https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8225296/
"In a study demonstrating the in vitro antiviral activity of ivermectin, upon incubation of infected Vero/hSLAM cells with 5 μM ivermectin, there was an approximately 5000-fold reduction of viral RNA by 48 hours in ivermectin treated samples as compared with control. The IC50 of ivermectin was found to be approximately 2.5 μM. Ivermectin seems to act on IMPα/β1 and inhibits the nuclear translocation of SARS-CoV-2 (Caly L et al., 2020). Further in-silico studies are required to confirm this target of ivermectin in SARS-CoV-2. The concentrations of 2.5 and 5 μM correspond to plasma concentrations of 2190 and 4370 ng/mL, respectively. These concentrations are 50–100 times the peak plasma concentration achieved with the 200 μg/kg of ivermectin (the US Food and Drug Administration recommended dose for treatment of onchocerciasis) (Chaccour C et al., 2017). Even with a dose 10 times greater than this dose (i.e., 2000 μg/kg), a peak plasma concentration of only ~250 ng/mL has been achieved (Guzzo CA et al., 2017)."
"On the basis of the rationale above, any significant antiviral activity could not have been achieved with the dose used in the study and the resultant plasma concentration of the administered ivermectin. Thus, although ivermectin, in vitro, is a potent inhibitor of SARS-CoV-2 replication, in vivo, the plasma concentration required to achieve the antiviral effect far exceeds the therapeutically applicable dose."
This thread discusses why the example of Uttar Pradesh's program isn't good evidence.