So they believe (and apparently have demonstrated) that ivermectin acts as a 3CL Protease Inhibitor. There are a few other drugs that can do this, as well as a couple more being trialed. I read a study a while back that determined that while coronaviruses were able to mutate and reproduce around 3CL inhibitors, that the resulting mutations were significantly weaker and reproduction reduced.
Here’s a link with the full study. Lots of info on 3CL PI’s, including ivermectin. WARNING: long, geeky link below.
Researchers have known for some time that 3CL PI’s are a potential treatment against coronaviruses. In fact, Pfizer’s 3CL PI currently in trials is based on a molecule they were developing for SARS-1 back in 2003, but the virus disappeared and the project was shelved. I’m not yet fully convinced on the efficacy of ivermectin vs COVID in the real world, but it looks hopeful.
+1