The researchers had been working, though informally, to investigate the major studies surrounding ivermectin.
After reviewing 26 major studies based on the use of the drug against the virus, they found that more than a third of the trials either had serious errors or signs of potential fraud, the BBC reports.
Advocates of the medicine on social media even recommend the version of the drug used for animals and claim that evidence is being covered up pointing to a number of scientific studies.
Dr Kyle Sheldrick, one of the researchers, said the group had not found "a single clinical trial" claiming to show ivermectin prevented COVID deaths that did not contain "either obvious signs of fabrication or errors so critical they invalidate the study.”
Some of the major problems associated with the studies include the use of the same patient's data multiple times for supposedly different people and evidence that the selection of patients for test groups was not random.
An influential study from Egypt contained patients who turned out to have died before the trial started, among other issues. The study has now been dismissed by the journal that published it.
The group of independent scientists examined virtually every randomised controlled trial (RCT) on ivermectin and COVID - in theory, the highest quality evidence - including all the key studies regularly cited by the drug's promoters, according to the BBC report.
Evidence in five among the 26 studies indicate that the data may have been faked. For example, there were virtually impossible numbers or rows of identical patients copied and pasted.
In another five, there were major red flags as it had numbers that didn't add up and the percentages were calculated incorrectly, while the local health bodies were not aware that the studies were conducted.
As many as 14 authors of these studies failed to send data back, which the independent scientists have flagged as a possible indicator of fraud, the report adds.
However, some of the research papers on ivermectin and COVID-19 contain some high-quality research. But the major problems were all in the studies making big claims for ivermectin - in fact, the bigger the claim in terms of lives saved or infections prevented, the greater the concerns suggesting it might be faked or invalid, the researchers discovered.
While it's extremely difficult to rule out human error in these trials, Dr Sheldrick, a medical doctor and researcher at the University of New South Wales in Sydney, believes it is highly likely at least some of them may have been knowingly manipulated.
A recent study in Lebanon was found to have blocks of details of 11 patients that had been copied and pasted repeatedly - suggesting many of the trial's apparent patients didn't really exist.
The study's authors told the BBC that the "original set of data was rigged, sabotaged or mistakenly entered in the final file" and that they have submitted a retraction to the scientific journal which published it.
Another study from Iran seemed to show that ivermectin prevented COVID patients from dying.
But the scientists who investigated it found issues. The records of how much iron was in patients' blood contained numbers in a sequence that was unlikely to come up naturally.
And the patients given the placebo turned out to have had much lower levels of oxygen in their blood before the trial started than those given ivermectin. So they were already sicker and statistically more likely to die.
But this pattern was repeated across a wide range of different measurements. The people with "bad" measurements ended up in the placebo group, the ones with "good" measurements in the ivermectin group.
The likelihood of this happening randomly across all these different measurements was vanishingly small, Dr Sheldrick said.
Dr Morteza Niaee, who led the Iran study, defended the results and the methodology and disagreed with problems pointed out to him, adding that it was "very normal to see such randomisation" when lots of different factors were considered and not all of them had any bearing on participants' Covid risk.
But the Lebanon and Iran trials were excluded from a paper for Cochrane - the international experts in reviewing scientific evidence - because they were "such poorly reported studies". The review concluded there was no evidence of benefit for ivermectin when it comes to COVID.
The largest and highest quality ivermectin study published so far is the Together trial at the McMaster University in Canada. It found no benefit for the drug when it comes to COVID.
Ivermectin is generally considered a safe drug, though there have been some reports of side effects.
Calls over suspected ivermectin poisonings in the US have increased a lot but from a very small base (435 to 1,143 this year) and most of these cases were not serious. Patients have had vomiting, diarrhoea, hallucinations, confusion, drowsiness and tremors.
But indirect harm can come from giving people a false sense of security, especially if they choose ivermectin instead of seeking hospital treatment for Covid, or getting vaccinated in the first place.
Prof Andrew Hill, from the University of Liverpool, wrote an influential positive review of ivermectin, originally saying the world should "get prepared, get supplies, get ready to approve [the drug]".
Now he says the studies don't stand up to scrutiny - but after he changed his view, based on new evidence emerging, he received vicious abuse.
A small number of qualified doctors have had an exaggerated influence on the ivermectin debate. Noted proponent Dr Pierre Kory's views have not changed despite the major questions over the trials. He criticised "superficial interpretations of emerging trials data".
Around the world, it was originally not opposition to vaccines but a lack of them that led people to ivermectin.
The drug has at various points been approved, recommended or prescribed for Covid in India, South Africa, Peru and much of the rest of Latin America, as well as in Slovakia.
Health authorities in Peru and India have stopped recommending ivermectin in treatment guidelines.
In February, Merck - one of the companies that make the drug - said there was "no scientific basis for a potential therapeutic effect against COVID-19".
In South Africa, the drug has become a battleground - doctors point out the lack of evidence but many patients desperately want access as the vaccine rollout has been patchy and problematic.
One GP in the country described a relative, a registered nurse, who didn't book a coronavirus vaccine she was eligible for and then caught the virus.
"When she started getting worse, instead of getting proper assessment and treatment, she treated herself with ivermectin," she said.
"Instead of consulting a doctor, she continued with the ivermectin and got home oxygen. By the time I heard how low her oxygen saturation levels were (66%), I begged her daughter to take her to casualty.
"At first they were reluctant, but I convinced them to go. She passed away a few hours later."