GSK data at ASCO and EHA showcase latest research and innovation across the oncology portfolio

• Latest data on belantamab mafodotin combinations underscore the potential to transform treatment of 2L+ multiple myeloma
• New analyses from MOMENTUM and SIMPLIFY-1 trials at EHA emphasise importance of early intervention with momelotinib
• New data across phase III studies at ASCO show the impact of dostarlimab and niraparib in advanced gynaecologic cancers

GSK plc (LSE/NYSE: GSK) today announced that new data across the oncology pipeline and portfolio will be presented in more than 60 abstracts at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting (30 May - 3 June) in Chicago, IL and the 30^th European Hematology Association (EHA) Congress (12 - 15 June) in Milan, Italy. These results highlight GSK's research and development programmes which aim to improve outcomes for patients with blood cancers, gynaecologic cancers and other solid tumours through innovative therapeutic approaches.

Reinforcing the potential for belantamab mafodotin to redefine treatment of relapsed/refractory multiple myeloma

At ASCO and EHA, GSK will share updated data from the DREAMM (DRiving Excellence in Approaches to Multiple Myeloma) programme. Key presentations include:

• Updated progression-free survival (PFS) analysis from the DREAMM-8 study (EHA abstract #PF728).
• DREAMM-8 data shows the association of measurable residual disease (MRD) negativity with efficacy endpoints (ASCO abstract #7515).
• First presentation of safety and efficacy data from DREAMM-20 evaluating the unconjugated monoclonal antibody, belantamab. This represents an important first step towards exploring next-generation BCMA solutions (ASCO abstract #7550).
• A new analysis from DREAMM-7 and DREAMM-8 which contextualise manageability of eye-related side effects including impact on reading and driving (EHA abstract #PS1761).

Importance of starting treatment early with momelotinib which may impact survival in myelofibrosis patients

At EHA 2025, new analyses from the pivotal MOMENTUM and SIMPLIFY-1 trials reinforce momelotinib as a standard of care in myelofibrosis (MF), The data explore the benefits of initiating treatment for myelofibrosis earlier, which could lead to better outcomes for patients. Presentations include:

• New post-hoc analyses from the MOMENTUM & SIMPLIFY-1 trials show addressing anaemia and achieving haemoglobin improvement of 10 g/dL or above may positively impact overall survival (EHA abstract #PF828).
• New SIMPLIFY-1 subgroup data show the impact of patients achieving both ≥ 35% spleen volume reduction (SVR35) and transfusion independence responses with momelotinib, which are prioritised in treatment guidelines to support optimal long-term outcomes in patients (EHA abstract #PS1829).

Understanding the impact of our medicines on quality of life for patients with gynaecologic cancers

Findings from GSK’s gynaecologic cancer portfolio focus on understanding the patient treatment experience to better inform GSK’s research efforts and clinical care. These include:

• Results of the phase III FIRST-ENGOT-OV44 trial provides insight on the role of adding dostarlimab to platinum-based chemotherapy followed by niraparib maintenance, with or without bevacizumab, in first-line advanced ovarian cancer (ASCO abstract #LBA5506).
• Patient reported outcomes from the phase III PRIMA trial (ENGOT-OV26/GOG-3012) will help inform healthcare providers on the impact of disease progression on quality of life in patients with newly diagnosed advanced ovarian cancer (ASCO abstract #5551).
• New post-hoc analysis from Part 1 of the phase III RUBY trial (EN6-NSGO/GOG-3031) evaluates time to changes in quality of life with dostarlimab plus chemotherapy (carboplatin-paclitaxel) compared to chemotherapy alone in patients with primary advanced or recurrent endometrial cancer (ASCO abstract #5600).

Full list of GSK’s presentations at ASCO:

Belantamab Mafodotin

Dostarlimab

Niraparib

Full list of Alliance, investigator-initiated studies and supported collaborative studies at ASCO:

Full list of GSK presentations at EHA:

Belantamab Mafodotin

Momelotinib

Full list of Alliance, investigator-initiated studies and supported collaborative studies at EHA:

About multiple myeloma

Multiple myeloma is the third most common blood cancer globally and is generally considered treatable but not curable.^1,2 There are approximately more than 180,000 new cases of multiple myeloma diagnosed globally each year.³ Research into new therapies is needed as multiple myeloma commonly becomes refractory to available treatments.⁴ Many patients with multiple myeloma are treated in a community cancer setting, leaving an urgent need for new, effective therapies with manageable side effects that can be administered outside of an academic centre.^5,6

About myelofibrosis

Myelofibrosis is a rare blood cancer that disrupts the body’s normal production of blood cells because of dysregulated JAK-signal transducer and activator of transcription protein signalling. The clinical hallmarks of myelofibrosis are splenomegaly (enlarged spleen), severely low blood counts, including anaemia and thrombocytopenia, and debilitating constitutional symptoms, such as fatigue, night sweats and bone pain, attributable to ineffective haematopoiesis and excessive production of proinflammatory cytokines.^7,8

About ovarian cancer

Ovarian cancer is the eighth most common cancer in women worldwide.⁹ Despite high response rates to platinum-based chemotherapy in the first-line setting, approximately 85% of patients will experience disease recurrence. Once the disease recurs, it is rarely curable, with decreasing time intervals to each subsequent recurrence.¹⁰

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,¹¹ with an estimated 1.6 million people living with active disease at any stage and 417,000 new cases reported each year worldwide.¹⁶ Incidence rates are expected to rise by approximately 40% between 2020 and 2040.¹² In Europe, approximately 121,000 people are estimated to be diagnosed with primary advanced or recurrent endometrial cancer each year.¹³ Approximately 15-20% of patients with endometrial cancer will be diagnosed with advanced disease at the time of diagnosis.¹⁴ Among patients with primary advanced or recurrent endometrial cancer, approximately 75% have MMRp/MSS tumours.¹⁵

About dMMR/MSI-H rectal cancer

Rectal cancer is a form of cancer that starts in the rectum, the final section of the large intestine, and is often categorised as part of a group of cancers called colorectal cancer. Colorectal cancer is the third most commonly diagnosed cancer in the world.¹⁶ In the US, it is estimated that approximately 46,220 individuals are diagnosed annually with rectal cancer.¹⁷ Approximately 5-10% of all rectal cancers are dMMR/MSI-H, meaning that they contain abnormalities that affect the proper repair of DNA when copied in a cell.¹⁸ Mismatch repair deficient status is a biomarker that has been shown to predict response to immune checkpoint blockade with PD-1 therapy.^19,20 Tumours with this biomarker are most commonly found in endometrial, colorectal and other gastrointestinal cancers but may also be found in other solid tumours.^21,22,23,24

About glioblastoma

Glioblastoma is a type of cancer that starts as a growth of cells in the brain or spinal cord. It grows quickly and can invade and destroy healthy tissue.²⁵ It accounts for more than half of all primary malignant brain tumours and is one of the most complex and treatment-resistant cancers, resulting in poor patient outcomes.²⁶ Survival rates and mortality statistics for glioblastoma have been virtually unchanged for decades, highlighting the need to investigate new treatment options.²⁶

About Blenrep (belantamab mafodotin)

Belantamab mafodotin is an ADC comprising a humanised BCMA monoclonal antibody conjugated to the cytotoxic agent auristatin F via a non-cleavable linker. The drug linker technology is licensed from Seagen Inc.; the monoclonal antibody is produced using POTELLIGENT Technology licensed from BioWa Inc., a member of the Kyowa Kirin Group.

In April 2025, the UK Medicines and Healthcare products Regulatory Agency (MHRA) licensed belantamab mafodotin combinations for the treatment of relapsed or refractory multiple myeloma in adult patients who have received at least one prior therapy. In May 2025, the Japan Ministry of Health, Labour and Welfare approved belantamab mafodotin for the treatment of adults with relapsed or refractory multiple myeloma.

Important information for belantamab mafodotin in the United Kingdom

Indication

In the UK, belantamab mafodotin is indicated in adults for the treatment of multiple myeloma:

• in combination with bortezomib and dexamethasone in patients who have received at least one prior therapy; and
• in combination with pomalidomide and dexamethasone in patients who have received at least one prior therapy including lenalidomide.

IMPORTANT SAFETY INFORMATION FOR BLENREP

More information can be found in the Blenrep Summary of Product Characteristics and Patient Information leaflets available on the MHRA Products website.

About Omjjara (momelotinib)

Momelotinib has a differentiated mechanism of action, with inhibitory ability along three key signalling pathways: Janus kinase (JAK) 1, JAK2, and activin A receptor, type I (ACVR1).^27,28,29,30 Inhibition of JAK1 and JAK2 may improve constitutional symptoms and splenomegaly.^27,28,30 Additionally, inhibition of ACVR1 leads to a decrease in circulating hepcidin levels, potentially contributing to anaemia-related benefit.^27,28,29,30

In September 2023, the US Food and Drug Administration licensed³¹ momelotinib under the brand name Ojjaara for the treatment of intermediate or high-risk myelofibrosis, including primary myelofibrosis or secondary myelofibrosis (post-polycythaemia vera and post-essential thrombocythemia), in adults with anaemia.

In January 2024, the European Commission granted marketing authorisation³² for momelotinib for disease-related splenomegaly (enlarged spleen) or symptoms in adult patients with moderate to severe anaemia who have primary myelofibrosis, post polycythaemia vera myelofibrosis or post essential thrombocythemia myelofibrosis and who are Janus kinase (JAK) inhibitor naïve or have been treated with ruxolitinib. Momelotinib was also approved³³ by the Medicines and Healthcare products Regulatory Agency (MHRA) in the United Kingdom to treat the symptoms experienced by adult myelofibrosis patients who have moderate or severe anaemia.

In June 2024, the Japan Ministry of Health, Labour and Welfare (MHLW) approved³⁴ momelotinib for the treatment of myelofibrosis.

Important information for momelotinib in the EU

Indication

Momelotinib is indicated for the treatment of disease-related splenomegaly (enlarged spleen) or symptoms in adult patients with moderate to severe anaemia who have primary myelofibrosis, post polycythaemia vera myelofibrosis or post essential thrombocythaemia myelofibrosis and who are Janus kinase (JAK) inhibitor naïve or have been treated with ruxolitinib.

Refer to the Omjjara EMA Reference Information for a full list of adverse events and the complete important safety information in the EU.

About Zejula (niraparib)

Niraparib is an oral, once-daily Poly (ADP-ribose) polymerase (PARP) inhibitor indicated in the US for the maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in complete or partial response to first-line platinum-based chemotherapy; and for the maintenance treatment of adult patients with deleterious or suspected deleterious germline BRCA-mutated recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to platinum-based chemotherapy and who have been selected based on a US FDA-approved companion diagnostic for niraparib.

Important information for niraparib in the EU

Indication

Niraparib is indicated:

• as monotherapy for the maintenance treatment of adult patients with advanced epithelial (FIGO Stages III and IV) high-grade ovarian, fallopian tube or primary peritoneal cancer who are in response (complete or partial) following completion of first-line platinum-based chemotherapy.
• as monotherapy for the maintenance treatment of adult patients with platinum-sensitive relapsed high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in response (complete or partial) to platinum-based chemotherapy.

Refer to the Zejula EMA Reference Information for a full list of adverse events and the complete important safety information in the EU.

About Jemperli (dostarlimab)

Dostarlimab, a programmed death receptor-1 (PD-1)-blocking antibody, is the backbone of GSK’s ongoing immuno-oncology-based research and development programme. A robust clinical trial programme includes studies of dostarlimab alone and in combination with other therapies in gynaecologic, colorectal and lung cancers, as well as where there are opportunities for transformational outcomes.

In the US, dostarlimab is indicated in combination with carboplatin and paclitaxel, followed by dostarlimab as a single agent for the treatment of adult patients with primary advanced or recurrent endometrial cancer. This includes patients with MMRp/MSS and dMMR/MSI-H tumours. Dostarlimab is also approved as a single agent for adult patients with dMMR recurrent or advanced endometrial cancer, as determined by a US FDA-approved test, that has progressed on or following a prior platinum-containing regimen in any setting and are not candidates for curative surgery or radiation. Additionally, dostarlimab is indicated in the US for patients with dMMR recurrent or advanced solid tumours, as determined by a US FDA-approved test, that have progressed on or following prior treatment and who have no satisfactory alternative treatment options. The latter indication is approved in the US under accelerated approval based on tumour response rate and durability of response. Continued approval for this indication in solid tumours may be contingent upon verification and description of clinical benefit in a confirmatory trial(s). 

Dostarlimab was discovered by AnaptysBio, Inc. and licensed to TESARO, Inc., under a collaboration and exclusive license agreement signed in March 2014. Under this agreement, GSK is responsible for the ongoing research, development, commercialisation, and manufacturing of dostarlimab and cobolimab (GSK4069889), a TIM-3 antagonist. 

Important information for dostarlimab in the EU

Indication

Dostarlimab is indicated:

• in combination with carboplatin and paclitaxel, for the treatment of adult patients with mismatch repair deficient (dMMR)/microsatellite instability-high (MSI-H) primary advanced or recurrent endometrial cancer and who are candidates for systemic therapy;
• as monotherapy for treating adult patients with mismatch repair deficient (dMMR)/microsatellite instability-high (MSI-H) recurrent or advanced endometrial cancer that has progressed on or following prior treatment with a platinum-containing regimen.

Refer to the Jemperli EMA Reference Information for a full list of adverse events and the complete important safety information in the EU.

GSK in oncology

Our ambition in oncology is to help increase overall quality of life and deliver practice-changing potential to modify the course of disease, expanding from our current focus on blood and women’s cancers into lung and gastrointestinal cancers, as well as other solid tumours. This includes accelerating priority programmes such as antibody-drug conjugates targeting B7-H3 and B7-H4, and IDRX-42, a highly selective KIT tyrosine kinase inhibitor.

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.com.

Cautionary statement regarding forward-looking statements

GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Such factors include, but are not limited to, those described in the “Risk Factors” section in GSK’s Annual Report on Form 20-F for 2024, and GSK’s Q1 Results for 2025.

References

1. Sung H, Ferlay J, Siegel R, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-249. doi:10.3322/caac.21660.
2. Kazandjian D. Multiple myeloma epidemiology and survival: A unique malignancy. Semin Oncol. 2016;43(6):676–681.doi: 10.1053/j.seminoncol.2016.11.004.
3. Global Cancer Observatory. International Agency for Research on Cancer. World Health Organization. Multiple Myeloma fact sheet. Available at: https://gco.iarc.who.int/media/globocan/factsheets/cancers/35-multiple-myeloma-fact-sheet.pdf. Accessed 5 March 2025.
4. Nooka AK, Kastritis E, Dimopoulos MA. Treatment options for relapsed and refractory multiple myeloma. Blood. 2015;125(20). doi:10.1182/blood-2014-11-568923.
5. Gajra A, Zalenski A, Sannareddy A, et al. Barriers to Chimeric Antigen Receptor T-Cell (CAR-T) Therapies in Clinical Practice. Pharmaceut Med. 2022 Jun;36(3):163-171.
6. Crombie J, Graff T, Falchi L, et al. Consensus recommendations on the management of toxicity associated with CD3×CD20 bispecific antibody therapy. Blood (2024) 143 (16): 1565–1575.
7. Atallah E, Verstovsek S. Emerging drugs for myelofibrosis. Expert Opin Emerg Drugs. 2012 Dec;17(4):555-70. doi: 10.1517/14728214.2012.748748. PMID: 23186315; PMCID: PMC5009610.
8. MPN Research Foundation. Primary Myelofibrosis (PMF). 2021. Accessed August 2022. http://www.mpnresearchfoundation.org/primary-myelofibrosis-pmf/
9. Worldwide Cancer Data. World Cancer Research Fund. https://www.wcrf.org/cancer-trends/ovarian-cancer-statistics/. Updated March 23, 2022. Accessed November 2024.
10. Lorusso D, Mancini M, Di Rocco R, Fontanelli R, Raspagliesi F. The role of secondary surgery in recurrent ovarian cancer [published online August 5, 2012]. Int J Surg Oncol. 2012. doi:10.1155/2012/613980. Accessed November 2024.
11. Faizan U, Muppidi V. Uterine Cancer. [Updated 2022 Sep 5]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan. Available at: www.ncbi.nlm.nih.gov/books/NBK562313/.
12. Sung H, Ferlay J, Siegel R, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-249. doi:10.3322/caac.21660.
13. Concin N, Matias-Guiu X, Vergote I, et al ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma International Journal of Gynecologic Cancer 2021;31:12-39.
14. CMP: CancerMPact® Patient Metrics Mar-2023, Cerner Enviza. Available at www.cancermpact.com. Accessed 18 December 2024.
15. Based on CMP:CancerMPact® [Patient Metrics], Cerner Enviza. Available from www.cancermpact.com. Accessed 18 December 2024.
16. Sung H, Ferlay J, Siegel RL, et al. Global Cancer Statistics 2020: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries. CA Cancer J Clin. 2021;71(3):209-249. doi:10.3322/caac.21660.
17. Siegel RL, Giaquinto AN, Jemal A. Cancer statistics, 2024. CA Cancer J Clin. 2024;74(1):12-49. doi:10.3322/caac.21820
18. Cercek A, et al. Mismatch Repair-Deficient Rectal Cancer and Resistance to Neoadjuvant Chemotherapy. Clin Cancer Res. 2020 Jul 1;26(13):3271-3279. doi: 1158/1078-0432.CCR-19-3728. Epub 2020 Mar 6. PMID: 32144135; PMCID: PMC7348681.
19. Le DT, et al. PD-1 blockade in tumors with mismatch repair deficiency. N Engl J Med. 2015;372(26):2509-2520.
20. Andre T, Berton D, Curigliano G, et al. Antitumor Activity and Safety of Dostarlimab Monotherapy in Patients With Mismatch Repair Deficient Solid Tumors: A Nonrandomized Controlled Trial. JAMA Netw Open. 2023;6(11):e2341165. doi:10.1001/jamanetworkopen.2023.41165
21. National Cancer Institute at the National Institutes of Health. Definition of mismatch repair deficiency. Accessed April 19, 2024. Available at: https://www.cancer.gov/publications/dictionaries/cancer-terms/def/mismatch-repair-deficiency.
22. Lorenzi M, et al. Epidemiology of microsatellite instability high (MSI-H) and deficient mismatch repair (dMMR) in solid tumors: a structured literature review. J Oncol. 2020. doi.org/10.1155/2020/1807929.
23. Zhao P, et al. Mismatch repair deficiency/microsatellite instability-high as a predictor for anti-PD-1/PD-L1 immunotherapy efficacy. J Hematol Oncol. 2019;12(1):54. doi: 10.1186/s13045-019-0738-1.
24. 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.
25. Mayo Clinic: Glioblastoma. Mayclinic.org. Accessed April 19, 2024. Available at: https://www.mayoclinic.org/diseases-conditions/glioblastoma/cdc-20350148#:~:text=Glioblastoma%20is%20a%20type%20of,invade%20and%20destroy%20healthy%20tissue
26. National Brain Tumur Society: About Glioblastoma. Braintumor.org. https://braintumor.org/events/glioblastoma-awareness-day/about-glioblastoma/
27. Chifotides, HT, Bose, P, Verstovsek, S. Momelotinib: an emerging treatment for myelofibrosis patients with anemia. J Hematol Oncol. 2022;15(7):1-18.
28. Verstovsek S, et al. MOMENTUM: momelotinib vs danazol in patients with myelofibrosis previously treated with JAKi who are symptomatic and anemic. Future Oncol. 2021;17(12):1449-1458.
29. Asshoff M, et al. Momelotinib inhibits ACVR1/ALK2, decreases hepcidin production, and ameliorates anemia of chronic disease in rodents. Blood. 2017;129(13):1823-1830.
30. Oh S, et al. ACVR1/JAK1/JAK2 inhibitor momelotinib reverses transfusion dependency and suppresses hepcidin in myelofibrosis phase 2 trial. Blood Adv. 2020;4(18):4282-4291.
31. GSK press release issued 15 September 2023: Ojjaara (momelotinib) approved in the US as the first and only treatment indicated for myelofibrosis patients with anaemia. Available at https://www.gsk.com/en-gb/media/press-releases/ojjaara-momelotinib-approved-in-the-us-as-the-first-and-only-treatment-indicated-for-myelofibrosis-patients-with-anaemia/
32. GSK press release issued 29 January 2024: European Commission authorises GSK’s Omjjara (momelotinib). Available at https://www.gsk.com/en-gb/media/press-releases/european-commission-authorises-gsk-s-omjjara-momelotinib/
33. MHRA press release issued 31 January 2024: Omjjara licensed for anaemic myelofibrosis patients to treat the symptoms of their disease. Available at https://www.gov.uk/government/news/omjjara-licensed-for-anaemic-myelofibrosis-patients-to-treat-the-symptoms-of-their-disease
34. GSK press release issued 24 June 2024: GSK’s Omjjara (momelotinib) approved in Japan for treatment of myelofibrosis. Available at https://www.gsk.com/en-gb/media/press-releases/gsk-s-omjjara-momelotinib-approved-in-japan-for-treatment-of-myelofibrosis/