NanoViricides Advances Broad-Spectrum Antiviral NV-387 to Phase II Trials for MPox and Respiratory Infections
Key Insights
NanoViricides has completed Phase I clinical trials for NV-387, a broad-spectrum antiviral drug, with no reported adverse events or dropouts, demonstrating excellent safety and tolerability in humans.
The company is preparing Phase II clinical trials for NV-387 to treat MPox (search) in Africa and viral respiratory infections, with preliminary approval already obtained from regulatory authorities in the Democratic Republic of Congo.
NV-387 has shown superior efficacy compared to existing antivirals in animal models, outperforming oseltamivir, peramivir, baloxavir for influenza (search), and remdesivir for COVID-19 (search).
NanoViricides, Inc. (NYSE American: NNVC) has achieved significant clinical milestones with its lead drug candidate NV-387, a broad-spectrum antiviral therapy that completed Phase I clinical trials with exceptional safety results and is now advancing to Phase II development for multiple viral infections.
The company reported that NV-387 completed Phase I clinical trials with no patient dropouts and no reported adverse events, demonstrating excellent safety and tolerability in humans. This safety profile positions the drug candidate for broader clinical development across multiple viral indications.
Phase II Development Strategy
NanoViricides is currently completing a Clinical Trial Application (CTA) for a Phase II clinical trial of NV-387 for the treatment of MPox (search) disease in Africa. The company has already obtained preliminary approval for its clinical trial protocol from ACOREP, the regulatory agency in the Democratic Republic of Congo (DRC).
The timing is critical as MPox (search) continues to spread and surge in African countries, remaining endemic in the DRC and neighboring countries. The African CDC has maintained its declaration of Public Health Emergency of Continental Security (PHECS), initiated in August 2024, as of September 2025.
Additionally, the company has proposed a novel adaptive Phase II clinical trial for evaluating NV-387 as a treatment for Viral Acute/Severe Acute Respiratory Infections (V-ARI, V-SARI), with a preliminary clinical protocol already developed for this complex trial.
Superior Preclinical Performance
NV-387 has demonstrated superior efficacy compared to existing antiviral drugs across multiple viral infections in animal models. In a lethal lung infection animal model of influenza (search), oral NV-387 was found to be superior to three known drugs: oseltamivir (Tamiflu®, Roche), peramivir (Rapivab®, BioCryst), and baloxavir (Xofluza®, Shionogi/Roche).
The drug candidate also showed remarkable efficacy against respiratory syncytial virus (RSV (search)), curing lethal lung RSV infection in an animal model. Notably, there is currently no approved drug for treating RSV infection, highlighting a significant unmet medical need.
For COVID-19 (search), NV-387 given both orally and as intravenous injections was found to be substantially superior to remdesivir (Gilead) in a lethal lung infection animal model. The company has developed two COVID-19 drug candidates: NV-CoV-2 (API NV-387) and NV-CoV-2-R, which encapsulates remdesivir within polymeric micelles.
Revolutionary Treatment Approach
NanoViricides believes NV-387 could become a revolutionary antiviral therapy that could be prescribed for practically any respiratory viral infection without first testing for the causative virus, similar to how broad-spectrum antibiotics can be prescribed before testing for causative bacteria. This "empirical therapy" approach would enable immediate treatment and improve effectiveness, as antiviral treatments are most effective when given early.
The company projects that NV-387 would play in a market size of well over $20 billion as a dominant player if approved for such empirical therapy of viral acute respiratory infections and severe acute respiratory infections.
Innovative Nanoviricide Technology
The company's technology is based on mimicking host-side binding sites that viruses use, which remain consistent despite viral mutations. NanoViricides designs chemical mimics of these sites to create virus-binding ligands attached to a base polymer, making the drug appear like a cell membrane to the virus.
The nanoviricide drug is designed to fool the virus into entering the drug micelle and uncoating itself by using the virus's own mechanisms against it. The company believes viruses would not be able to escape nanoviricide drugs because of this design, in contrast to vaccines, antibodies, and most small chemical drugs which viruses readily escape.
Strategic Regulatory Pathway
NanoViricides plans to leverage the MPox (search) studies toward approval of NV-387 as a treatment for smallpox (search) under the US FDA "Animal Rule." The US agency BARDA (search) has programs to support such development if NV-387 qualifies.
A potential acquisition of NV-387 for smallpox (search) under the US Strategic National Stockpile could be worth approximately $1 billion over five years. The company believes NV-387 for treatment of MPox (search), smallpox, and measles would be separately eligible for Orphan Drug Designation by the US FDA, which carries benefits including waived FDA fees, up to seven years of market exclusivity, and research and development tax benefits.
Current Market Landscape
There is currently no approved drug for treatment of MPox (search). Tecovirimat failed in clinical trials for MPox treatment, while brincidofovir entered clinical trials for MPox in January 2025 with interim results anticipated in Q1 2025, though the current status is not publicly known. Brincidofovir carries a black box warning due to increased mortality rates in another indication and has significant safety limitations.
NanoViricides estimates NV-387 has a wide opportunity as a treatment for MPox (search), with a market size approaching $1 billion in the African region alone.
Financial Position and Future Milestones
As of June 30, 2025, the company reported cash and cash equivalent assets of approximately $1.67 million and net property and equipment assets of approximately $6.83 million. The company's cGMP-capable manufacturing and R&D facility in Shelton, Connecticut, enables in-house production of clinical trial drug substance and products.
Key upcoming milestones include completion and submission of the Phase I Clinical Study Report to the Indian regulatory agency, filing of Phase II Clinical Trial Applications for MPox (search) treatment and viral respiratory infections, and filing of Orphan Drug Designation applications to the US FDA.