Health Canada expands Jemperli (dostarlimab for injection) plus chemotherapy approval to all adult patients with primary advanced or first recurrent endometrial cancer, as the first and only immun...

• Building on the last approval of Jemperli offering PFS benefit in dMMR/MSI-HC endometrial cancer, the expanded indication now offers survival benefit across the overall study population (dMMR/MSI-H and MMRp/MSS tumours)
• Approval based on RUBY Part 1 trial, where Jemperli plus chemotherapy demonstrated a statistically significant and clinically meaningful 31% reduction in risk of death versus chemotherapy alone

MISSISSAUGA, ON, April 17, 2025 /CNW/ - GSK today announced that Health Canada has approved Jemperli (dostarlimab for injection) in combination with chemotherapy (carboplatin and paclitaxel) for the treatment of adult patients with primary advanced or first recurrent endometrial cancer who are candidates for systemic therapy.^[1] This approval broadens the previous indication for Jemperli in combination with carboplatin and paclitaxel to include patients with mismatch repair proficient (MMRp)/microsatellite stable (MSS) tumours, which represents approximately 75% ^[2] of patients diagnosed with endometrial cancer and who have limited treatment options.

"Today's expanded approval of Jemperli for all patients with primary advanced or first recurrent endometrial cancer in Canada is supported by an overall survival benefit across the study population. This represents a significant milestone and demonstrates Jemperli's potential to redefine the treatment of cancers with high mortality rates and unmet needs, such as endometrial cancer," said Michelle Horn, Country Medical Director at GSK Canada. "Jemperli remains a backbone of our immuno-oncology program, offering renewed hope to Canadian patients and emphasizing GSK's dedication, as a research-focused company, to addressing the most common gynaecologic cancer in Canada."

Health Canada's approval to expand the use of Jemperli is based on results from Part 1 of the RUBY phase III trial. RUBY Part 1 met its dual primary endpoints of Progression-Free Survival (PFS) and Overall Survival (OS) in the overall population of patients with primary advanced or recurrent endometrial cancer, and is the only clinical trial in this setting to show a clinically meaningful and statistically significant OS benefit, demonstrating a 31% reduction in risk of death (HR: 0.69; 95% CI: 0.54–0.89, p=0.002, n=494) compared to chemotherapy alone.

"Gynaecological oncologists have long awaited an immuno-oncology option to improve survival outcomes for endometrial cancer patients at advanced stages, and newly approved treatments in Canada enhance the cancer care journey by offering more personalized options," says Dr. Alon Altman, Gynecologic Oncologist and Professor of Obstetrics and Gynecology at the University of Manitoba, and Chief Strategy Officer and Former President of The Society of Gynecologic Oncology of Canada (GOC). "Ensuring innovative clinical therapies are publicly available and accessible to all patients in need is also vital as timely treatment is especially crucial for individuals with more advanced endometrial cancer who cannot afford to wait."

The expanded approval follows Jemperli'sNovember 2023 approval in combination with carboplatin and paclitaxel for the treatment of adult patients with primary advanced or recurrent mismatch repair deficient (dMMR)/ microsatellite instability-high (MSI-H) endometrial cancer who are candidates for systemic therapy, based on an earlier analysis of Part 1 of the RUBY study. 

Filomena Servidio-Italiano, President & CEO of the Colorectal Cancer Resource & Action Network (CCRAN), a patient advocacy group dedicated to improving the longevity and quality of life for all cancer patients in Canada, stated, "The expanded approval of dostarlimab provides patients with advanced or recurrent endometrial cancer new hope of extending their lives. Patients and advocates should be encouraged by this announcement, offering a new treatment option to patients in Canada diagnosed with endometrial cancer. We are optimistic that the Canadian reimbursement and funding systems will support the accessibility of this important therapy for those in need."

About endometrial cancer 
Endometrial cancer is found in the inner lining of the uterus, known as the endometrium. Endometrial cancer is the most common gynaecologic cancer in developed countries,^[3] with an estimated 1.6 million people living with active disease at any stage and 417,000 new cases reported each year worldwide.^[4] Incidence rates are expected to rise by approximately 40% between 2020 and 2040.^[5] In Canada, an estimated 8,600 women were diagnosed with endometrial cancer in 2024, with approximately 1,600 succumbing to the disease.^[6] Approximately 15-20% of patients with endometrial cancer will be diagnosed with advanced disease at the time of diagnosis.^[7] Among patients with primary advanced or recurrent endometrial cancer, approximately 75% have MMRp/MSS tumours.^[2]

About RUBY
RUBY is a two-part global, randomized, double-blind, multicentre phase III trial of patients with primary advanced or recurrent endometrial cancer. Part 1 evaluated dostarlimab plus carboplatin-paclitaxel followed by dostarlimab versus carboplatin-paclitaxel plus placebo followed by placebo.

In Part 1, the dual-primary endpoints are investigator-assessed PFS based on the Response Evaluation Criteria in Solid Tumours v1.1, and OS. The statistical analysis plan included pre-specified analyses of PFS in the dMMR/ MSI-H and overall populations and OS in the overall population. Pre-specified exploratory analyses of PFS and OS in the MMRp/MSS population and OS in the dMMR/MSI-H populations were also performed. RUBY Part 1 included 494 patients in efficacy analyses across a broad population, including histologies often excluded from clinical trials (approximately 10% of patients with carcinosarcoma and 20% with serous carcinoma). 

About Jemperli (dostarlimab for injection)
Jemperli is a programmed death receptor-1 (PD-1)-blocking antibody that binds to the PD-1 receptor and blocks its interaction with the PD-1 ligands PD-L1 and PD-L2. ^[8]

In Canada, Jemperli (dostarlimab for injection) is indicated in combination with carboplatin and paclitaxel for the treatment of adult patients with primary advanced or first recurrent endometrial cancer who are candidates for systemic therapy which includes patients with MMRp/MSS and dMMR/MSI-H tumours. Jemperli is also approved as monotherapy for the treatment of adult patients with dMMR/MSI-H recurrent or advanced endometrial cancer that has progressed on or following prior treatment with a platinum-containing regimen.

Please consult the Product Monograph at www.gsk.ca for complete safety information. The Product Monograph is also available by calling 1-800-387-7374.

GSK in gynaecologic oncology
GSK is committed to maximizing patient survival through transformational medicines with a current effort on breakthroughs in oncology, including gynaecologic cancers, some of the most common cancers affecting women. We are focused on developing new medicines across a range of different modalities for a variety of cancers, including ovarian and endometrial.

About GSK 
GSK is a global biopharma company with a purpose to unite science, technology, and talent to get ahead of disease together. Find out more at gsk.ca.

References

SOURCE GlaxoSmithKline Inc.