Is Sovaldi worth its $84,000 price tage?

One of the biggest healthcare issues that is being discussed especially in the United States is cost and in particular, whether newly developed drugs are worth their relatively high cost.  In other words, does the new drug bring a significant improvement in our ability to treat diseases  that is justified by its cost to the patient and/or to society.  One of the most recent drugs that enters into this realm of discussion is Sovaldi that has been developed to treat hepatitis.  http://nyti.ms/1ojC07D