A Study to Assess Safety, Tolerability and Imaging Characteristics of [68Ga]Ga-DPI-4452 and to Assess Safety, Tolerability, and Efficacy of [177Lu]Lu-DPI-4452 in Participants With Unresectable Locally Advanced or Metastatic Solid Tumors

The main purpose of Part A of the study is to evaluate safety, tolerability and tracer uptake after a single intravenous (IV) administration of [68Ga]Ga-DPI-4452; Part B: is to determine the recommended phase 2 dose (RP2D) [maximum tolerated dose (MTD) or lower dose] for [177Lu]Lu-DPI-4452 for each tumor type; Part C: is to evaluate the preliminary antitumor activity of [177Lu]Lu-DPI-4452 as monotherapy.

Inclusion Criteria:Part A, B and C:Written informed consent, dated and signed by the patient prior to any study-specific procedureHas histologically confirmed, unresectable locally advanced or metastatic clear cell renal cell cancer (ccRCC), pancreatic ductal adenocarcinoma (PDAC) or colorectal cancer, (CRC).Participants with CRC or PDAC: availability of fresh biopsy, OR an archival biopsy/surgical specimen of the tumor (preferably, taken after last prior line of therapy).Presence of at least 1 non-irradiated tumor lesion detected at conventional imaging (CT/MRI) documented within 4 weeks prior to the [68Ga]Ga-DPI-4452 administration.Measurable disease per response evaluation criteria in solid tumors (RECIST) v1.1Exclusion Criteria:Any major surgery within 12 weeks before enrollmentInability to stay in the scanner bed with the arms resting out of the thoracic and abdominal fields (i.e., arms alongside the body or raised arm position) for the duration of the scanPart A:Has known hypersensitivity to the active substance, to any of the excipients of the DPI-4452, or to radiographic contrast agents.Bladder outflow obstruction or unmanageable urinary incontinence.Participants who have not had resolution of clinically significant toxic effects of prior systemic cancer therapy, surgery, or radiotherapy to Grade ≤1 (except for laboratory parameters specified above, Grade 2 alopecia, and/or stable Grade 2 sensory neuropathy, according to National Cancer Institute Common Terminology Criteria for Adverse Events [NCI-CTCAE]).Administration of a radiopharmaceutical within a period corresponding to 10 half-lives of the radionuclide used prior to injection of [68Ga]Ga-DPI-4452.Previous Carbonic anhydrase (CA) IX-targeting treatment.Prior external beam radiation therapy (EBRT) to more than 25% of the bone marrow, as judged by the Investigator.Part B and Part C:Known hypersensitivity to the active substance, to any of the excipients of the DPI-4452, or to radiographic contrast agents.Bladder outflow obstruction or unmanageable urinary incontinence.Participants who have not had resolution of clinically significant toxic effects of prior systemic cancer therapy, surgery, or radiotherapy to Grade ≤1 (except for laboratory parameters specified above, Grade 2 alopecia, or stable Grade 2 sensory neuropathy, according to NCI-CTCAE).Administration of a radiopharmaceutical with therapeutic intent within a period of 6 months prior to injection of [68Ga]Ga-DPI-4452.Any previous CA IX-targeting treatment for more than 1 cycle or 1 month.Participants who received any systemic antineoplastic therapy for the underlying disease and/or other investigational agents within a period which is ≤5 half-lives or ≤4 weeks (whichever is shorter).Note: Other inclusion/exclusion criteria mentioned in the protocol may apply.