Optimizing a small molecule inhibitor of SARS-CoV-2 replication and associated cytokine storm

优化 SARS-CoV-2 复制和相关细胞因子风暴的小分子抑制剂

• 批准号: 10187861
• 负责人: JEFFREY S GLENN
• 金额: $ 79.9万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10187861
• 关键词: 2019-nCoV; Address; Animal Model; Antiviral Agents; Antiviral resistance; Back; Bioavailable; Biological Availability; Buffers; COVID-19; CYP3A4 gene; Caco-2 Cells; Cells; Development; Disease; Dose; Drug Kinetics; Enterovirus; Enterovirus 71; Future; Goals; Golgi Apparatus; Hour; Human; IL8 gene; In Vitro; Interferons; Interleukin-6; Lead; Lipids; Maximum Tolerated Dose; Mediating; Metabolic; Metabolism; Modeling; Modification; Mus; Oral; Organelles; Peripheral Blood Mononuclear Cell; Permeability; Pharmaceutical Chemistry; Phosphatidylinositols; Phosphotransferases; Production; Protein Isoforms; Resistance; Resistance development; Ritonavir; Role; SARS coronavirus; SARS-CoV-2 infection; SARS-CoV-2 inhibitor; Serum; Severe Acute Respiratory Syndrome; Site; Small Interfering RNA; Structure-Activity Relationship; Testing; Therapeutic Index; Tissues; Toxic effect; Viral; Virulent; analog; animal safety; cytokine; cytokine release syndrome; drug development; experimental study; improved; in vivo; inhibitor/antagonist; knock-down; lead optimization; mouse model; multidisciplinary; nanomolar; novel; pre-clinical; remdesivir; safety study; severe COVID-19; small molecule inhibitor; standard of care; synergism; virology

Our goal is to develop towards an IND a novel class of small molecule inhibitors of phosphoinositide (PI) 4 kinase IIIb (PI4KIIIb) with potent dual activity against both SARS-CoV-2 and the excess cytokine release associated with COVID-19 disease. Entry of SARS-CoV has been shown to depend on PI4KIIIb, and strong inhibition of entry was achieved following knockdown of PI4KIIIb via siRNA, and SARS-CoV-2 is believed to enter cells via a similar mechanism. This likely reflects a requirement for enrichment of phosphorylated isoforms of PI, such as PI-4, in the lipid organelle required for viral fusion upon entry. We have developed potent and specific small molecule inhibitors of PI4KIIIb, and optimized them for high oral bioavailability. Our lead inhibitor, STF-1019 has nanomolar efficacy against enteroviruses (EV) which are also dependent on PI4KIIIb, and is the only molecule to have demonstrated in vivo efficacy in the animal model of EV-71, and without toxicity. We have now shown that STF-1019’s EC50 against SARS-CoV-2 is 210 nM, with a CC50 of >100 microM, reflecting a therapeutic index (TI) of ~500. Finally, likely due to PI4KIIIb’s role in Golgi-mediated secretion, we have also recently shown that STF-1019 can potently inhibit the LPS-induced secretion of IL-6 from human PBMC. STF-1019’s metabolic stability, however, is suboptimal, requiring co-administration with an inhibitor (i.e. ritonavir) of its metabolism by CYP3A4 for optimal sustained tissue exposure. We hypothesize that: 1) STF-1019’s SAR and major metabolites indicates that our lead PI4KIIIb inhibitor can be further optimized to increase its activity and metabolic stability to achieve an optimal exposure profile; 2) modifications that further increase PI4KIIIb inhibition can provide a buffer for modifications that may increase metabolic stability at the expense of efficacy; 3) the optimized inhibitor will inhibit SARS-CoV-2 in vitro, and in vivo; 4) the optimized inhibitor will have a high barrier to the development of resistance; 5) because of its orthogonal mechanism of action, our PI4KIIIb inhibitor can be used in combination with other agents to maximize efficacy; 6) STF-1019’s inhibition of IL-6 reflects an ability to modulate the release of other cytokines, and this non- antiviral activity can be of great additional benefit in addressing the cytokine storm associated with severe COVID-19 infection; 7) determination of key pharmacokinetic, in vitro ADME-Tox parameters and initial preclinical in vivo toxicity assessment of our optimized lead can advance its translational development, and form the basis of a future IND package. We propose the test these hypotheses by: 1) Identifying the STF-1019 analog (and back-up compound) with greatest in vivo trough:EC90 ratios; 2) determining the in vivo activity of the optimized PI4KIIIb inhibitors against SARS-CoV-2 and their effect on cytokine production; 3) determining the relative barrier to resistance, and potential for synergy with other agents; and 4) nominating a PI4KIIIb inhibitor IND candidate by subjecting the optimized lead to initial in vitro ADME-tox and IND-enabling preclinical animal safety studies.

我们的目标是向IND发展一类新型的小分子抑制剂（PI）4 激酶IIIB（PI4KIIIB）具有对SARS-COV-2和过量细胞因子释放的潜在双重活性 与Covid-19疾病有关。已显示SARS-COV的进入取决于PI4KIIIB，并且很强 通过siRNA敲除PI4KIIIB后，可以抑制入口，并且据信SARS-COV-2 通过类似的机制进入细胞。这可能反映了富集磷酸化的要求 进入脂质细胞器中的PI的同工型在进入时需要进行病毒融合所需的脂质细胞器中。我们已经发展了 PI4KIIIB的有效和特定的小分子抑制剂，并优化了高口服生物利用度。我们的 铅抑制剂，STF-1019具有针对肠病毒（EV）的纳摩尔有效性，这也取决于 PI4KIIIB，是唯一在EV-71动物模型中证明体内效率的分子，并且 没有毒性。现在，我们已经表明，STF-1019对SARS-COV-2的EC50为210 nm，CC50为CC50 > 100 microm，反映了〜500的治疗指数（Ti）。最后，可能是由于PI4KIIIB在高尔基体介导的 分泌，我们最近还表明，STF-1019可能会抑制LPS诱导的IL-6分泌 来自人类PBMC。但是，STF-1019的代谢稳定性是次优的，需要与 CYP3A4代谢的抑制剂（即利托那韦），以实现最佳的持续组织暴露。我们假设 那是：1）STF-1019的SAR和主要代谢物表明我们的铅PI4KIIIB抑制剂可以进一步 优化以提高其活性和代谢稳定性，以实现最佳的暴露概况； 2）修改 进一步增加PI4KIIIB抑制可以为修改可能增加代谢提供缓冲 稳定以牺牲效率为代价； 3）优化的抑制剂将在体外和体内抑制SARS-COV-2； 4） 优化的抑制剂将对抗性发展具有很大的障碍； 5）由于其正交 作用机理，我们的PI4KIIIB抑制剂可以与其他药物结合使用以最大程度地提高效率。 6）STF-1019对IL-6的抑制反映了调节其他细胞因子释放的能力，而这种非 - 抗病毒活性在解决与严重相关的细胞因子风暴方面可能有很大的好处 2019冠状病毒病感染; 7）确定关键药代动力学，体外ADME-TOX参数和初始参数 临床前的体内毒性评估我们优化的铅可以提高其翻译发展，并 构成未来IND软件包的基础。我们提出了这些假设的测试：1）确定STF-1019 具有最大体内麻烦的模拟（和备用化合物）：EC90比率； 2）确定体内活性 针对SARS-COV-2的优化PI4KIIIB抑制剂及其对细胞因子产生的影响； 3）确定 抵抗性的相对障碍，以及与其他药物协同作用的潜力； 4）提名PI4KIIIB 抑制剂IND候选者通过对优化导致初始体外ADME-TOX和辅助候选者进行抑制剂IND候选者 临床前动物安全研究。