FDA Approves Tembexa to Fight Weaponized Smallpox Virus Amid Fears of COVID Lab Origins

Smallpox is a disease that was eradicated in 1980 from occurring naturally in humans. However, the World Health Organization (WHO) has long feared that the variola virus, which causes smallpox, could be used as a bioweapon if it got into the wrong hands.

Though the disease has been eliminated, the variola virus is still being kept in two labs—one in Atlanta and the other in Russia.

The U.S. Food and Drug Administration (FDA) on Friday approved the drug Tembexa to treat smallpox, which is a contagious disease that's sometimes fatal.

Concerns of the variola virus have become even more heightened with fears of the COVID-19 coronavirus originated from a science lab.

"Although naturally occurring smallpox no longer exists, concerns about potential uses of variola virus as a bioweapon has made smallpox drug development an important component of the U.S. medical countermeasures response," the FDA stated on Friday.

Prior to its eradication 41 years ago, smallpox was spread by close human contact, similar to the flu and COVID-19. Smallpox symptoms typically didn't show until 10-14 days after being infected. They include fever, headache, backache and exhaustion.

Infected persons oftentimes would develop a rash that had small, pink bumps before they progressed into pus-filled sores that eventually crusted over and turned into scars.

Further complications from smallpox can include brain damage (encephalitis); open sores on the clear, open part of the eye; blindness; and death.

Smallpox Treatment
The U.S. Food and Drug Administration (FDA) on June 4, 2021, approved the drug Tembexa to treat smallpox, which is a contagious disease that’s sometimes fatal. Photo by PATRICK T. FALLON/AFP via Getty Images

Tembexa received the FDA designations of priority review, fast track and orphan drug. That allowed a faster application review of within six months, as opposed to the typical 10 months or greater. It was allowed to move along faster in testing because of the disease's seriousness, and it was designated an orphan drug because of the disease's rarity.

Tembexa was studied in animals that have viruses that are very closely related to the variola virus. One group received Tembexa and the other received a placebo. The group receiving Tembexa had a higher survival rate than those that didn't, which determined the drug's effectiveness rate.

The FDA applied the "animal rule" for testing since it wasn't "feasible or ethical" to conduct human clinical trials.

"FDA approved Tembexa under the agency's Animal Rule, which allows findings from adequate and well-controlled animal efficacy studies to serve as the basis of an approval when it is not feasible or ethical to conduct efficacy trials in humans," the FDA stated.

The most common side effects of Tembexa are stomach cramps, nausea, vomiting and diarrhea.

Tembexa comes in 100mg tablets.

The drug was developed with additional oversight from Biomedical Advanced Research and Development Authority (BARDA) of the U.S. Department of Health and Human Services.

Chimerix Inc. was granted approval of Tembexa by the FDA.

Newsweek reached out to the FDA and the WHO for comment.

The Centers for Disease Control and Prevention (CDC) stated that smallpox may have been around for at least 3,000 years, and it spread around the world through the growth of civilizations.

The CDC said that three out of every 10 people who contracted smallpox died from the disease.

English doctor Edward Jenner developed a vaccine in the late 1700s. The disease didn't spread as quickly, and by the 1950s, WHO aggressively tried to eradicate the disease, which was one of the most deadly scourges in history.

On May 8, 1980, the World Health Assembly declared the disease gone. After that, WHO deemed that stocks of the variola virus needed to be kept for future study if needed. Those stocks were eventually narrowed down to only two labs in the world. One is in Atlanta, and the other is in Koltsovo, Russia, according to the CDC.