A research team lead by scientists of the University of California at San Diego has developed a molecule that could potentially weaken or even stop influenza A H3N2. The invention comes after more than 65.000 Americans fell victim to the flu, resulting in hundreds of deaths. 

A research team lead by scientists of the University of California at San Diego have developed a molecule that could potentially weaken or even stop influenza A H3N2. The invention comes after more than 65.000 Americans fell victim to the flu, resulting in hundreds of deaths.

This year’s influenza A H3N2 is especially aggressive. Unlike other viruses, instead of replicating through the hosts DNA, it uses its own enzyme to replicate, called RNA-dependent RNA polymerase. The enzyme consists of subunits, one of which is used for replication. Scientists had to find a vulnerable area in its structure: “One of the major targets has been a particular RNA polymerase subunit that the virus uses,” said Seth Cohen, Ph.D., a professor at UCSD. “It is a nucleic-acid processing protein that is required for the life cycle of the virus, for it to replicate and to propagate, and it is dependent on manganese metal ions.” 

The virus relies on two manganese ions to initiate its replication of genetic information. The drug will bind both ions at the same time, thus stopping the protein’s ability to work, leaving it unable to spread and reproduce. After successfully testing it on the RNA polymerase enzyme, Cohen is hopeful this invention can stop the whole virus in its tracks: “This is a medical intervention that will slow down the virus if not completely stop it”, said Cohen. “The drug could potentially eliminate the virus on its own or just sufficiently slow its reproduction so that the body can ultimately clear it. It’s like taking and antibiotic for a viral infection” (). 

Japanese pharmaceutical company Shionogi is pursuing a similar approach. Their drug Xofluza (baloxavir marboxil) killed the flu virus in 24 hours. The company plans to file for FDA approval this year.