Nirmatrelvir

FLORHAM PARK, N.J.--(BUSINESS WIRE)--Shionogi Inc., a New Jersey-based subsidiary of Shionogi & Co., Ltd., (Head Office: Osaka, Japan; Chief Executive Officer: Isao Teshirogi, PhD; hereinafter “Shionogi”) announced U.S. availability of XOCOVA® (ensitrelvir), an oral antiviral, approved for post-exposure prophylaxis (PEP) of COVID‑19 in adults and adolescents 12 years of age and older following contact with an individual who has COVID-19.2 XOCOVA offers a new approach to help prevent COVID-19 by blocking viral replication during the critical window between exposure and COVID-19 symptom onset.4,5 XOCOVA is taken once daily, with three 125 mg tablets (375 mg) taken at the same time on the first day, followed by one 125 mg tablet on days two through five. XOCOVA should be taken as soon as possible and within 72 hours following contact with an individual who has COVID‑19.1 “With XOCOVA, we have a novel oral option to help prevent COVID-19 after exposure, and it is available just in time for the annual late summer spike,” said Charles Vega, MD, FAAFP, Health Sciences Clinical Professor, University of California, Irvine, School of Medicine. “Taking XOCOVA to help prevent COVID-19 in the critical window between exposure and symptom onset makes sense for anyone who wants to try to avoid illness, and it could be especially beneficial for older adults and individuals with health conditions that may put them at higher risk for severe illness. Now, in addition to recommending my patients stay updated with vaccinations, I’ll be talking to them about XOCOVA, so they are ready to act quickly in the event of an exposure.” The U.S. has experienced a COVID-19 summer spike every year since 2020.3 Biobot Analytics, a wastewater intelligence company with continuous and longitudinal data on pathogens from wastewater, reports that SARS-CoV-2 levels are beginning to rise, providing an early, population-level signal that another COVID-19 summer wave may be taking shape.6 Scenario modeling from The U.S. Centers for Disease Control and Prevention indicates there may be increased COVID-19 activity in regions (South and West) which did not experience a substantial level of COVID-19 activity during the most recent fall and winter months.3 “Post-exposure prophylaxis, or PEP for short, has been used successfully with influenza as well as HIV and other sexually transmitted infections, and it has the potential to help reduce the burden of COVID-19,” said David Wohl, MD, Professor of Medicine, The University of North Carolina at Chapel Hill, School of Medicine. “The availability of XOCOVA means that now, for the first time, there’s an oral option that can help prevent COVID-19 after exposure. Since XOCOVA must be taken within 72 hours of exposure, having it on hand can help ensure it is taken within the critical window between exposure and COVID-19 symptom onset.” Having XOCOVA on hand can help appropriate patients be prepared in the event of a COVID-19 exposure. Before taking XOCOVA, individuals should review the dosing and administration instructions and check the expiration date on the blister pack. They should also speak with a healthcare professional if there are any changes to their medications (including prescription and over-the-counter medicines), vitamins or supplements and verify they are not pregnant or breastfeeding. Shionogi is supporting the availability of XOCOVA through professional and consumer education and partnerships with national and regional pharmacies to ensure product availability. Select retail pharmacies across the U.S. will have XOCOVA in stock, and all retail pharmacies can order it from Shionogi’s wholesale distribution partners. Shionogi has a commercial co-pay offer for XOCOVA that helps eligible, commercially insured patients with out-of-pocket costs. Eligible patients may pay as little as $0 per prescription fill. Details about eligibility are available at https://www.xocova.com/. All components of XOCOVA are produced in the U.S. including active pharmaceutical ingredient production, drug product formulation, packaging, quality control, release testing, and supply chain and distribution. The Ongoing Impact of COVID-19 COVID-19 remains highly transmissible, driven by Omicron and its subvariants, and up to 47% of people living with an infected individual may develop COVID-19.7 The U.S. Centers for Disease Control and Prevention estimates that between October 1, 2025, and July 11, 2026, there were 4.2-12.7 million new cases in the U.S., resulting in 840,000 – 2.3 million outpatient visits, 130,000 – 250,000 hospitalizations and 14,000 - 42,000 deaths.8 Beyond acute infection, COVID-19 can have lasting impacts. People diagnosed with COVID-19 had increased rates of both new and worsening neurologic, cardiovascular, respiratory, and chronic kidney conditions during the year following infection.9-,10,11,12,13,14,15,16,17,18 COVID-19 also disproportionately affects older adults with greater risk for severe illness and death in close-community settings, such as long-term care facilities.19 About SCORPIO-PEP The global, double-blind, randomized, placebo-controlled Phase 3 study, SCORPIO-PEP, assessed the safety and efficacy of XOCOVA as post-exposure prophylaxis for COVID-19. The study was conducted from June 2023–September 2024. It included 2,387 study participants aged 12 years and older with a negative local screening test for SARS-CoV-2 infection and no symptoms at the time of enrollment, who were exposed to a person living in their household with symptomatic COVID-19. The primary analysis included 2,041 household contact participants with a central laboratory-confirmed negative SARS-CoV-2 test at baseline. More than 98% of household contacts tested positive for antibodies against SARS-CoV-2 N (nucleocapsid) or S (spike) proteins, indicating that nearly all had evidence of previous SARS-CoV-2 infection or vaccination, or both.20 Study participants were randomly assigned at a 1:1 ratio to receive XOCOVA (375 mg on Day 1 and 125 mg on Days 2-5) or placebo, once daily, and began treatment within 72 hours of when the household member with COVID-19 began showing symptoms. Participants then continued XOCOVA (125 mg) or placebo for five days. In the primary analysis population, XOCOVA significantly reduced the risk of symptomatic COVID-19 by 67% in individuals following exposure to an infected individual through Day 10 compared with placebo (ensitrelvir n=1,030; placebo n=1,011).2 The most common adverse events (regardless of causality) occurring in greater than or equal to 1% of the XOCOVA group and at a greater frequency compared to placebo were headache, diarrhea, and cough.1 There were no reports of altered taste (dysgeusia) attributed to XOCOVA in the trial.2,20 Results from the SCORPIO-PEP trial were published in the New England Journal of Medicine on May 14, 2026. SCORPIO-PEP is the first and only Phase 3 study of an oral antiviral to meet the primary endpoint of preventing COVID-19 following exposure to an infected individual. About XOCOVA XOCOVA® (ensitrelvir) is a SARS-CoV-2 main protease inhibitor created through joint research between Hokkaido University and Shionogi. SARS-CoV-2 has an enzyme called the main protease, which is essential for the replication of the virus. XOCOVA suppresses the replication of SARS-CoV-2 by selectively inhibiting the main protease. XOCOVA is approved in the U.S. and Japan for post-exposure prophylaxis of COVID‑19 in adults and adolescents 12 years of age and older following contact with an individual who has COVID-19. XOCOVA received emergency regulatory approval in Japan in November 2022 and full approval in March 2024 for the treatment of COVID-19 in adults and adolescents 12 years of age and older based on results from SCORPIO-SR, a Phase 3 study conducted in Asia during the Omicron-dominant phase of the pandemic. Results from this study were published in JAMA Network Open. XOCOVA received supplemental approval in June 2026 in Japan for pediatric patients aged 6 to under 12 years who weigh at least 20 kg for the treatment of COVID-19. XOCOVA is not approved for the treatment of COVID-19 in the U.S. INDICATION XOCOVA (ensitrelvir) is a prescription medicine used to help prevent coronavirus disease 2019 (COVID-19) in adults and children aged 12 years and older following contact with a person who has COVID-19 (post-exposure prophylaxis). It is not known if XOCOVA is safe and effective in children under age 12. IMPORTANT SAFETY INFORMATION Do not take XOCOVA if you are: allergic to ensitrelvir or any of the ingredients in XOCOVA. take any of the following medicines, as these may interact with XOCOVA and may cause severe or life-threatening side effects or death: apalutamide, carbamazepine, colchicine, dihydroergotamine, enzalutamide, eplerenone, ergotamine, finerenone, ivabradine, lomitapide, lumacaftor/ivacaftor, lurasidone, methylergonovine, phenytoin, pimozide, quinidine, rifampin, St. John’s wort, simvastatin, triazolam or voclosporin. These are not the only medicines that may cause serious or life-threatening side effects if taken with XOCOVA. XOCOVA may increase or decrease the levels of many medicines in your body. Tell your healthcare provider (HCP) about all the medicines you take because additional laboratory tests or dose changes of your other medicines may be necessary during XOCOVA use. Your HCP may tell you about specific symptoms to watch for that may indicate you need to stop or decrease the dose of some of your other medicines. Before taking XOCOVA, tell your HCP about all your medical conditions, including if you: are pregnant or plan to become pregnant. XOCOVA may harm your unborn baby. For females who are able to become pregnant, your HCP will check with you to see if you are pregnant before starting XOCOVA. Use effective birth control (contraception) during XOCOVA use and for 2 weeks after the final dose. Tell your HCP right away if you become pregnant or think you may be pregnant during XOCOVA use. are breastfeeding or plan to breastfeed. It is not known if XOCOVA passes into your breast milk. Do not breastfeed during XOCOVA use and for 2 weeks after the final dose. Tell your HCP about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Your HCP can tell you if it is safe to take XOCOVA with other medicines. Do not start a new medicine without telling your HCP. What are the possible side effects of XOCOVA? XOCOVA may cause serious side effects, including: Allergic reactions, including severe allergic reactions (anaphylaxis). Stop taking XOCOVA and get medical help right away if you get any of the following allergic reaction symptoms: skin rash; hives; itching; swelling of the mouth, lips, tongue, or face; trouble swallowing or breathing; throat tightness; dizziness or feeling lightheaded; stomach-area (abdomen) pain; or vomiting. The most common side effects of XOCOVA include: headache, diarrhea, and cough. These are not all possible side effects of XOCOVA. For more info, ask your HCP or pharmacist. You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.fda.gov/medwatch or call 1-800-FDA-1088. Please see full Prescribing Information, including Patient Information, for XOCOVA. About Shionogi Inc. Shionogi Inc. is a U.S. subsidiary of Shionogi & Co., Ltd., a global research‑driven pharmaceutical company committed to bringing to market the best possible medicines to aid the health and well-being of the patients we serve. Our global expertise in infectious disease began in the 1950s and in addition to discovering and developing multiple innovative antibiotics, today our global portfolio includes an antibiotic for the treatment of serious Gram‑negative bacterial infections, antivirals for COVID-19, HIV and influenza and a therapeutic for rare fungal infections. Our U.S. infectious disease franchise includes both approved and investigational novel anti-infectives, and investigational antivirals for COVID-19 and RSV. In parallel, we are advancing a U.S. rare disease franchise that includes an approved therapy for amyotrophic lateral sclerosis (ALS), along with clinical programs in Fragile X syndrome, Jordan’s syndrome, and Pompe disease. We are also pursuing research in additional high‑unmet need therapeutic areas, including oncology, acute ischemic stroke, sleep apnea, and other quality of life areas. Learn more at shionogi.com. About Shionogi & Co., Ltd. Shionogi & Co., Ltd. is a 148-year-old global, research-driven pharmaceutical company headquartered in Osaka, Japan, that is dedicated to bringing benefits to patients based on its corporate philosophy of “supplying the best possible medicine to protect the health and wellbeing of the patients we serve.” The company currently markets products in several therapeutic areas including anti-infectives, pain, CNS disorders and cardiovascular diseases. Shionogi’s research and development currently targets two therapeutic areas: infectious diseases and diseases with unmet medical needs in pain/CNS, including Alzheimer’s disease, oncology, rare diseases, and sleep apnea. For more information on Shionogi & Co., Ltd., please visit https://www.shionogi.com/global/en. Forward-Looking Statements This announcement contains forward-looking statements. These statements are based on expectations in light of the information currently available, assumptions that are subject to risks and uncertainties which could cause actual results to differ materially from these statements. Risks and uncertainties include general domestic and international economic conditions such as general industry and market conditions, and changes of interest rate and currency exchange rate. These risks and uncertainties particularly apply with respect to product-related forward-looking statements. Product risks and uncertainties include, but are not limited to, completion and discontinuation of clinical trials; obtaining regulatory approvals; claims and concerns about product safety and efficacy; technological advances; adverse outcome of important litigation; domestic and foreign healthcare reforms and changes of laws and regulations. Also for existing products, there are manufacturing and marketing risks, which include, but are not limited to, inability to build production capacity to meet demand, lack of availability of raw materials and entry of competitive products. The company disclaims any intention or obligation to update or revise any forward-looking statements whether as a result of new information, future events or otherwise. *Literature search conducted in May 2026 1 XOCOVA (ensitrelvir) Prescribing Information. Available from: https://www.shionogi.com/content/dam/shionogi/si/products/pdf/xocova.pdf. Accessed July 6, 2026. 2 Hayden FG, Shinkai M, et al. Ensitrelvir for COVID-19 postexposure prophylaxis in household contacts. N Engl J Med. 2026;394(19):1905-1915. doi:10.1056/NEJMoa2509306. 3 Centers for Disease Control and Prevention [Internet]. 2026 COVID-19 Summer Outlook. 2026. Available from: https://www.cdc.gov/cfa-qualitative-assessments/php/data-research/2026covid-19outlook.html 4 Kawashima S, Matsui Y, et al. Ensitrelvir is effective against SARS-CoV-2 3CL protease mutants circulating globally. Biochem Biophys Res Commun. 2023;645:132-136. doi:10.1016/j.bbrc.2023.01.040. 5 Kuroda T, Nobori H, et al. Efficacy comparison of 3CL protease inhibitors ensitrelvir and nirmatrelvir against SARS-CoV-2 in vitro and in vivo. J Antimicrob Chemother. 2023;78(4):946-952. doi:10.1093/jac/dkad027. 6 Donnelly M [Internet]. Respiratory risk report: week ending in July 4, 2026. Biobot Analytics; 2026. Available from: https://biobotanalytics.substack.com/p/respiratory-risk-report-663 7 Tanaka M, Ruiz C, et al. SARS-CoV-2 transmission dynamics in households with children, Los Angeles, California. Front Pediatr. 2021;9:752993. doi:10.3389/fped.2021.752993. 8 Centers for Disease Control and Prevention [Internet]. Preliminary estimates of COVID-19 burden for 2024-2025. 2026. Available from: https://www.cdc.gov/covid/php/surveillance/burden-estimates.html 9 Centers for Disease Control and Prevention [Internet]. Long COVID basics. 2026. Available from: https://www.cdc.gov/long-covid/about/index.html. 10 Xie Y, Xu E, et al. Long-term cardiovascular outcomes of COVID-19. Nat Med. 2022;28(3):583-590. doi:10.1038/s41591-022-01689-3. 11 Xie Y, Xu E, et al. Risks of mental health outcomes in people with COVID-19: a cohort study. BMJ. 2022;376:e068993. doi:10.1136/bmj-2021-068993. 12 Srivastava S, Garg I. Post-COVID-19 infection: long-term effects on liver and kidneys. World J Meta-Anal. 2021;9(3):220-233. doi:10.13105/wjma.v9.i3.220. 13 Tenforde MW, Kim SS, et al. Symptom duration and risk factors for delayed return to usual health among outpatients with COVID-19 in a multistate health care systems network— United States, March-June 2020. MMWR Morb Mortal Wkly Rep. 2020;69(30):993-998. doi:10.15585/mmwr.mm6930e1. 14 Graham EL, Clark JR, et al. Persistent neurologic symptoms and cognitive dysfunction in non-hospitalized COVID-19 “long haulers.” Ann Clin Transl Neurol. 2021;8(5):1073-1085. doi:10.1002/acn3.51350. 15 Kwok WC, Chau CH, et al. Outcomes among patients with chronic obstructive pulmonary disease after recovery from COVID-19 infection of different severity. Sci Rep. 2024;14(1):13881. doi:10.1038/s41598-024-64670-9. 16 Conway SE, Healy BC, et al. COVID-19 severity is associated with worsened neurological outcomes in multiple sclerosis and related disorders. Mult Scler Relat Disord. 2022;63:103946. doi:10.1016/j.msard.2022.103946. 17 Chen IW, Chang LC, et al. Association between COVID-19 and the development of chronic kidney disease in patients without initial acute kidney injury. Sci Rep. 2025;15(1):10924. doi:10.1038/s41598-025-96032-4. 18 Sax PE, Draica F, et al. New onset conditions, exacerbations and worsening of underlying conditions following COVID-19 infection [poster presentation]. Presented at: Conference on Retroviruses and Opportunistic Infections (CROI); 2026; Denver, CO, United States. 19 Gravenstein S, Cooke C, et al. Current impact of COVID-19 in long-term care facilities in the United States: a systematic literature review [poster presentation]. Presented at: Conference on Retroviruses and Opportunistic Infections (CROI); 2026; Denver, CO, United States. 20 Hayden FG, Shinkai M, et al. Ensitrelvir for COVID-19 postexposure prophylaxis in household contacts. Supplementary Appendix. N Engl J Med. 2026;394(19). Available from: https://www.nejm.org/doi/suppl/10.1056/NEJMoa2509306/suppl_file/nejmoa2509306_appendix.pdf.

Oral presentation unifies the respiratory and hepatic programs. The first-in-class, direct-acting, broad-spectrum, Thumb-1 polymerase inhibitor demonstrates single-agent activity against influenza, RSV, SARS-CoV-2, HCV, HBV, and HDV, including activity against oseltamivir-resistant influenza and oral in vivo proof-of-concept. SAN DIEGO — Model Medicines , an AI-first biotechnology company developing first-in-class therapeutics against multi-indication biological choke points, today announced that it will present new preclinical data at the 45th Annual Meeting of the American Society for Virology ( ASV 2026 ), to be held July 27–30, 2026, on the University of Minnesota Twin Cities campus in Minneapolis, MN. The event is being supported by Gilead Sciences Foundation, Elanco, GSK, Roche, Moderna, and Cocrystal Pharma, among others. The oral presentation will be delivered by Daniel Haders, PhD, Founder and CEO of Model Medicines. The data advance MDL-001 toward two first-in-class therapeutic goals: a universal direct-acting antiviral for influenza-like illness (influenza, RSV, and coronaviruses) and a universal direct-acting antiviral for chronic hepatitis (hepatitis C, hepatitis B, and hepatitis D). The ASV presentation is the first to report both goals as a single cross-family dataset. ASV 2026 Oral Presentation Presenter: Daniel Haders, PhD, Founder and CEO, Model Medicines Title: MDL-001, an oral Thumb-1 polymerase inhibitor, demonstrates broad-spectrum antiviral activity across six viral families with oral in vivo proof-of-concept Workshop: W44 — Antiviral Therapies II Program Number: W44-3 Abstract ID: 4518354 Date: July 29, 2026 Time: 7:00–7:15 PM CT (workshop session: 6:30–8:00 PM CT) Location: Room PWB 2-470, Phillips-Wangensteen Building Authors: Daniel Haders, Virgil Woods, Tyler Umansky, Sean Russell, Asha Goodman, Michael Bobardt, Briana McGovern, Kris M. White, Adolfo García-Sastre, William Brubaker, Philippe Gallay, Davey Smith Affiliations: Model Medicines; Scripps Research; Icahn School of Medicine at Mount Sinai; Farmington Pharma Development; University of California, San Diego. Each winter, clinicians face a recurring tripledemic of influenza, RSV, and SARS-CoV-2 that imposes hundreds of millions of infections and hundreds of thousands of deaths worldwide every year. [1] In a non-pandemic year in the U.S. alone, adults experience two to six of these respiratory viral illnesses and children approximately six to eight, at an economic cost exceeding $100 billion. [2] , [3] Despite this recurring toll, no single-agent antiviral is approved to treat the annual convergence of the tripledemic, and the world is no better prepared for the next respiratory pandemic than it was for the last. Chronic viral hepatitis is a health crisis of comparable scale. Hepatitis B and C infections persist in 254 million and 58 million people worldwide, respectively. [4] An estimated 5–15 million carry both viruses at once, yet most will never be diagnosed. Only 13% of HBV infections and 36% of HCV infections are identified globally, and fewer than 1% of co-infected patients know their status. Co-infection is not merely additive. Patients carrying both viruses are over 100-fold more likely to develop hepatocellular carcinoma than uninfected individuals. [5] Compounding the danger, every FDA-approved HCV direct-acting antiviral (DAA) carries a boxed warning for the risk of hepatitis B virus (HBV) reactivation in patients with current or prior HBV infection. This reactivation can lead to fulminant hepatitis, liver failure, or death. This FDA-mandated warning, added in 2016, applies to all DAA regimens, such as Epclusa, Harvoni, Mavyret, and others. Together, these gaps point to a single, persistent, and largely unaddressed need: one oral agent with broad-spectrum, direct-acting activity across the RNA viruses that drive both crises. For forty years, that molecule has been considered impossible to build. MDL-001 is designed to meet that need. It is the first direct-acting, non-nucleoside antiviral shown to be potent across multiple RNA virus families, and the first therapeutic of any mechanism to match or exceed multiple approved standards of care across RNA virus families in preclinical models. Its activity across both acute respiratory and chronic hepatic infection, combined with oral bioavailability, favorable pharmacokinetics, and a clean preclinical safety profile, positions the compound as a potential first-in-class therapy that could collapse multiple fragmented treatment paradigms into one. Model Medicines has reported the respiratory and hepatic arms of the MDL-001 program separately over the past year at IDWeek 2025 [6] , AASLD 2025 [7] , HepDART 2025 [8] , CROI 2026 [9] , ESCMID Global 2026 [10] , SERVC 2026 [11] and EASL 2026 [12] . “MDL-001 is the first Thumb-1 inhibitor to demonstrate antiviral activity across six viral families,” said Daniel Haders, PhD, Founder and CEO of Model Medicines. “The field held that allosteric pockets on viral polymerases diverge too rapidly to support cross-family targeting. Our work shows the RdRp Thumb-1 pocket is conserved and cryptic, and that the right chemistry engages it across families. ASV convenes the virologists best equipped to interrogate that claim, and we look forward to the discussion in Minneapolis.” The American Society for Virology is the largest virology society in the world. ASV meetings are among the largest and most important virology conferences globally, providing a forum for discussion and collaboration among scientists working across all aspects of virology, from basic research to vaccines and antiviral therapeutics. Program details are available at . About the Target: RdRp Thumb-1, A Conserved and Druggable Allosteric Target Conventional scientific wisdom holds that allosteric sites on viral polymerases diverge too rapidly to enable broad-spectrum direct-acting antiviral (DAA) development. Model Medicines overturned this assumption by demonstrating the structural conservation of the RNA-dependent RNA polymerase (RdRp) Thumb-1 allosteric pocket across viral families. The Thumb-1 site governs an essential mechanism for viral replication. The Thumb-1 pocket interacts with the viral Λ1-loop to control an indispensable conformational change required for polymerase initiation. Viruses cannot abandon this mechanism without sacrificing their replicative fitness. This target discovery is the biological foundation for Model Medicines’ Virology Program. Data on RdRp Thumb-1 can be found here . The corresponding preprint can be found here . About MDL-001: Discovery and Preclinical Profile Model Medicines utilized its AI-driven GALILEO™ platform to discover novel broad-spectrum inhibitor chemistry for this target within a multi-scaffold Markush structure. The research team trained GALILEO™ on a proprietary dataset spanning multiple viral families. This training enabled the model to learn the structural and chemical features required for broad-spectrum Thumb-1 inhibition. A library of potent inhibitors has been discovered, reduced to practice, and validated. Specifically, MDL-001 is the first DAA shown to be potent against multiple viral families in vitro: Orthomyxoviridae, Pneumoviridae, Coronaviridae, Flaviviridae, Kolmioviridae, and Hepadnaviridae. MDL-001 has demonstrated multi-log antiviral efficacy against influenza, SARS-CoV-2, HCV, and HBV in animal models. Furthermore, in vivo results demonstrate superiority or equivalence to multiple standards of care, including sofosbuvir, oseltamivir, remdesivir, and nirmatrelvir. Model Medicines plans to Investigational New Drug (IND) application with the FDA for MDL-001 in 2027. The full preclinical data readout can be found here . The corresponding preprint can be found here . About GALILEO™ GALILEO™ is Model Medicines’ proprietary, peer-reviewed, end-to-end multimodal generative AI drug discovery platform designed to discover and de-risk therapeutics against challenging and "undruggable" biological targets. Powered by Built-for-Purpose datasets and an ensemble of generative AI and zero-shot models, GALILEO™ integrates target discovery, tera-scale ultra-large virtual screening, ADMET prediction, compound synthesis, and automated lead optimization. By leveraging 3D protein structure data and strict chemical novelty metrics, the platform enables early, high-confidence compound prioritization with industry-leading prospective hit rates and exceptional chemical novelty. GALILEO™ powers Model Medicines' internal pipeline, including lead candidates MDL-001 and MDL-4102. The platform was validated through peer-reviewed publication in the American Chemical Society (ACS) journal Chemical Research in Toxicology. About Model Medicines Model Medicines is an AI-first biotechnology company engineering first-in-class small molecules that target the biological linchpins underlying disease. The company’s research spans infectious disease, oncology, and inflammation, with programs designed around conserved molecular choke points that drive multiple pathologies. Model Medicines has discovered a direct-acting, non-nucleoside, broad-spectrum antiviral (MDL-001) and a potent, selective, and novel BRD4 inhibitor (MDL-4102). Its work demonstrates how large-scale computation can uncover entirely new classes of drugs once thought unreachable. Model Medicines is advancing a new generation of therapeutics that redefine what is possible in modern drug discovery. Learn more at . Media Contact Patrick O’Neill Head of Partnerships & Investor Relations media@modelmedicines.com [1] Luong QXT, Hoang PT, Ho PT, Ayun RQ, Lee TK, Lee S. Potential broad-spectrum antiviral agents: a key arsenal against newly emerging and reemerging respiratory RNA viruses. Int J Mol Sci. 2025;26:1481. [2] Rossignol JF. Rethinking methods used to evaluate effectiveness of therapeutics for COVID-19 and other viral respiratory illnesses. Future Virol. 2022;17:67-69. [3] Hanage, W. P., & Schaffner, W. (2025). Burden of Acute Respiratory Infections Caused by Influenza Virus, Respiratory Syncytial Virus, and SARS-CoV-2 with Consideration of Older Adults: A Narrative Review. Infectious diseases and therapy, 14(Suppl 1), 5–37. [4] World Health Organization. Global hepatitis report 2024: action for access in low- and middle-income countries. Geneva: WHO; 2024. [5] Mavilia MG, Wu GY. HBV-HCV coinfection: viral interactions, management, and viral reactivation. J Clin Transl Hepatol. 2018;6:296-305. [6] MDL-001: A Broad-Spectrum Antiviral Targeting the Thumb-1 Domain of Viral Polymerases, Open Forum Infectious Diseases, Volume 13, Issue Supplement_1, January 2026, ofaf695.084, [7] MDL-001 As A Next Generation HCV Thumb-1 inhibitor With Clinical-Stage Safety, The Liver Meeting: 2025 Abstracts. (2025). Hepatology (Baltimore, Md.), 82(S1), S1–S2308. Abstract 0088. [8] Oral Thumb-1 polymerase inhibitor MDL-001 achieves preclinical HCV and HBV proof-of-concept, including HCV/HBV co-infection and equivalence to sofosbuvir. Paper presented at: HEPDART 2025; December 7–11, 2025 . [9] MDL-001, a novel oral thumb-1 polymerase inhibitor, shows efficacy in HCV/HBV in vitro and in vivo. Paper presented at: Conference on Retroviruses and Opportunistic Infections (CROI); February 22–25, 2026; Denver, CO. Abstract 589. [10] MDL-001, an oral direct-acting Thumb-1 polymerase inhibitor, demonstrates broad-spectrum activity against influenza viruses, respiratory syncytial virus, and SARS-CoV-2 with oral proof-of-concept in mice. Abstract presented at: ESCMID Global 2026; April 18, 2026; Munich, Germany. Abstract 5803 . MDL-001, an oral direct-acting Thumb-1 polymerase inhibitor, demonstrates single-agent efficacy against HCV/HBV co-infection in vitro, and achieves HCV and HBV preclinical proof-of-concept. Abstract presented at: ESCMID Global 2026; April 18, 2026; Munich, Germany. Abstract 5778. [11] MDL-001, an oral direct-acting Thumb-1 polymerase inhibitor, demonstrates broad-spectrum activity against influenza viruses, respiratory syncytial virus, and SARS-CoV-2 with oral proof-of-concept in mice. Paper presented at: The 18th Southeastern Regional Virology Conference (SERVC 2026), April 24–26, 2026 [12] MDL-001, an oral direct-acting Thumb-1 polymerase inhibitor, demonstrates efficacy against HCV/HBV co-infection in vitro, and achieves HCV and HBV preclinical proof-of-concept, including equivalence to sofosbuvir, Journal of Hepatology, Volume 84, Supplement 1, May 2026, Pages S877-S878, THU-580. (26)02352-4/abstract