Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Smallpox pill promising

20.03.2002


New drug could soon thwart smallpox outbreaks


A smallpox pill could help stem an outbreak quickly.
© WHO



An anti-smallpox pill could be on the way if a new compound that shows promise in animal tests proves safe and effective in humans. Such a pill could provide the best method for controlling an unforeseen smallpox outbreak, its developers claim.

The need for new ways to treat smallpox has only become an issue in recent years as the threat of a deliberate release of the virus intensifies. Smallpox - a highly contagious and often lethal viral disease - was officially eradicated by vaccination in 1979.


The new chemical is a modified version of the drug cidofovir, which is used to treat infections in AIDS patients. In 1999 John Huggins of the US Army Medical Research Institute in Fort Detrick, Maryland, and his colleagues found that cidofovir stops mice dying from cowpox1, a relative of smallpox. But cidofovir is expensive and must be injected.

Now Huggins, along with Karl Hostetler of the Veterans Affairs San Diego Healthcare System in California and others, has turned cidofovir into a drug that can be swallowed - by animals at least. "This drug could become the first line of defence," says Hostetler.

The team presented their findings today at the International Conference on Antiviral Research in Prague, Czech Republic.

Fat chance

"We disguised cidofovir so the body thinks it’s a dietary fat," Hostetler explains. His team attached to cidofivir’s active component a molecule called lecithin, a breakdown product of fat found in all foods. This Trojan horse approach tricks the body into absorbing the drug and carrying it to where it is needed.

Small doses of the new compound - called HDP-CDV - killed the virus in smallpox-infected cells. "The big surprise was that its antiviral activity went up 100-fold compared to cidofovir," says Hostetler.

A single, daily dose of the drug also cured mice of cowpox, Huggins found. Untreated mice died within days.

What’s more, cowpox was undetectable in the respiratory tracts of mice treated with HDP-CDV. Because smallpox is spread by infectious droplets that are coughed up, this finding suggests that HDP-CDV might help to stem an epidemic.

These early tests raise hope that HDP-CDV might be incorporated into an anti-smallpox pill that could be distributed widely without the need for public-health workers to administer it, says Hostetler.

"But there is tons of work left to do," he warns. Even though the new compound is based on an existing drug, it must undergo the same rigorous testing as any other. The team don’t expect that process to begin for at least another year.

Outbreak outcry

The possibility of an effective drug for smallpox is likely to fuel the debate among smallpox experts about the best way to control a future outbreak. Many prominent scientists argue that antiviral drugs such as cidofivir shouldn’t play a prominent role.

Antivirals may save lives and perhaps reduce transmission, but they do not confer immunity to the disease, as vaccines do, the argument goes.

Donald Henderson, head of George W. Bush’s newly created Office of Public Health Preparedness, is a prominent sceptic. The use of cidofovir "would be limited to administration at or shortly after infection had occurred to prevent the virus from multiplying and eventually causing disease", he says.

Antiviral drugs would best be used to treat people who can’t be vaccinated, says Henderson. Those with weak immune systems can suffer adverse, even fatal, reactions to smallpox vaccine.

Joseph Esposito, a poxvirus specialist at the US Centers for Disease Control and Prevention in Atlanta, Georgia, agrees: "A new drug would be very important." But in terms of a national strategy, "the first line of defence is a proven one, and that’s vaccination," he says.

But while questions loom about the number of smallpox vaccine doses available to limit an outbreak, and about the possibility of a smallpox virus being engineered that can outwit existing vaccines, antivirals deserve a fair trail, says Hostetler.

References

  1. Bray, M. et al. Cidofovir protects mice against lethal aerosol or intranasal cowpox virus challenge. Journal of Infectious Diseases, 181, 10 - 19, (2000).

TOM CLARKE | © Nature News Service

More articles from Health and Medicine:

nachricht Hot cars can hit deadly temperatures in as little as one hour
24.05.2018 | Arizona State University

nachricht 3D images of cancer cells in the body: Medical physicists from Halle present new method
16.05.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

12th COMPAMED Spring Convention: Innovative manufacturing processes of modern implants

28.05.2018 | Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

 
Latest News

Cognitive Power Electronics 4.0 is gaining momentum

28.05.2018 | Trade Fair News

Organic light-emitting diodes become brighter and more durable

28.05.2018 | Physics and Astronomy

12th COMPAMED Spring Convention: Innovative manufacturing processes of modern implants

28.05.2018 | Event News

VideoLinks
Science & Research
Overview of more VideoLinks >>>