There's a very real debate among health providers and pharmaceutical companies about if there's a business case for "curing" conditions. A classic product tier would be something like "$50/mo. to treat symptoms, $5,000 one time to cure", but the societal outcry would be enormous if put in those relatively unambiguous terms. As a result you get situations where investments into cures are dwarfed by investments into tweaking an existing drug just enough to get another patent, or what have you.
Or put another way, there's a lot of money in aging and cancer.