A report of 4 patients is hardly called a “study” and even less a “cure”. Anti-viral drugs may have their application in long-covid cases, but usually the side-effects outweigh the benefits.

Also the author claims in the summary:

This study presents a novel theory of sequestered COVID-19 virus in the body.

That is quite a stretch to get to from these 4 subjective reports. Neither is it novel, nor is there solid evidence in the reports.