FDA Authorizes First-in-Classโ Human Challenge Study for Oral Norovirus Antiviral
September 9, 2025 โ – โขThe โคFood and Drug โคAdministration hasโข cleared โCocrystal Pharma to proceed withโ a phase 1bโ human challenge study evaluating CDI-988, a potential oral antiviral drug for the โคprevention and treatment of norovirus. This marks a significant step toward developing the first antiviral โspecifically targeting the highly contagious virus.
Norovirus causes approximately 21 million infections annually in the United States, leading to over 100,000 hospitalizations and nearly 900โค deaths each year.The virus spreads easily through contaminatedโข food, surfaces, and close โcontact, โposing a particularโข risk to โฃimmunocompromised individuals, โขinfants, and older adults, who can remainโ contagious for weeks after recovering.
Preclinical studies haveโ demonstrated CDI-988’s broad antiviral activity, and initial phase 1 testing indicated theโฃ drug โคwas well-tolerated. The upcoming challenge study will assess โits efficacy in preventing โคor โtreating norovirus infection.
“This milestoneโฃ marks an significant step in advancing CDI-988 into clinical development,” said Sam Lee, โPhD, president and co-CEO of Cocrystal โPharma. “The planned challenge study will โhelp determine โขits efficacy โขin preventing or treating norovirus infection.”
Cocrystal โฃutilizes a structure-based drug โขdiscovery โฃplatform,โ enabling detailed modeling of drug-target interactionsโค to design โnovel antivirals. Beyond norovirus, โคCDI-988โ has also shown activity againstโ coronaviruses and is currently under investigation asโ a potential โCOVID-19 therapy, having received approval from the Australian โHuman Research Ethicsโค Committee โ(HREC) to โinitiate a phase I trial in 2023.
References
Cocrystal Pharma Receives FDAโ IND Clearance โfor Challenge Studyโ of Oral Broad-Spectrum Protease Inhibitorโ CDI-988, a โขPotential โFirst Antiviral for Norovirus Prevention and Treatment. BioSpace. September 9,2025. Accessed September 9, 2025. โhttps://www.biospace.com/press-releases/cocrystal-pharma-receives-fda-ind-clearance-for-challenge-study-of-oral-broad-spectrum-protease-inhibitor-cdi-988-a-potential-first-antiviral-for-norovirus-prevention-and-treatment?utmsource=chatgpt.com
Cocrystal Pharma’s norovirus antiviralโค study receivesโ FDAโ clearance. ClinicalTrialsArena. September 9, 2025. Accessedโ September โ9, 2025. https://www.clinicaltrialsarena.com/news/cocrystal-norovirus-study/?utmsource=chatgpt.com&cf-view
