JUN12682 for COVID-19

JUN12682 may be beneficial for COVID-19 according to the studies below. COVID-19 involves the interplay of 400+ viral and host proteins and factors providing many therapeutic targets. Scientists have proposed 11,000+ potential treatments. c19early.org analyzes 210+ treatments. We have not reviewed JUN12682 in detail.
Wang et al., Structural Basis and Inhibitor Development of SARS-CoV-2 Papain-like Protease, Molecules, doi:10.3390/molecules31030474
Papain-like protease (PLpro), a crucial functional domain of the SARS-CoV-2 non-structural protein 3 (nsp3), plays a dual role in both hydrolyzing viral polyprotein precursors and modulating host immune responses. These critical functions position PLpro as a key target in the ongoing development of antiviral therapies for SARS-CoV-2. This review analyzes more than 100 PLpro-ligand co-crystal structures and summarizes the major binding modes between these ligands and PLpro. Most of these ligands bind to sites analogous to those targeted by the classical non-covalent inhibitor GRL0617, primarily involving the P3 and P4 subsites and the BL2 loop. Based on these structural insights, optimized inhibitors have expanded targeting beyond the canonical binding site to auxiliary regions such as the BL2 groove and the Val70 site, and in some cases toward the catalytic Cys111 buried within a narrow pocket. Certain ligands identified through various screening approaches bind to non-canonical or allosteric regions, such as the S1 and S2 sites or the zinc-finger domain, engaging PLpro through distinct interaction modes and thereby offering additional opportunities for PLpro inhibitor design. The review also discusses potential strategies for future PLpro inhibitor development informed by recent structural advances. Taken together, these structural and functional insights support ongoing efforts in the structure-guided design and optimization of PLpro inhibitors.
Wu et al., Divergent resistance pathways amongst SARS-CoV-2 PLpro inhibitors highlight the need for scaffold diversity, PLOS Pathogens, doi:10.1371/journal.ppat.1013468
Drug-escape, where a target evolves to escape inhibition from a drug, has the potential to lead to cross-resistance where drugs that are structurally related or share similar binding mechanisms all become less effective. PLpro inhibitors are currently under development and many emerging PLpro inhibitors are derived from GRL0617, a repurposed SARS-CoV PLpro inhibitor with moderate activity against SARS-CoV-2. Two leading derivatives, PF-07957472 and Jun12682, demonstrate low nanomolar activity and display activity in mice. WEHI-P8 is structurally distinct but binds to a similar pocket adjacent to the active site as GRL0617-like compounds. Using deep mutational scanning, we assessed the potential for PLpro to develop resistance to PF-07957472, Jun12682, and WEHI-P8. PF-07957472 and Jun12682 exhibited largely overlapping escape mutations due to their shared scaffold and binding modes, whereas WEHI-P8 resistance mutations were distinct. These findings underscore the importance of developing structurally diverse inhibitors to minimize resistance risks and ensure that viral mutations against one compound do not compromise the efficacy of others.
Tan et al., Design of SARS-CoV-2 papain-like protease inhibitor with antiviral efficacy in a mouse model, bioRxiv, doi:10.1101/2023.12.01.569653
AbstractThe emergence of SARS-CoV-2 variants and drug-resistant mutants calls for additional oral antivirals. The SARS-CoV-2 papain-like protease (PLpro) is a promising but challenging drug target. In this study, we designed and synthesized 85 noncovalent PLproinhibitors that bind to the newly discovered Val70Ubsite and the known BL2 groove pocket. Potent compounds inhibited PLprowith inhibitory constant Kivalues from 13.2 to 88.2 nM. The co-crystal structures of PLprowith eight leads revealed their interaction modes. Thein vivoleadJun12682inhibited SARS-CoV-2 and its variants, including nirmatrelvir-resistant strains with EC50from 0.44 to 2.02 µM. Oral treatment withJun12682significantly improved survival and reduced lung viral loads and lesions in a SARS-CoV-2 infection mouse model, suggesting PLproinhibitors are promising oral SARS-CoV-2 antiviral candidates.One-Sentence SummaryStructure-guided design of SARS-CoV-2 PLproinhibitors within vivoantiviral efficacy in a mouse model.