NanoViricides Files Rare Pediatric Disease and Orphan Drug Applications for NV-387 Against Measles and MPox

NanoViricides, Inc. has filed applications for both Rare Pediatric Disease Drug Designation and Orphan Drug Designation for its antiviral candidate NV-387 as a treatment for measles, and separately filed for Orphan Drug Designation for NV-387 as a treatment for MPox. The company announced the measles Rare Pediatric Disease Drug Designation application on April 7, 2026, which is expected to be joined with an Orphan Drug Designation application filed in February 2026. For MPox, the company filed an Orphan Drug Designation application on February 12, 2026.

If approved, orphan drug designation would qualify NanoViricides for incentives including tax credits for qualified clinical trials, exemption from certain user fees, and potential seven years of market exclusivity after approval. A Rare Pediatric Disease Drug Designation for measles would make the company eligible for a Priority Review Voucher upon approval of the drug, which is a tradable instrument that has recently fetched around $160 million upon sale.

Measles cases have been rising in the USA, with 1,661 laboratory confirmed cases already reported across 33 states as of April 2, 2026, according to the CDC. A total of 2,286 confirmed cases in 48 outbreaks were reported in 2025. The rate of hospitalization in 2026 has decreased to about 5% from the 11% rate in 2025. About 70% of the cases have been in pediatric subjects (0-18 years of age), which qualifies NV-387 for Measles Treatment as a Rare Pediatric Disease Drug. At least 8% of cases in 2026 to date, and at least 7% of cases in 2025 occurred in vaccinated individuals.

For MPox, the incidence rate in the USA was approximately 2,042 cases in 2025, well below 200,000 cases, qualifying NV-387 for Orphan Drug Designation. The World Health Organization declared a "Public Health Emergency of International Concern" for MPox in 2022 due to the spread of MPXV Clade II into Western countries, ending it about a year later. A new PHEIC was declared by WHO again in August 2024 due to the spread of MPox Clade Ia/Ib in the African region, ending it in September 2025.

There is no approved drug for the treatment of measles, although an effective vaccine exists. Similarly, there is no approved drug for the treatment of MPox. Tecovirimat (TPOXX) and brincidofovir (TEMBEXA) were approved by the US FDA for Smallpox, both under the "Animal Rule." Tecovirimat has failed to show any clinical effectiveness in a clinical trial for treatment of MPXV infections, and brincidofovir treatment resulted in drug-induced liver disease in three out of three treated MPox patients.

NV-387 is the only drug candidate to the company's knowledge that has demonstrated strong in vivo activity against lethal infection with the Measles virus in a humanized animal model study. For MPox, NV-387 has shown strong effectiveness in a mouse model of dermal lethal infection of ectromelia, an orthopoxvirus closely related to viruses that cause smallpox and mpox. NV-387 has successfully completed a Phase I human clinical trial demonstrating safety and tolerability in healthy adults with no reported adverse events.

The Rare Pediatric Disease Priority Review Voucher program was re-authorized by the US Congress and signed into Law by President Trump on February 3, 2026, as part of the Consolidated Appropriations Act of 2026. NanoViricides employed the expert services of Only Orphans Cote, LLC, a regulatory consultant firm founded by Dr. Timothy Cote, who previously served as the Director of US FDA Office of Orphan Products Development, for developing these applications.