Cocrystal reports pan-viral inhibitors active against hantavirus and influenza

Cocrystal Pharma, Inc. (Nasdaq: COCP) announced on May 26, 2026 that its novel direct-acting antivirals demonstrate pan-viral activity against several viruses, including hantavirus, bunyavirus and influenza. The release says the molecules target a highly conserved region of the viral replication enzyme. Specifically, they target the L-protein of Andes hantavirus, which is essential for viral replication and transcription. The company describes its in vitro potency data as showing superior activity. The release text as filed shows no potency values, no comparison drug and no number of compounds tested, so "superior" cannot be checked. These are lab results from cells and enzymes, not studies in animals or people.

The discovery

In the release, President and co-Chief Executive Officer Sam Lee, Ph.D., says the company is developing the next generation of pan-viral replication inhibitors. He says the goal is a pan-viral lead molecule for multiple viral diseases caused by hantaviruses, bunyaviruses and influenza viruses. He adds: "We are encouraged by our initial in vitro potency data against hantavirus and plan to evaluate in vitro antiviral activity against the Andes hantavirus replication enzyme."

The release names CDI-988 as the company's first pan-viral protease inhibitor. It says CDI-988 recently advanced to a Phase 1b norovirus challenge study in the United States. The release does not say whether the new molecules are related to CDI-988, and it reports no results from that trial.

Why hantavirus

The release cites an outbreak of Andes hantavirus on a cruise ship that infected up to 11 passengers and crew and caused three deaths. It says hantaviruses are primarily transmitted by rodents, although human-to-human transmission can occur through prolonged close contact.

Andes hantavirus is endemic in Argentina and Chile. It causes hantavirus cardiopulmonary syndrome, which the release associates with a case fatality rate of up to 50%. The release states that there are no approved antivirals or vaccines for Andes hantavirus or other hantaviruses. An outbreak and an empty market are the company's reason for the work; they do not show the molecules will reach patients.

The company and its platform

Cocrystal describes itself as a clinical-stage biotechnology company discovering and developing novel antiviral therapeutics that target the replication process of noroviruses, influenza viruses, coronaviruses and hepatitis C viruses. The release says its platform provides a three-dimensional structure of inhibitor complexes at near-atomic resolution.

The company's annual report business section describes a proprietary platform that combines computational chemistry, medicinal chemistry and X-ray crystallography. It says the company has applied these techniques to develop antiviral inhibitors of influenza virus, coronavirus, norovirus and HCV. The business section also credits Dr. Roger Kornberg, Chief Scientist and Chairman of the Board, who received the Nobel Prize in Chemistry in 2006, with guiding the approach.

Financial position

The XBRL data in the annual report show research and development expense of $5.1 million for the year ended December 31, 2025, compared with $12.5 million for 2024. The net loss was $8.8 million in 2025, compared with $17.5 million in 2024. Cash used in operations was $8.2 million in 2025, compared with $16.5 million in 2024.

Cash and cash equivalents were $7.0 million at December 31, 2025, down from $9.9 million at December 31, 2024. That is less than the $8.2 million of cash used in operations in 2025. The release does not state a cash balance for any date in 2026, and its own risk language names the company's liquidity as a risk.

What comes next

The release says Cocrystal plans to evaluate in vitro antiviral activity against the Andes hantavirus replication enzyme. It also says the company looks forward to exploring collaborations and partnerships to address what it calls urgent unmet needs in hantavirus and bunyavirus. No dates are given for that work. The release's risk language also cites research on a related virus that was not done in animals and was early stage, possible resistance from mutations, and competitors' treatments financed by the U.S. government. A search for partners is a hope, not a deal: the release names no partner and no terms.

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