EXEL: the "official" answer to my question
I missed the 10/31 conf call, which Seeking Alpha published today.
Here, FWIW, is the response to a question by David Miller that is similar to the question I posed concerning the real motives for EXEL deciding to allocate resources to the 306 study (without SPA). I must say that after considering this response, I think the company's strategy makes more sense to me. I am still a lot more dubious about EXEL as an investment than I was last week.
Here is the relevant snip from the transcript on Seeking Alpha:
David Miller – Biotech Stocks Research
Okay. I’m a little confused as to why you need both trials. If you just run the ‘307 trial you would pick up functionally out in the real world. You would pick up the patients that you are enrolling in the ‘306 trial, because doctors would go ahead and use based upon the label from '307 go ahead and use cabo in these patients anyway. So I am confused as to why you’re running both trials. I mean, I understand why you need '307 to get approval for '306 but I don’t understand why the reverse is true.
Gisela M. Schwab
I think just to clarify, we don't believe we need '307 in order to support '306. We view that as two separate trials that are both in their own right capable of supporting registration. Now what these individual trials are assessing is; number one, '306 assesses symptom relief, pain alleviation as the primary endpoint. And that is an endpoint that is hard to assess in a very large globally run study.
As has been demonstrated by the fact that none of the recently approved drugs have a pain label, although they collected pain information. And the reason is that if you have a large study rolling out that enrolling globally, it is difficult to standardize the instrument and ensure that the translations and language of the instrument that is supporting pain connection is acceptable in all these languages.
And the other issue is that oftentimes in large studies that are enrolling quickly, pain information is collected with less rigor. And so you end up with a lot of missing data. So that's in part why we believe other compounds that have collected some pain information have not received a pain label. So that’s why we want to run a dedicated pain study. In addition, we want to run a dedicated overall survival study that will be a simple study that can roll quickly and that we can rollout globally. So with both really we are supporting a very compelling potential label that addresses both the quantity as well as the quality of life in prostate cancer patients.
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