Dostarlimab Has ‘Impactful’ PFS Benefit in dMMR Advanced Endometrial Cancer

Dostarlimab-gxly (Jemperli) is a “powerful addition” to first-line chemotherapy in the treatment of patients with advanced or recurrent endometrial cancer, especially among those with mismatch repair deficient (dMMR) disease, according to Ritu Salani, MD.

CancerNetwork^® spoke with Salani, the Gynecologic Oncology Fellowship Director at University of California Los Angeles Health and a Gynecologic Oncology editorial board member for the journal ONCOLOGY^®, about data from the phase 3 ENGOT-EN6-NSGO/GOG-3031/RUBY trial (NCT03981796) presented at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting. In particular, she detailed the progression-free survival (PFS) benefit of dostarlimab plus chemotherapy in this patient population vs chemotherapy alone.

Salani also described how concordance between the blinded independent central review (BICR) and investigator assessments affirm the results of the RUBY trial and the role of dostarlimab in the treatment of advanced or recurrent endometrial cancer.

Transcript:

This is one of the most exciting abstracts that we've seen this year. Just to put it in context, the RUBY trial looked at the addition of dostarlimab to chemotherapy, with the maintenance dostarlimab for 3 years vs just chemotherapy alone. This looked at an intent-to-treat population, and then focused on the dMMR [cohort] as the first primary outcome. We saw PFS significantly improve in this population with a 61.4% PFS rate at 2 years vs 15.7% in the placebo arm. [It is a] really impactful difference in the dMMR population. [There was not] as striking of a result in the proficient population, but [there was] still a notable improvement in PFS rate with 36.1% vs 18.1% in the placebo arm.

The BICR analysis is important is [because] it takes out clinician biases. The BICR for radiology looks at the imaging and really details progression, stable disease, or even response by someone who has no input into what the patient is receiving or how the patient is doing.

There are always some differences. There are some biases: we want to keep patients on trial who can if they're doing well. There's also clinical progression that the provider can see but is not detailed on the radiographic imaging. What's really important is it confirms the study results. And so, the BICR analysis presented this year at ASCO showed that there was a high concordance between the blinded independent review as well as a provider-assessed response. And this just continues to add to the confirmatory results of this trial. [Dostarlimab] is a powerful addition to frontline chemotherapy for these patients.

Reference

Powell MA, Hietanen S, Coleman RL, et al. Dostarlimab for primary advanced or recurrent (A/R) endometrial cancer (EC): outcomes by blinded independent central review (BICR) of the RUBY trial (ENGOT-EN6-NSGO/GOG-3031/RUBY). J Clin Oncol. 2023;41(suppl 16):5503. 10.1200/JCO.2023.41.16_suppl.5503