Jemperli in combination with chemotherapy is the first immuno-oncology treatment approved in the frontline setting for this patient population in Singapore.[1,2] Latest published local registry reported endometrial cancer as the fourth most common cancer and had the ninth highest cancer mortality rate among females in the country.[3] An estimated 20-29% of all endometrial cancers globally are dMMR/MSI-H.[4] Chemotherapy used alone has been the current standard of care for primary advanced or recurrent endometrial cancer, and many patients eventually experience disease progression.[5] SINGAPORE, Aug. 7, 2024 /PRNewswire/ -- GSK Singapore today announced that the Singapore Health Sciences Authority (HSA) has approved a new indication for Jemperli (dostarlimab), which may now be used in combination with carboplatin and paclitaxel, followed by Jemperli as a single agent for the treatment of adult patients with primary advanced or recurrent endometrial cancer that is mismatch repair deficient (dMMR) or microsatellite instability-high (MSI-H).[1]

With this approval, Jemperli is now indicated earlier in treatment, in combination with chemotherapy, for patients with dMMR/MSI-H primary advanced or recurrent endometrial cancer. Jemperli has earlier received approval from Singapore HSA as a monotherapy in adult patients with dMMR recurrent or advanced endometrial cancer that has progressed on or following a prior platinum-containing regimen in any setting and are not candidates for curative surgery or radiation.[1]

Latest Singapore Cancer Registry, from 2017-2021, reported endometrial cancer as the fourth most common and had the ninth highest cancer mortality rate among females in the country, with 3,133 new cases diagnosed during the period.[3] Approximately 15-20% of endometrial cancer patients globally and 28% in Singapore were at advanced disease stage at the time of diagnosis.[3,4] An estimated 20-29% of all endometrial cancers globally are dMMR/MSI-H.[4] Chemotherapy used alone has been the current standard of care for primary advanced or recurrent endometrial cancer, and many patients eventually experience disease progression.[5]

Dr. Stephanie Cinthu Stephen Ambrose, GSK Singapore Medical Director, said: "Singapore's expanded regulatory approval of Jemperli redefines the treatment landscape for patients with dMMR/MSI-H primary advanced or recurrent endometrial cancer in Singapore. Until now, chemotherapy alone has been the standard of care with many patients experiencing disease progression. In GSK's RUBY trial, Jemperli plus chemotherapy demonstrated a 72% reduction in the risk of disease progression or death versus chemotherapy in this patient population, providing a statistically significant and clinically meaningful benefit. These results underscore the potential for Jemperli to transform cancer treatment as a backbone immuno-oncology therapy."

Dr. John Chia of Curie Oncology, Singapore, said: "Metastatic endometrial cancer is an aggressive disease with poor outcomes, and doctors sometimes struggle with limited effective treatment options. The results of the RUBY trial represent a clinical breakthrough in decades for dMMR/MSH-I endometrial cancer (or commonly known as uterine cancer). With this new approved treatment combination, many patients with primary advanced or recurrent dMMR endometrial cancer in Singapore will now have an opportunity for potential complete remission, with maximal benefit when given early in the treatment."

GSK's submission to the Singapore's regulatory body included interim analysis results from Part 1 of the RUBY/ENGOT-EN6/GOG3031/NSGO Phase III trial, which reflect a robust median duration of follow-up of ≥ 25 months. The trial met the primary endpoint of investigator-assessed progression-free survival (PFS), demonstrating a statistically significant and clinically meaningful benefit in patients treated with Jemperli plus carboplatin and paclitaxel in the dMMR/MSI-H population. In the dMMR/MSI-H population, a 72% reduction in the risk of disease progression or death was observed.[1]

The safety and tolerability profile for Jemperli plus carboplatin and paclitaxel was generally consistent with the known safety profiles of the individual agents. The most common treatment-emergent adverse events (≥ 20%) in patients receiving Jemperli plus chemotherapy were rash, diarrhoea, hypothyroidism, and hypertension.[1]

Artistic representation of endometrial cancer (image by GSK)

GSK Asia House Singapore (image by GSK)

About endometrial cancer

Endometrial cancer is one of the most common gynaecologic cancers in developed countries.[3] According to latest Singapore Cancer Registry data, from 2017-2021, endometrial cancer was the fourth most common cancer and had the ninth highest cancer mortality rate among females.[3] There are about 3,133 new cases of endometrial cancer diagnosed between the 2017 - 2021.[3] Approximately 15-20% of endometrial cancer patients globally and 28% in Singapore were at advanced disease stage at the time of diagnosis.[3,4] An estimated 20-29% of all endometrial cancers globally are dMMR/MSI-H.[4] Chemotherapy used alone has been the current standard of care for primary advanced or recurrent endometrial cancer, and many patients eventually experience disease progression.[5]

About RUBY

RUBY is a two-part global, randomised, double-blind, multicentre phase III trial of patients with primary advanced or recurrent endometrial cancer. Part 1 is evaluating dostarlimab plus carboplatin-paclitaxel followed by dostarlimab versus carboplatin-paclitaxel plus placebo followed by placebo. Part 2 is evaluating dostarlimab plus carboplatin- paclitaxel followed by dostarlimab plus niraparib versus placebo plus carboplatin-paclitaxel followed by placebo.

The dual-primary endpoints in Part 1 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 ITT populations and OS in the overall population. Pre-specified exploratory analyses of PFS in the mismatch repair proficient (MMRp)/microsatellite stable (MSS) population and OS in the dMMR/MSI-H populations were also performed. RUBY Part 1 included a broad population, including histologies often excluded from clinical trials and had approximately 10% of patients with carcinosarcoma and 20% with serous carcinoma. In Part 2, the primary endpoint is investigator-assessed PFS. Secondary endpoints in Part 1 and Part 2 include PFS per blinded independent central review, overall response rate, duration of response, disease control rate, patient-reported outcomes, and safety and tolerability.

The RUBY trial data (https://www.gsk.com/en-gb/media/press-releases/phase-iii-ruby-clinical-trial-demonstrates- potential-of-Jemperli-plus-chemotherapy-to-redefine-the-treatment-of-primary-advanced-or-recurrent-endometrial- cancer/) were presented at the European Society for Medical Oncology (ESMO) Virtual Plenary and Society of Gynecologic Oncology (SGO) Annual Meeting on 27 March 2023, and were simultaneously published in The New England Journal of Medicine.

About Jemperli (dostarlimab)

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.[6] In Singapore, Jemperli is indicated in combination with carboplatin and paclitaxel, followed by Jemperli as a single agent for the treatment of adult patients with primary advanced or recurrent endometrial cancer that is mismatch repair deficient (dMMR, or microsatellite instability-high (MSI-H), and as a single agent for adult patients with mismatch repair-deficient (dMMR) recurrent or advanced endometrial cancer, that has progressed on or following a prior platinum-containing regimen in any setting and are not candidates for curative surgery or radiation.

Jemperli was discovered by AnaptysBio, Inc. and licensed to TESARO, Inc., under a collaboration and exclusive license agreement signed in March 2014.

Information on indication, dosing, and contraindications per Singapore's National Drug Formulary

www.ndf.gov.sg/monograph/detail/M01739

GSK in Oncology

GSK is committed to maximising patient survival through transformational medicines, with a current focus on breakthroughs in immuno-oncology and tumour-cell targeting therapies, and development in haematologic malignancies, gynaecologic cancers, and other solid tumours.

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 https://www.gsk.com/en-gb/locations/singapore/

For media queries, please contact:

Rommel Abuda

GSK Singapore

rommel.j.abuda@gsk.com

Rae Chew (on behalf of GSK Singapore)

PR Rae

rae.chew@pr-rae.com

References

1 Jemperli (dostarlimab) Singapore Prescribing Information, 2024.

2 HSA infosearch: https://www.hsa.gov.sg/e-services/infosearch

3 Singapore Cancer Registry Annual Report, 2021

4 Bonneville R. JCO precision oncology. 2017;2017;1-15

5 Miller DS. J Clin Oncol. 2020;38;3841-3850

6 Laken H, Kehry M, Mcneeley P, et al. Identification and characterization of TSR-042, a novel anti-human PD-1 therapeutic antibody. European Journal of Cancer. 2016;69, S102. doi:10.1016/s0959-8049(16)32902-1.