By Zachary Stieber
A large study examining ivermectin against COVID-19 included more participants than was reported in 2023, researchers acknowledged in a new correction.
A U.S. government-funded trial arm examining ivermectin was said to have included 1,206 participants, including 602 who received ivermectin. The actual number of participants was 1,432, with 708 receiving ivermectin, Dr. Suanna Naggie, the study’s lead author, said in a May 16 letter to the editor announcing the correction.
“The blinded statistical team made an error in the implementation of exclusion/inclusion criteria such that 106 participants in the ivermectin group and 120 participants in the placebo group who should have been included in the analysis cohort were not,” Dr. Naggie said.
She said the mistake stemmed from excluding participants who were listed as missing “study completion status.”
“During the review process, staff in the unblinded statistical team did not identify the erroneous exclusion and thus the issue was not elevated for review,” according to Dr. Naggie, who said she was writing on behalf of her co-authors.
Dr. Naggie did not respond to requests for comment.
The original publication, for instance, reported that the median time to sustained recovery among ivermectin recipients was 11 days, the same number of data as people in the placebo group. In the updated publication, the median time in the ivermectin arm was still listed as 11 days, while the recovery time for placebo recipients is 12 days.
The hazard ratio of time to recovery remained 1.02, which is a non-statistically significant benefit for ivermectin recipients.
The posterior probability for benefit from taking ivermectin was .65, lower than the original .68. Both were beneath the prespecified benchmark of .95.
The conclusions for time to recovery, the primary outcome, remain unchanged. Researchers wrote: “The data do not provide evidence of a conclusive treatment benefit when using a bayesian noninformative prior, no prior, with various approaches to imputing missing symptom data, or when restricting the analysis to participants who received the drug within 2 or 3 days of symptom onset and across severity of symptoms reported on day 1. The probability that ivermectin reduced symptom duration by 24 hours was less than 0.1%.”
Researchers found that ivermectin recipients felt unwell with COVID-19 one hour less than placebo recipients, down from 3 hours and 20 minutes in the original paper.
Two additional hospitalizations were recorded for ivermectin recipients, and no additional hospitalizations were recorded for the placebo group. Only a handful of adverse events were recorded in the missing participants, including a serious adverse event in each arm.
“The inclusion of these participants does not affect the study interpretations or conclusions,” Dr. Naggie said.
Critics of the research say there were a number of issues, including how some participants did not receive ivermectin for days after testing positive for COVID-19, undermining the attempt to study ivermectin as an early treatment.
“To discover that over a year later, the study investigators ’suddenly’ discover that 226 participants were erroneously excluded simply raises even more concerns as to how carefully the trial was conducted,” Dr. Pierre Kory, one of the critics, told The Epoch Times via email.
In addition to ACTIV-6, some other trials and studies havefound little to no benefit for ivermectin against COVID-19. On the other hand, some trials and studies havefoundsigns the drug, which is approved in the United States to combat conditions caused by parasitic worms, works in COVID-19 patients.
