Norovirus

Norovirus is highly contagious and causes symptoms such as nausea, vomiting, stomach pain, diarrhea, fatigue, fever and dehydration. It is notorious for its occurrence in closed environments including military settings, hospitals, nursing homes, childcare facilities and cruise ships.

With an estimated 685 million global cases annually and a $60 billion worldwide economic impact, norovirus represents one of healthcare's most pressing unmet needs. In the U.S., noroviruses are responsible for an estimated 21 million infections annually, including 109,000 hospitalizations, 465,000 emergency department visits and an estimated 900 deaths. The annual burden of norovirus to the U.S. is estimated at $10.6 billion. Noroviruses are responsible for up to 1.1 million hospitalizations and 218,000 deaths annually in children in the developing world.

There is currently no approved treatment or vaccine for norovirus, and the ability to curtail outbreaks is limited. Few companies, if any, are developing antiviral treatments for this disease. Because of the significant unmet medical need and the possibility of chronic norovirus infection in immunocompromised individuals, new antiviral therapeutic approaches may warrant an accelerated path to market.

By targeting viral replication, we believe it is possible to develop an effective treatment for all genogroups of norovirus. We are developing inhibitors of the RNA-dependent RNA polymerase and protease of norovirus. These enzymes are essential to viral replication and are highly conserved between noroviral genogroups. Therefore, an inhibitor of this enzyme might be an effective therapeutic treatment or short-term prophylactic agent when administered in a closed environment.

To learn more about norovirus, please visit the information page at the Centers for Disease Control and Prevention (CDC).

CDI-988 – Norovirus and Coronavirus Protease Inhibitor

CDI‑988 is the first oral antiviral drug candidate being developed for the prevention and treatment of norovirus infections. CDI-988 was specifically designed and developed using our proprietary structure-based drug discovery platform technology as a broad-spectrum pan-viral inhibitor , targeting a highly conserved region in the active site of noroviruses, coronaviruses and other 3CL viral proteases.

A Phase 1 randomized, double-blind, placebo-controlled, single-center trial in healthy adults conducted in Australia showed that oral CDI‑988 was safe and well tolerated at all tested doses up to 1200 mg. No serious treatment‑emergent adverse events (TEAEs), no clinically relevant ECG changes and no clinically significant lab or pathology abnormalities were reported.

CDI-988 is being evaluated in a norovirus challenge Phase 1b randomized, double-blind, placebo-controlled study at Emory University School of Medicine. The study’s primary endpoint is efficacy in reducing the incidence of clinical symptoms; secondary endpoints include reduction of viral shedding and disease severity, and safety and pharmacokinetic profiles.

The FDA has granted Fast Track designation to CDI-988 for treatment and prophylaxis of norovirus infection. FDA Fast Track designation is intended to facilitate the development and expedite the review of drugs that treat serious conditions and address unmet medical needs. The designation enables early and frequent communication with the FDA throughout the development process, allows for rolling review of a New Drug Application (NDA), and may qualify a product for Priority Review at the time of NDA submission.

Noro Polymerase Inhibitor

We continue to identify and develop non-nucleoside polymerase inhibitors using our proprietary structure-based drug design technology platform.