CMX990 for COVID-19

CMX990 may be beneficial for COVID-19 according to the studies below. COVID-19 involves the interplay of 500+ viral and host proteins and factors providing many therapeutic targets. Scientists have proposed 12,000+ potential treatments. c19early.org analyzes 220+ treatments. We have not reviewed CMX990 in detail.
Elshan et al., Discovery of CMX990: A Potent SARS-CoV-2 3CL Protease Inhibitor Bearing a Novel Covalent Warhead, bioRxiv, doi:10.1101/2023.10.24.563688
ABSTRACTThere 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 3CLproinhibitor, 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 humanin vitroclearance (>4x better microsomal clearance and >10x better hepatocyte clearance), with goodin vitro-in vivocorrelation. 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.
Elshan et al., Pan-Coronavirus Protease Engagement and Differentiated Pharmacology of Antiviral Candidate CMX990, bioRxiv, doi:10.64898/2026.09.29.755428
ABSTRACT COVID-19 highlighted the need for antivirals that can be rapidly deployed against both current and future coronavirus threats. CMX990 is a clinical stage coronavirus main protease (M pro ) inhibitor bearing a unique trifluoromethoxymethyl ketone warhead. Here, we broadly evaluate its pan-coronavirus target engagement, antiviral breadth, and pharmacologic differentiation. Across a reporter panel of 24 M pro enzymes spanning alpha-, beta-, delta-, and gamma-coronaviruses, CMX990 retained robust potent activity, including against nirmatrelvir-resistant SARS-CoV-2 variants. In direct comparison, nirmatrelvir and ensitrelvir showed diminished potency against non-SARS-CoV-2 coronaviruses. Live-virus assays corroborated this breadth, with potent, selective activity against SARS-CoV-2, SARS-CoV-1, MERS-CoV, and additional human coronaviruses. Structural studies revealed a conserved covalent binding mode centered on the catalytic Cys of coronavirus M pro . In serial-passage studies, resistance emerged only after approximately twice as many serial passages under CMX990 selection as under nirmatrelvir selection, without selecting for the canonical nirmatrelvir-resistance substitution E166V. Extracellular washout experiments revealed superior persistence of antiviral activity relative to nirmatrelvir, consistent with durable target engagement. In a murine SARS-CoV-2 infection model, once-daily CMX990 protected against weight loss and reduced lung viral titers to near baseline levels. Collectively, these findings identify CMX990 as a structurally and functionally validated pan-coronavirus protease inhibitor supporting its potential as a pandemic-ready antiviral candidate.
Nodola et al., Recent Advances in the Design of Inhibitors Targeting the Viral Entry and Replication of the SARS-CoV-2 Virus, Driven by In Silico Approaches, Molecules, doi:10.3390/molecules31162877
The SARS-CoV-2 pandemic has significantly impacted global health, politics, medicine, finance, and society. Since 2020, various mutations have been reported, leading to drug resistance in current treatments against different SARS-CoV-2 strains and a drastic increase in cases of long-COVID. This situation underscores the urgent need to develop targeted and effective drugs to combat the spread of SARS-CoV-2 strains and their mutants, manage long-COVID symptoms and prepare for future pandemics. Currently, the treatment of SARS-CoV-2 focuses on targeting the virus’s entry and replication mechanisms to disrupt its life cycle. This review examines approved drugs, clinical candidates, and inhibitors under development, along with their bioassay data, while highlighting associated challenges. It illustrates how inhibitors bind to active sites, providing insights and emphasizing the importance of in silico studies, such as molecular docking, molecular dynamics simulation, FEP+, WaterMap, and quantitative structure–activity relationship (QSAR) analyses, and their correlation with experimental studies in expediting the drug discovery process. The review aims to provide researchers with insights into the gaps that need to be addressed concerning mutations affecting viral entry and to prepare for future pandemics.