Though measles outbreaks remain somewhat under control, they aren't going down. Deaths have held steady at around 150,000 per year since 2007.

The developing world can get something of a pass for not being able to contain measles. In anti-science hotbeds like the coasts in America and some countries in Europe, it's unforgivable. What was once only the domain of religious fundamentalists is now dominated by wealthy elites who count on the herd immunity of commoners to protect their children and refuse to vaccinate. But that clearly does not work.

A new antiviral drug, ERDRP-051, may protect people infected with the measles from getting sick and prevent them from spreading the virus to others, an international team of researchers says, but the big question will be whether or not the people most likely to get measles have parents that will allow them to take a drug.

The researchers tested it in animals infected with a virus closely related to one that causes the measles. Virus levels were significantly reduced when infected animals received the drug by mouth. It also prevented the animals from dying of the disease.

The authors say ERDRP-051 can be produced cost-effectively, stockpiled and administered by mouth, and could boost eradication efforts by rapidly suppressing the spread of the virus during local outbreaks.

Dr. Richard Plemper of Georgia State University and colleagues at the Emory Institute for Drug Discovery (EIDD) say ERDRP-0519 blocks replication of the pathogen.

In collaboration with Dr. Veronika von Messling from the Paul-Ehrlich-Institute, the researchers tested the drug by turning to a virus very closely related to measles virus, the canine distemper virus, which causes a highly lethal infection in ferrets. All of the animals treated with ERDRP-0519 survived infection with the distemper virus, remained disease free and developed robust immunity against the virus.

Plemper said the drug could be used to treat friends, family and other social contacts of a person infected with measles virus, who have not developed symptoms yet but are at risk of having caught the disease. "The emergence of strong antiviral immunity in treated animals is particularly encouraging, since it suggests that the drug may not only save an infected individual from disease but contribute to closing measles immunity gaps in a population."

Dr. Richard Plemper. Credit: Georgia State

The researchers emphasize the drug is not intended as a substitute for vaccination, but as an additional weapon in a concerted effort to eliminate the measles.

As experienced with many antiviral drugs, the virus can become resistant against this inhibitor. The investigators have examined the issue of viral escape and found that resistant viruses were in most cases less virulent. Equally important, the researchers observed that transmission of the resistant viruses between animals was impaired compared to the parent strain. These results are promising because they indicate resistance is unlikely to rapidly become widespread in the virus population.

While the drug is very encouraging thus far, additional research is needed before it could be considered for use in humans.

"We are delighted to see our long-standing collaboration with Dr. Plemper and his team at the GSU IBMS come to fruition, and we look forward to continuing to leverage the medicinal chemistry and drug development capabilities at the EIDD in this and future collaborations with his group," said Dr. Michael Natchus, director of operations at the EIDD.

Citation: Stefanie A. Krumm, Dan Yan, Elise S. Hovingh, Taylor J. Evers, Theresa Enkirch, G. Prabhakar Reddy, Aiming Sun, Manohar T. Saindane, Richard F. Arrendale, George Painter, Dennis C. Liotta, Michael G. Natchus, Veronika von Messling, and Richard K. Plemper, 'An Orally Available, Small-Molecule Polymerase Inhibitor Shows Efficacy Against a Lethal Morbillivirus Infection in a Large Animal Model', Sci Transl Med 16 April 2014:  Vol. 6 no. 232 DOI:10.1126/scitranslmed.3008517. Source: Georgia State University