Ubamatamab, Anti-PD-1 ICI, May Bolster Immune Response in Kidney Cancer

Ubamatamab in combination with anti–PD-1 inhibition may enhance the immune response in patients with MUC16-expressing SMARCB1-deficient renal medullary carcinoma and epithelioid sarcoma, said Pavlos Msaouel, MD, PhD.

CancerNetwork® spoke with Msaouel, an assistant professor at the Department of Genitourinary Medical Oncology, and an assistant professor in the Department of Translational and Molecular Pathology at the University of Texas MD Anderson Cancer Center, during the 2024 Kidney Cancer Research Symposium about the clinical and preclinical implications of ubamatamab monotherapy and in combination with an anti-PD-1 inhibitor.

Additionally, Msaouel outlined steps that will be undertaken in a phase 2 trial assessing the experimental therapy in patients with both cancer types. He said the trial will initially aim to evaluate the clinical effects of ubamatamab alone and follow up with a similar evaluation for ubamatamab in combination with an anti-PD-1 inhibitor, specifically cemiplimab (Libtayo).

The phase 2 study trial will enroll up to 20 patients in each disease cohort, patients with stage I will receive ubamatamab monotherapy, and those with stage II will receive ubamatamab combined with cemiplimab. Patients with stage I disease who have progression will be given the option to enroll in the second stage.

The coprimary end points of the study were objective response rate (ORR) and disease control rate (DCR). Secondary end points included overall survival (OS), progression-free survival (PFS), duration of response (DOR), and safety. End points will be analyzed separately for each disease cohort and stage.

The regimens are considered promising by investigators if ORR or DCR is greater than 15% or greater than 26% for patients with epithelioid sarcoma Additionally, to identify changes in immune cell subsets, correlative analyses both pre- and post-treatment will be performed in blood and tumor biopsy tissues.

Transcript:

There is evidence, both preclinical and clinical, that when in addition to using ubamatamab, we combine it with an anti-PD-1 immune checkpoint inhibitor like cemiplimab that might enhance the immune response even further. What our trial will do in each of [renal meduallary carcinoma and epitheliod sarcoma] is test initially what ubamatamab does alone, what its effects [are] both clinically and in tumor tissues and blood samples, and then also test what happens when we give ubamatamab in combination with anti-PD-1 inhibition with cemiplimab.

Reference

Msaouel P. Phase II trial of ubamatamab in MUC16-Expressing SMARCB1-deficient renal medullary carcinoma and epithelioid sarcoma. Presented at: 2024 Kidney Cancer Research Summit; July 11-12, 2024; Boston, Massachusetts.