Biotech Values

[biomaven0]

>MDVN

I personally think enzalutamide is going to take the PCa market eventually. Right now, the label is only for post-chemo, but (assuming insurance doesn't balk) I think there will be a fair bit of use instead of docetaxel. Obviously the results of the pre-chemo trial and the trial vs. Casodex will have a big impact on eventual usage, but I'm pretty confident that both these trials will be favorable. Just like in CML, I'm a believer in using the big guns first rather than keeping them in reserve. Using the weaker agents is just an invitation to developing resistance - that's exactly what happens leading to what used to be called "hormone refractory" PCa.

As against Zytiga, the big advantage (particularly for earlier stages) is no prednisone. I also think the capabilities of enzalutamide against splice variants is significant and so the drug is actually more potent than is Zytiga. Note for some unclear reason there was a dramatic difference between median time to PSA progression and median time to death in each of the two drug trials - 0.7 months for Zytiga and more than 10 months for enza.

I can't say I've built a model for peak sales - it's not easy to do. The earlier it is used the longer time on drug will be, but it's certainly not that hard to envision peak sales in PCa of $3 billion. (After all there are about 30k deaths from PCa in the US each year, so even if use is restricted to pretty late-stage patients there is easily a target population of 50k).

The potential breast usage is still obviously pretty speculative. I drew Sally's attention to this aspect and she discusses the possibility in her blog:

http://pharmastrategyblog.com/2012/02/the-role-of-the-androgen-receptor-in-breast-cancer.html/

Peter