That's the opposite of a real scientific advantage. Most drug effectiveness is related to the population in which it is deployed, based on their combination of

That's the opposite of a real scientific advantage. Most drug effectiveness is related to the population in which it is deployed, based on their combination of unique risk factors and etiologies. Socioeconomic factors (and I mean that in its accurate usage, not just a short-hand for "income") are a huge example: they're one of the biggest predictors of health outcomes and responsiveness to various treatments, and using a population with wildly different SES factors fundamentally kills the trial. A sample population which accurately reflects the general population in which a drug is to be deployed is assessed, in clinical trials, as something known as "external validity" (as opposed to "internal validity", which is just whether the experiment is properly designed to test its stated hypothesis). tl;dr apparent drug effects in Africans are not useful indicators of drug effects in Americans, particularly if your premise is "those drugs have different outcomes in Americans."