Many years ago, I met in the saloon bar of an inn I occasionally frequented, an elderly gentleman who was totally convinced that the Earth was flat or, as he patiently and helpfully explained, not totally flat, as there were mountains and canyons dotted about. Whatever arguments were advanced by the other users of the pub were as water off a duck’s back to this stubborn chap. Copernicus was clearly wrong, and he firmly believed that an injudicious step too near to the Earth’s edge could result in catastrophe. This was my first real meeting with someone who was impervious to rational argument in clinging to his belief.

In recent years the propensity for people to propagate irrationality has been dramatically encouraged by the growth of the many social mediums and nowhere has this been more clearly demonstrated by the emergence of pandemic diseases. First, we had AIDS and the claims that the human immunodeficiency virus was a manufactured bioweapon. Ebola virus was subject to similar claims but then we witnessed the largest pandemic of the 21st century with Covid. Instantly the web was full of conspiracy theories and awash with spurious medical claims for treatment and prevention. Despite the often bizarre nature of these claims (inhaling bleach anyone?) they are still being touted on the various outlets and attempting to refute them is often met with claims of government skulduggery and big pharma profiteering.

Those of us involved with drug development and safety monitoring are aware of the burden of proof required to develop and maintain medicinal products. However once again, those who spread wild accusations feel no such need. This has been demonstrated once more with the continuing saga of Ivermectin. Ivermectin is a widely available cheap drug used extensively in veterinary medicine, as well as approved for certain parasitic infections in man. Invermectin was shown dramatically to reduce the proliferation of SARS-CoV-2 virus in cell culture, albeit at concentrations over 100 times those achieved by oral dosing. The resulting social media storm led to many people self medicating with ivermectin, including totally inappropriate animal preparations. The US FDA was so concerned that they issued their own warnings on the internet with the catchy phrase “You are not a horse. You are not a cow. Seriously, y'all. Stop it.” Somehow, I can’t see the UK authorities adopting the same folksy tone! As the noise about Invermectin rose in the Twittersphere, interest rapidly fell in scientific circles. Most randomised trials showed no effect from the drug in Covid. However, like my flat earth friend above, this wasn’t enough for the believers: they criticised the dosages used in the studies, the numbers involved, the type of patients and many other factors, including deliberate suppression for commercial reasons. Now we have the publication of the ACTIV-6 study in the Journal of the American Medical Association. This was a large study involving 1591 patients in 93 sites across the USA. Trial subjects were randomized to either Ivermectin or placebo and the primary outcome measure was time to clinical recovery. The results clearly failed to show any significant treatment effect from ivermectin. However, I’m not altogether sure that this well constructed study will stop those who promote Ivermectin as the answer to Covid.

It’s tempting to think of the time and effort required to change entrenched opinions, not just in medicine but in all walks of life. However, for those of us in the business of developing and monitoring drugs this whole Invermectin episode reminds us of the need for soundly constructed evidence-based answers to some of those who peddle ill considered, ineffective and potentially dangerous remedies.