Infectious disease. Combating emerging viral threats

Abstract

Most approved antiviral therapeutics selectively inhibit proteins encoded by a single virus, thereby providing a “one drug-one bug” solution. As a result of this narrow spectrum of coverage and the high cost of drug development, therapies are currently approved for fewer than ten viruses out of the hundreds known to cause human disease. This perspective summarizes progress and challenges in the development of broad-spectrum antiviral therapies. These strategies include targeting enzymatic functions shared by multiple viruses and host cell machinery by newly discovered compounds or by repurposing approved drugs. These approaches offer new practical means for developing therapeutics against existing and emerging viral threats.

Antiviral drugs that selectively inhibit unique viral proteins provide a “one drug, one bug” solution, while broad-spectrum drugs can restrict multiple viruses by inhibiting either common viral enzymatic functions or host factors commonly required by several viruses. The lower panels depict specific stages of the viral life cycle (blue rectangles) often targeted by each class of drugs. Specific examples of broad-spectrum compounds are denoted in orange with the corresponding targeted proteins or pathways in grey. CypA (Cyclophilin A).