Well, the implication of women earning 77c for every Dollar a man earns is that bosses are biased against women.
Of course, if you look closer into it and check for other factors, such as job preference, hours worked, etc. - or directly compare men and women in very comparable positions, with a very comparable history - the wage gap closes for the most part, leaving only a few percent for biases against women and other factors that can't be checked for.
That's why I'm curious when I see a statistic like this.
At first glance it seems to indeed imply that doctors would prescribe these drugs differently because of bias, but the idea that a large majority of doctors has these racist biases seems to be unlikely to me. Especially because in the article it sounds like it's really just an assumption that the person didn't try to verify in any way. I have to admit that I can't think of many factors that would influence the numbers of prescriptions in such a drastic way though though. But still, I would prefer if actual research was done to find out what's happening before people draw their conclusions based on unfounded assumptions.