Drug development and snakebite
Newshub has a commendably restrained story about some biochemical research into possible starting points for Covid treatment
Brazilian researchers have found that a molecule in the venom of a type of snake inhibited coronavirus reproduction in monkey cells, a possible first step toward a drug to combat the virus causing COVID-19.
Not everyone is so calm about it: The Hill says Brazilian viper venom shows promise as drug to combat COVID-19, the Daily Express says Covid breakthrough as deadly Brazilian snake venom 75% effective in stopping virus, and Indian site Zee News says Jararacussu pit viper, found in Brazil, can be the answer to Coronavirus, says study.
The research paper is here.
Researchers in Brazil were already studying the properties of a fragment of a protein from the venom of the jararacussu, a South American pit viper. This fragment blocks a protease, a protein-snipping enzyme, that is needed by the SARS-Cov-2 virus. The protein fragment isn’t a drug on its own — and the protein it comes from definitely isn’t; it’s in the snake venom for a reason, and that reason isn’t to benefit animals that get bitten. However, this genuinely is one of the ways we get new drugs. A protein fragment from the venom of a related South America pit viper, which blocked a human protease enzyme, was the starting point for developing ACE inhibitors, an important class of medications for high blood pressure and heart failure.
A few more things to point out, though. First, the research paper is studying the ability of the SARS-Cov-2 virus to infect lab-grown hamster kidney cells in a Petri dish. These aren’t particularly realistic targets; they’re just convenient. The paper describes the use of a ‘positive control’, a chemical that they know is effective at stopping infection of these hamster cells under lab conditions. You might have heard of this chemical; it’s called chloroquine. And finally, the tweet from The Hill that pushed me to write this post has a picture of a pretty green snake. It’s not the jararacussu. It’s an African snake that’s not especially closely related and whose venom hasn’t been studied all that much. They have the picture handy because a snake of that species bit a handler at the San Diego zoo in April. Zee News also use a pretty green snake picture, and it’s even less closely related.
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »