This is a first-in-human, Phase 1, non-randomized, multicenter, open-label clinical study designed to investigate the safety, tolerability, dosimetry, biodistribution, and pharmacokinetics (PK) of [225Ac]-FPI-2068, [111In]-FPI-2107, and FPI-2053 in metastatic and/or recurrent solid tumors (HNSCC, NSCLC, mCRC, PDAC, GC, RCC).

The study will be conducted in 2 parts:

Part A: optimization of the FPI-2053 dose (treatment with dose level 1 of [225Ac]-FPI-2068 - fixed dose).

Part B: dose escalation of [225Ac]-FPI-2068 with optimal FPI-2053. Part B will commence once the optimal dose of FPI-2053 is determined in Part A. The RP2D will be determined from Part B based on all available safety, efficacy, PK, and dosimetry information.

Key Inclusion Criteria:

Histologically and/or cytologically confirmed solid tumor that is metastatic, locally advanced, recurrent or inoperable.

Disease that has progressed despite prior treatment, and for which additional effective standard therapy is not available or is contraindicated, not tolerable, or the participant refuses standard therapy.

Measurable disease as defined by RECIST Version 1.1

ECOG Performance status of 0 or 1

Adequate organ function

Key Exclusion Criteria:

Previous treatment with any systemic radiopharmaceutical

Prior anti-cancer therapy unless adequate washout and recovery from toxicities

Contraindications to or inability to perform the imaging procedures required in this study

Radiation therapy (RT) within 28 days prior to the first dose of [111In]-FPI-2107

Uncontrolled pleural effusion, pericardial effusion, or ascites requiring recurrent drainage procedures (≥ once per month)

Patients with known CNS metastatic disease unless treated and stable

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org. Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.