My brother was an MD, and we had many science chats. He was also a PhD physicist as well as an MD, and I am a biochemical engineer. We chatted many times about the difficulty the straight laced, tunnel visioned AMA products (US doctors), have with understanding complex systems, synergistic effects, masking effects of multi dimensional control feed back systems. They tend to think in linear single variable terms.
The Human is far more complex than one variable at a time.
So my point is that a one component system is different that a 2 component system. Beyond that, I can only speculate as I am not familiar with those drugs, or ingredients, etc. I was just suggesting the danger in writing the 2 drug system off based on a one drug test.
Ambition with out knowledge is like ship in dry dock. Going nowhere fast!