The findings, published in Nature Microbiology, come from scientists at the Center for Translational Antiviral Research (CTAR). Their work focused on canine distemper virus, which produces a disease in ferrets that closely resembles measles.

Antiviral Blocks Two Routes of Transmission

The researchers tested a recently developed drug candidate called GHP-88310 (described in Science Advances). The medication is a broad-spectrum inhibitor of the viral polymerase, an enzyme the virus needs in order to reproduce.

The team examined whether prophylactic (shortly before or after exposure) use of the drug could prevent transmission through direct contact or shared air. GHP-88310 successfully blocked both forms of spread. When the drug was used to treat animals that were already infected, it also reduced the length of time they remained capable of transmitting the virus.

“Silencing measles outbreaks quickly is essential to reestablish control over the virus,” said senior author Richard Plemper, a Regents’ Professor and director of the CTAR. “This study follows our recent development of the drug candidate GHP-88310. It demonstrates that the drug is suitable to augment traditional ring vaccination against measles.”

Measles Outbreaks Return Across North America

Measles has reemerged in the United States since 2025, causing thousands of infections across several states, hundreds of hospitalizations and three confirmed deaths. Canada and Mexico have also experienced major outbreaks involving multiple deaths, raising concerns about whether North America can maintain its measles elimination status.

“We were very excited to see that GHP-88310 given by mouth completely prevented airborne transmission in our ferret model of measles,” said first author Carolin Lieber, a senior postdoctoral fellow in the Plemper lab. “This finding is unprecedented for a viral polymerase inhibitor and demonstrates the extraordinary antiviral potency of this drug.”

Tests Mimicked Homes and Classrooms

To model realistic transmission conditions, the researchers created a controlled system in which infected and uninfected animals either came into direct physical contact or shared the same airspace without touching.

“We designed the study to recapitulate viral spread between people with direct contact, for instance in a household, and between more distant social contacts, for example in classrooms or other indoor settings that bring people into proximity without direct interaction,” said Plemper. “In addition to this prophylactic benefit, GHP-88310 used therapeutically shortened the duration of disease in our model. If equally applicable to human hosts, it may shorten the severe social and economic burden of prolonged quarantine of patients and further aid outbreak management.”

Drug Candidate Moves Toward Clinical Testing

The researchers are now preparing GHP-88310 for formal clinical trials.

Other contributors to the study included Josef Wolf, Claire Ruckel and Lauren Harrison of the Center for Translational Antiviral Research in the Institute for Biomedical Sciences at Georgia State.

The research was supported by the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH).