PAA Chart, page-28

Hi 10x - a good observation.

The bigger dose at the commencement of treatment is called a loading dose and is typically used in drugs that are metabolised more slowly before being elimnated form the body. In the case of monepantel, we know from animal studies that it metabolises very quickly to monepantel sulfone - mean residence time (MRT) of 4.9hrs - but monepantel sulfone is subsequently metabolised much more slowly (MRT=111hrs).
https://pubmed.ncbi.nlm.nih.gov/19614841/
It therefore makes sense to give a loading dose to achieve a drug concentration that is in the target range more quickly, and then switch to a lower maintenance dose to keep it there.

Regarding safety, the drug exhibits low toxicity and has a very good safety profile. If you're interested, you can read more about this in the work done when Zolvix was initially registered, which includes toxicology and safety studies:
https://apvma.gov.au/sites/default/files/publication/14141-prs-monepantel.pdf

It's also worth a mention here that the company has previously reported that MPL has shown a biphasic effect, meaning more is not better.

Cheers

Densy