With the astonishingly slow sales ramp to date, it will clearly take longer than three years for Tyzeka/Sebivo to reach $500M in annual sales. I thought NVS and IDIX would do a much, much better job marketing the drug than they have to date.
However, the premise of the argument for a lofty sales figure—rapid growth in the HBV market and an eventual 33% market share for Tyzeka/Sebivo—is still intact, IMO.
NVS has never issued sales projections for Tyzeka/Sebivo. (NVS rarely issues sales projections for any drug.) However, I think it’s reasonable to assume that NVS expected at least $500M in peak annual sales when they licensed the drug from IDIX in 2003.
NVS has paid $110M in Tyzeka/Sebivo milestones to IDIX and has spent at least that much on clinical development and pre-launch marketing. That’s why I find the sluggish early sales of the drug mystifying.