SCR-6852, an oral and highly brain-penetrating estrogen receptor degrader (SERD), effectively shrinks tumors both in intracranial and subcutaneous ER + breast cancer models

Breast Cancer Research

Research

Peng Gu¹  Yajing Liu²  Ji Zhu²  Jinwen Shan²  Yao Guo²  Linlin Yuan²  Guimei Yang²  Feng Tang³  Liting Xue⁴  Feng Zhou⁴  Renhong Tang⁵ 

[1] Jiangsu Simcere Pharmaceutical Co., Ltd., Nanjing, China;Simcere Zaiming Pharmaceutical Co., Ltd., Shanghai, China;State Key Laboratory of Neurology and Oncology Drug Development, Nanjing, China;Jiangsu Simcere Pharmaceutical Co., Ltd., Nanjing, China;State Key Laboratory of Neurology and Oncology Drug Development, Nanjing, China;Simcere Zaiming Pharmaceutical Co., Ltd., Shanghai, China;State Key Laboratory of Neurology and Oncology Drug Development, Nanjing, China;Simcere Zaiming Pharmaceutical Co., Ltd., Shanghai, China;Jiangsu Simcere Pharmaceutical Co., Ltd., Nanjing, China;

关键词: SCR-6852;    SERD;    Fulvestrant;    Estrogen receptor;    Breast cancer;    Breast cancer brain metastasis;   

DOI  :  10.1186/s13058-023-01695-4

 received in 2023-04-26, accepted in 2023-08-05,  发布年份 2023

来源: Springer

【 摘 要 】

BackgroundTargeted estrogen receptor degradation has been approved to effectively treat ER + breast cancers. Due to the poor bioavailability of fulvestrant, the first generation of SERD, many efforts were made to develop oral SERDs. With the approval of Elacestrant, oral SERDs demonstrated superior efficacy than fulvestrant. However, due to the poor ability of known SERDs to penetrate the blood–brain barrier (BBB), breast cancer patients with brain metastasis cannot benefit from clinical SERDs.MethodsThe ER inhibitory effects were evaluated on ERα protein degradation, and target genes downregulation. And anti-proliferation activities were further determined in a panel of ER + breast cancer cell lines. The subcutaneous and intracranial ER + tumor models were used to evaluate the efficacy of anti-tumor effects. Brain penetrability was determined in multiple animal species.ResultsSCR-6852 is a novel SERD and currently is under early clinical evaluation. In vitro studies demonstrated that it strongly induced both wildtype and mutant ERα degradation. It potently inhibited cell proliferation in a panel of ER + breast cancer cell lines, including the cell lines containing ESR1 mutations (Y537 and D538). Furthermore, SCR-6852 exhibited pure antagonistic activities on the ERɑ signal axis identified both in vitro and in vivo. Oral administration of SCR-6852 at 10 mg/kg resulted in tumor shrinkage which was superior to Fulvestrant at 250 mg/kg, notably, in the intracranial tumor model, SCR-6852 effectively inhibited tumor growth and significantly prolonged mice survival, which correlated well with the high exposure in brains. In addition to mice, SCR-6852 also exhibited high brain penetrability in rats and dogs.ConclusionsSCR-6852 is a novel SERD with high potency in inducing ERα protein degradation and pure antagonistic activity on ERɑ signaling in vitro and in vivo. Due to the high brain penetrability, SCR-6852 could be used to treat breast patients with brain metastasis.

【 授权许可】

CC BY   
© BioMed Central Ltd., part of Springer Nature 2023

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