Pfizer: Covid pill with HIV drug cuts the risk of hospitalization, death by 89%

How does this drug compare in efficacy to piperine, assuming they use the same mechanism? [1] not the HIV drug Is there a write-up on nih.gov? I am making an assumption that if the mechanism is the same that piperine would be the baseline for comparison.

Piperine slows the breakdown of many molecules by the liver. It is most commonly used with supplements that the liver breaks down too fast thus improving their bio-availability.

[1] - https://en.wikipedia.org/wiki/Piperine

Spoiler alert: the mechanism of action of pfizermectin is the same as ivermectin, even though they're different drugs. How did Pfizer think of using this non-obvious mechanism of action?