This week, the Food and Drug Administration updated its guidance manual for Tpoxx, which has been prescribed to millions of patients infected with the virus. The global healthcare regulator has warned against the overuse of the lone drug available to treat monkeypox, stating that a single mutation in the virus can render the pill ineffective.

FDA officials have cautioned that a single molecular change to monkeypox DNA can have a large impact on antiviral therapy. They advised that the drugs should be used judiciously as the viruses are constantly evolving to overcome obstacles to causing infection, including drugs and immune detection in the human body. On Thursday, the Centers for Disease Control and Prevention stated that Tpoxx should not be prescribed to any healthy adult who does not present any severe symptoms.

Tpoxx is an FDA-approved drug used to treat the smallpox virus. However, due to the similar structure of monkeypox and smallpox, the drug has been used for treating monkeypox in an experimental and strictly controlled environment by federal officials. The drug works by targeting a single protein found in the viral structure, thereby preventing its replication.

(Source: https://www.today.com/health/disease/us-warns-monkeypox-mutate-resist-antiviral-drug-rcna48054)