On June 2, 2024, Simcere Zaiming, a leading oncology company and subsidiary of Simcere Pharmaceutical Group Ltd., announced the presentation of the latest data from the registrational phase 3 clinical study of suvemcitug for the treatment of platinum-resistant ovarian cancer. The findings were shared as a Late-Breaking Abstract (LBA) oral presentation at the annual meeting of the American Society of Clinical Oncology (ASCO) in 2024.
The SCORES Study (NCT04908787), a multicenter, randomized, double-blind, placebo-controlled phase 3 trial, was designed to assess the efficacy and safety of suvemcitug in combination with the investigator’s choice of chemotherapy—paclitaxel, liposomal doxorubicin, or topotecan—for treating platinum-resistant ovarian cancer. Led by Professor Lingying Wu of the Cancer Hospital Chinese Academy of Medical Sciences, the study enrolled 421 patients across 55 sites in China from June 2021 to June 2023. These patients had recurrent epithelial ovarian cancer, fallopian tube cancer, or primary peritoneal cancer and had not responded to platinum-based chemotherapy. On January 3, 2024, the SCORES study successfully met its primary endpoint.
Key Findings from the Study:
1. Progression-Free Survival (PFS): The Blinded Independent Review Committee (BIRC) reported that the experimental arm showed a significant extension in PFS compared to the control arm, with a median PFS of 5.49 months versus 2.73 months (hazard ratio [HR] 0.46, P<0.0001).
2. Subgroup Efficacy: Positive results and significant improvements in PFS were observed across all predefined subgroups, including age, ECOG performance status, presence of ascites, baseline lesion size, number of prior therapy lines, platinum-free interval, number of prior systemic therapies, prior anti-angiogenic therapy, platinum-refractory status, and choice of combination chemotherapy regimen.
3. Prior Treatments: Among the participants, 50.1% had previously received VEGF pathway-targeted therapy, and 48.9% had been treated with PARP inhibitors. The study indicated that suvemcitug, when used in conjunction with chemotherapy, significantly improved PFS in patients with prior VEGF and/or PARP inhibitor treatments.
4. Overall Survival (OS): At the time of the primary endpoint analysis, OS data was still maturing, with the median follow-up durations being 14.36 months for the experimental arm and 14.26 months for the control arm. Preliminary results showed a trend towards a survival benefit in the experimental arm, with a median OS of 16.07 months compared to 14.88 months in the control arm (HR 0.79, p=0.1244).
5. Secondary Efficacy Endpoints: The experimental arm demonstrated superior outcomes in other secondary efficacy measures, including median PFS assessed by investigators (5.39 months vs. 2.46 months), objective response rates (ORR) by BIRC (26.0% vs. 12.1%), ORR by investigators (23.1% vs. 8.6%), and consistent benefits in disease control rate (DCR) and duration of response (DOR).
6. Safety Profile: Suvemcitug combined with chemotherapy was well-tolerated, exhibiting a favorable safety profile with no new safety concerns relative to other drugs in the same class.
Professor Lingying Wu,Leading PI of the SCORES Study commented:"It is with profound honor that we present this landmark study to the global academic community on behalf of our dedicated research team. The SCORES trial represents a pioneering advancement as the first phase 3 clinical study in platinum-resistant ovarian cancer to employ a double-blind control methodology. This study has incorporated the three chemotherapy regimens most frequently endorsed by current guidelines. Notably, the inclusion criteria for subjects were not constrained by prior treatments targeting the VEGF pathway. As a pivotal phase 3 registration study, it boasts the largest cohort size for this medical indication. The findings from the SCORES trial indicate that the combination of suvemcitug with chemotherapy markedly enhances anti-tumor efficacy and confers a survival advantage for patients afflicted with platinum-resistant ovarian cancer.”
Professor Yuan Guangwen, SubI of the SCORES study, disseminated the latest data from the trial during an oral presentation at the ASCO 2024 conference in Chicago, United States.
Overview of Suvemcitug
Suvemcitug is an innovative, next-generation recombinant humanized anti-VEGF rabbit monoclonal antibody, jointly developed by Simcere and Apexigen, Inc. Simcere Zaiming holds exclusive development and commercialization rights for this product within Greater China. Preclinical studies have demonstrated that Suvemcitug exhibits superior affinity and anti-tumor efficacy compared to Bevacizumab at equivalent dosages across various tumor models. Early-phase clinical trials in China have preliminarily affirmed its promising safety profile and efficacy for ovarian cancer treatment. Concurrently, a multi-cohort, open-label, multicenter Phase 2 clinical trial conducted by Simcere is evaluating the efficacy and safety of Envafolimab (PD-L1) in combination with Suvemcitug, with or without chemotherapy, in patients with advanced solid tumors. The results for cohorts with hepatocellular carcinoma, non-small cell lung cancer, and colorectal cancer, presented at the 2023 ESMO conference, revealed that the combination of Envafolimab and Suvemcitug exhibits notable anti-tumor activity and a manageable safety profile in solid tumors.
About Apexigen
Apexigen is a clinical-stage biopharmaceutical enterprise dedicated to the discovery and development of novel antibody-based therapeutics for oncology. On August 23, 2023, Apexigen was acquired by Pyxis Oncology, Inc. (NASDAQ: PYXS, Pyxis), a clinical-stage entity committed to overcoming challenging cancers by developing a new generation of therapeutics suitable for both mono and combination therapies.
About Simcere Zaiming
Simcere Zaiming, an oncology-centric biopharmaceutical subsidiary of Simcere Pharmaceutical Group Limited (HKEX: 2096, “Simcere”), was established in 2023. The company is devoted to crafting groundbreaking therapies aimed at fulfilling the unmet clinical needs of cancer patients globally. With a robust and innovative R&D pipeline featuring distinct clinical assets, Simcere Zaiming has successfully launched several products in China, including COSELA®, Endostar®, and Envafolimab. The company is determined to deliver potentially transformative treatment options to cancer patients worldwide through its internal R&D, manufacturing, and commercialization capabilities, complemented by strategic collaborations with leading partners in the field of innovative cancer therapeutics. For media inquiries, please contact: pr@zaiming.com