The U.S. Food and Drug Administration (FDA) approved Roche’s VENTANA MMR RxDx Panel for advanced or recurrent endometrial cancer as a companion test to identify patients likely to benefit from treatment with anti-PD1 immunotherapy JEMPERLI (dostarlimab-gxly) from GlaxoSmithKline, which also received the agency’s approval.
Roche said the collaboration between the two companies “represents an important step towards a personalized healthcare strategy that can help identify patients who are most likely to benefit from a specific therapy.”
Endometrial cancer is the most common gynecologic cancer in the U.S. and the fourth most common cancer in women in North America. In addition, about 90,000 women globally die from endometrial cancer each year. There are limited treatment options for women whose disease progresses on or after first-line therapy and this is the first companion diagnostic to identify endometrial cancer patients eligible for anti-PD1 immunotherapy.
Roche said MMR deficiency is most common in endometrial cancer. This companion diagnostic (CDx) provides clinicians with a standardized testing option that uses a comprehensive panel of DNA mismatch repair (MMR) biomarkers tested by immunohistochemistry (IHC).
The VENTANA MMR RxDx Panel is a label expansion of Roche’s current on-market VENTANA MMR IHC Panel. VENTANA MMR RxDx Panel is a qualitative immunohistochemistry test intended for use in the assessment of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2 and MSH6) in formalin-fixed, paraffin-embedded (FFPE) endometrial carcinoma tissue by light microscopy.
The OptiView DAB IHC Detection Kit is used for MLH1, MSH2 and MSH6, and the OptiView DAB IHC Detection Kit with the OptiView Amplification Kit is used for PMS2 on a VENTANA BenchMark ULTRA instrument.
DNA mismatch repair (MMR) proteins have been clinically proven to be predictive biomarkers for PD-1 targeted therapy; specifically, a loss of expression of one or more MMR proteins might predict an increased likelihood of response to such therapy.3,4,5 PD-1 inhibitors can be effective in cancers with a high frequency of MMR deficiency and/or microsatellite-instability, high (MSI-H) including endometrial cancer.3,5 MMR is a conserved molecular mechanism that functions to correct the improper base substitutions that spontaneously occur during DNA replication. Defects in the MMR machinery have been attributed to mutations in the MMR proteins.
As far as the treatment, Jemperli works by targeting the cellular pathway known as PD-1/PD-L1 (proteins found on the body’s immune cells and some cancer cells). Jemperli helps the body’s immune system in its fight against cancer cells by blocking this pathway.
The safety and efficacy of Jemperli was studied in a single-arm, multi-cohort clinical trial. Of the 71 patients with dMMR recurrent or advanced endometrial cancer who received Jemperli in the trial, 42.3% had a complete response (disappearance of tumor) or a partial response (shrinkage of tumor) to treatment with Jemperli. For 93% of responders, the response lasted for six months or more.
