or uncontrolled medical disease. Any other health condition that would, in the investigator's or sponsor's judgement, contraindicate the patient's participation in the clinical trial because of safety concerns or compliance with clinical trial procedures
• Patients with active brain metastases, history of bleeding into brain metastases, known brain metastases who are receiving therapeutic anticoagulation

There is not a plan to make IPD available.