So why haven't those other countries done so?
The sad reality is that capitalism provides the required incentive to motivate smart, talented people who can actually innovate. There are of course exceptions, many people are doing this work because it is their passion, and would likely continue doing it even if they weren't paid well, but such people are rare; most people simply want to do a job and receive the maximum compensation they can get -- based upon free market dynamics and relative rarity of someone with their experience, ability, and knowledge.
Nothing in life is free, asshole.
"I dont have to practice safe sex, because there is pill for it" As this article shows the pill doesnt always work.
I wonder how the results would change if they had considered countries like Brazil, which offers a cocktail of ~17 drugs for free for everyone HIV positive since 1996 (when patents were fought in the supreme court IIRC). Many americans and europeans (also japanese) come here every year to get some of these medicines for a fraction of what they would cost back home.