It's an old (for the internet standard) article, but I don't recall having seen this in the news before, and it actually was on Slashdot a few days ago.
…and yes, it's as nasty as it looks.
Goldman asks: 'Is curing patients a sustainable business model?'
"GILD is a case in point, where the success of its hepatitis C franchise has gradually exhausted the available pool of treatable patients," the analyst wrote. "In the case of infectious diseases such as hepatitis C, curing existing patients also decreases the number of carriers able to transmit the virus to new patients, thus the incident pool also declines … Where an incident pool remains stable (eg, in cancer) the potential for a cure poses less risk to the sustainability of a franchise."
Goldman Sachs warns sales from the most successful disease treatments are difficult to maintain.www.cnbc.com