RE:RE:RE:RE:RE:RE:RE:RE:RE:Financial AdvisorTo put a statistical spin on thing.
The FDA approves things not based on the %CR but based on the statistics for that data presented.
If you think about a company with a drug that has a 40% respsonse in the first 10 patients treated. That 40% response translates into a true response that could be anywhere from 10-70%. Imagine you have a massive jar of jelly beans and you pull 10 out randomly. Just because your small handful contains 4 green ones and 6 red ones doesn't mean that the massive jar is made up of 40% green ones. The FDA requires a big enough handful so that EVEN WHEN YOU CONSIDER the lower bound, the results are good. In the jelly bean example, 10% is the lower bound.
The FDA panel from way back indicated support for a drug that could achieve
- 40%-50% at 6 months (note that they don't list 3m CR or CR at any time)
- 30% for 18-24 months, with the lower bound of the 95% confidence interval excluding 20%
Using the most up to date patient numbers, my math says for 95% confidence interval we are at:
3m: 44-71% based on 57 treated and evaluable.
6m: 40-65% - (just meet this one on the lower bound) based on 53 treated and evaluable.
12m: 27-51% based on 42 treated and evaluable.
15m: 23-49% (meets the 20% on the lower bound) based on 39 treated and evaluable.
So Graham, while nothing is proven, one can say that true efficacy of Ruvidar for initial (3month) CR is somewhere between 44 and 71% and the true 15 m CR is between 23 and 49%.
Adstiladrin was approved on 24% CR with a study of 103 patients that had reached the 12m mark. The true value of of CR therefore may not have even reached 20% lower bound based on the number of patients. The 95% confidence interval is 14-34% for that CR.