The US FDA has recently approved an interesting drug:
en.wikipedia.org/wiki/Flibanserin
Flibanserin is intended to increase sexual interest and arousal in females who experience FSIAD:
Adding it to Big Pharma would be both a fun little reference to ongoing events (kind of like the marijuana legalization event… I loled at that) as well as an opportunity for fun little gameplay mechanic. “Treats FSIAD” could be the top-level cure in the Sexual Health tree, and supplying it can increase the demand for the other cures in the tree, in the inverse of the way Hypertension effects the Blood tree. After all, less FSIAD -> more sex -> higher demand for warts meds/contraceptives/erectile dysfunction meds. You could even throw in an increased infection rate of HIV to boot. 
I think that would be the only case in Big Pharma (Or the only one I’m aware of) where a cure would increase demand for other cures. A player who heavily invested in Sexual Health cures can use this as a strategy to drive up the profit margin (and drive down the saturation) of the other drugs. I suppose that the same logic might apply to Alleviates Erectile Dysfunction, but that drug is purely to cause or improve erections (assuming it acts like Viagra) whereas FSIAD is a lack of sexual desire as well as arousal, so curing it would clearly increase the amount of sex going on. 