A Study of ImmunoPet Imaging Using 89Zr-DFO-REGN5054 in Adult Participants With Solid Cancers Treated With Cemiplimab

• Status: Not yet recruiting
• Trial end date: 2026-02-10
• Target enrollment: 0
• Participant gender: All

Summary

The primary objective of the study is to determine the safety and tolerability of 89Zr-DFO-REGN5054 alone and in combination with cemiplimab.

The secondary objectives include:

For Part A:

• To characterize the radioactivity pharmacokinetic (PK) profile of 89Zr-DFO-REGN5054

• To establish an adequate mass dose and activity dose of 89Zr-DFO-REGN5054 and optimal post-infusion time for imaging

For Parts A and B:

• To evaluate the association of CD8 expression in tissue biopsies [via immunohistochemistry (IHC)] with tumor 89Zr˗DFO˗REGN5054 uptake in vivo [via positron emission tomography (PET)] and ex vivo (via autoradiography)

• To evaluate the uptake of 89Zr˗DFO˗REGN5054 in tumors, normal CD8-expressing tissues, and blood

• Phase: Phase 1
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: Regeneron Pharmaceuticals
• Treatments: Cemiplimab

Criteria

Key Inclusion Criteria:

• Advanced or metastatic solid tumors that may respond to anti-programmed cell death protein 1 (PD-1) immunotherapy

• Measurable disease according to Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 criteria

• Eastern Cooperative Oncology Group (ECOG) performance status of ≤1

• Adequate organ and bone marrow function as defined in the protocol

• Willing and able to comply with clinic visits and study-related procedures (including required tumor biopsy for Part B)

Key Exclusion Criteria:

• Currently receiving another cancer treatment or inadequate time since last therapy, as defined in the protocol

• Has not yet recovered from acute toxicities from prior therapy; exceptions defined in the protocol

• Prior treatment with a blocker of the PD-1/Programmed death ligand 1 (PD-L1) pathway

• Currently receiving or has received chimeric antigen receptor (CAR-T) cell therapy

• Symptomatic or untreated brain metastases, leptomeningeal disease, or spinal cord compression

• Known history of or any evidence of interstitial lung disease, active, noninfectious pneumonitis (past 5 years) or active tuberculosis

NOTE: Other protocol defined inclusion/exclusion criteria apply.