Idenix Pharmaceuticals (IDIX)

[DewDiligence]

Re: Tyzeka vs Baraclude slow starts

This excerpt from a post by dewophile is probably the best explanation to date (from msg #374 with emphasis added):

>>
…the Baraclude experience seems to indicate uptake is slow and then picks up steam over time. I always assumed it had to do with the chronic nature of hep B therapy - specifically pts already on therapy will stay on that drug irrespective of availability of a newer more potent agent out there until there is viral breakthrough (which happens rather often but not that often). So newly diagnosed pts may start a new agent, especially now that one is available that is competitively priced and palatable to third party reimbursers, but the largest pool of existing hep B pts on therapy will stay on older treatment until mandated by their condition… and often when they start the new agent the older therapy may be continued in combination, which is why older drugs like lamivudine have really not declined much. Over time newer agents will garner the lion’s share of the market, but it may just take more time (and the recent momentum of Baraclude sales is consistent with this as well).
<<

In fact, Baraclude picked up nicely after a very slow start ($20M during the first year) and is now selling at a $200M annual run rate.

One thing we can say for sure is that the slow start for Tyzeka is not due to a deficiency in the drug itself. If it were, we would know about it from the FDA label.