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Biology subjects

Elshan, N. G. R. D.

Publications and source records attributed to Elshan, N. G. R. D..

3 recordsLinked to original sources

Orally Bioavailable SARS-CoV-2 Protease Inhibitors Bearing a Hydroxymethyl Ketone Warhead

The use of covalent warheads targeting the catalytic cysteine has been a cornerstone in coronavirus main protease (Mpro) inhibitor development, where various electrophilic motifs have been used including aldehydes, nitriles, ketoamides, and hydroxymethyl ketones (HMKs). Recent efforts have been mostly centered around nitrile warheads, given the success of compounds like Nirmatrelvir and Ensitrelvir in the clinic. However, finding and advancing alternative chemotypes with differentiating chemical and pharmacological profiles is essential for future pandemic preparedness. Among such alternatives, HMKs hold special interest because they balance reduced intrinsic electrophilicity with an excellent selectivity profile. Nevertheless, early HMK-based compounds, such as the clinical-stage Mpro inhibitor PF-00835231, suffered from poor oral bioavailability and therefore required intravenous administration, with or without prodrug derivatization of the hydroxyl group. Here, we describe our efforts in advancing the HMK field via the discovery of mCMX110, a lead that has superior potency, increased unbound exposure in vivo, and favorable oral bioavailability in preclinical studies. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/725542v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@40222aorg.highwire.dtl.DTLVardef@831b88org.highwire.dtl.DTLVardef@184a910org.highwire.dtl.DTLVardef@779095_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Fubylation as a Druggable Ubiquitin-Like Conjugation System Controlling Hippo Pathway Activity

The functionally and evolutionarily conserved Hippo-YAP signaling pathway plays a critical role in regulating cellular proliferation, organ size control, and regeneration. Accordingly, activators of YAP-driven transcription hold therapeutic promise for treating disease states driven by insufficient proliferative repair, yet only a handful of pharmacological mechanisms exist for augmenting YAP activity. Here we report the discovery of sCMF231, a small molecule activator of YAP discovered from high throughput screening that acts by targeting the poorly characterized ubiquitin-like protein FUBI. Using canonical ubiquitin conjugation machinery--UBA1, UBE2C, and APC/C--FUBI covalently modifies the Hippo pathway protein Annexin A2, reinforcing its YAP suppressive role at the plasma membrane. Binding of sCMF231 to FUBI discourages its conjugation to Annexin A2, resulting in the membrane delocalization of Annexin A2 and a liberated, transcriptionally active form of YAP. This work provides the first definitive evidence of covalent modification of proteins by FUBI, a post-translational modification termed fubylation, and defines how fubylation regulates the activity of a central growth pathway.

biochemistry↗

Discovery of CMX990: A Potent SARS-CoV-2 3CL Protease Inhibitor Bearing a Novel Covalent Warhead

There remains a need to develop novel SARS-CoV-2 therapeutic options that improve upon existing therapies by increased robustness of response, fewer safety liabilities, and global-ready accessibility. Functionally critical viral main protease (Mpro, 3CLpro) of SARS-CoV-2 is an attractive target due to its homology within the coronaviral family, and lack thereof towards human proteases. In this disclosure, we outline the advent of a novel SARS-CoV-2 3CLpro inhibitor, CMX990, bearing an unprecedented trifluoromethoxymethyl ketone warhead. Compared with the marketed drug nirmatrelvir (combination with ritonavir = PaxlovidTM), CMX990 has distinctly differentiated potency ([~]5x more potent in primary cells) and human in vitro clearance (>4x better microsomal clearance and >10x better hepatocyte clearance), with good in vitro-in vivo correlation. Based on its compelling preclinical profile and projected once or twice a day dosing supporting unboosted oral therapy in humans, CMX990 advanced to a Phase 1 clinical trial as an oral drug candidate for SARS-CoV-2.

microbiology↗