Entdoc, with the references to p-value, null hypothesis and statistical significance, I have been brushing up on the old college statistics base. I recall now why I didn't really enjoy calculating statistics then, or now, LOL! I have come to the conclusion that very standout results are going to be needed for Bavi to show statistically significant results using null hypothesis methodology, especially when the number of patients in a trial arm is 40.
To make the complex more simple, note that there were about forty patients subscribed into each of the five control arms from the two NSCLC trials PPHM has reported. That has about 200 patients total in Bavi studies and 120 actually receiving Bavi.
In the NSCLC trial results reported in February, there were two arms:
1. Docetaxel plus Carboplatin as a control arm
2. Bavituximab (3 mg/kg) and D plus C, for comparison.
In the NSCLC trial results reported today, there were three arms:
3. Docetaxel plus Placebo
4. Docetaxel plus Bavituximab dosed at 1 mg/kg dosage
5. Docetaxel plus Bavituximab dosed at 3 mg/kg.
One patient exhibiting a response in a group of 40 is a 2.5% shift. Consider today's news release results summary and how much the profile on a waterfall diagram would need to shift to and how many patients in the study pool would need to be impacting the statistic. My observation is that the median progression free survival and median overall survival show the most potential for presenting statistically significant results. We can't calculate significance of PPHM Bavi statistics with data provided. Yet, we can draw some insights.
Obviously, the longer it takes for the MOS results to finish tallying, the stronger the data. The MOS needs to have 20 of 40 patients surviving 50% longer for Bavi to exhibit 9 months MOS vs. a control are 6 months. A 3 month survival extension, most would agree, is a big deal. PPHM is announcing to investors today that such MOS results are being posted or exceeded.
Best wishes and IMO.
KT
TUSTIN, CA -- (Marketwire) -- 05/21/12 -- Peregrine Pharmaceuticals, Inc. (NASDAQ: PPHM) today announced positive top-line results from its randomized, double-blind, placebo-controlled Phase IIb trial evaluating two dose levels of bavituximab plus docetaxel versus docetaxel plus placebo (control arm) in patients with second-line non-small cell lung cancer (NSCLC). Data from the trial showed a doubling of overall response rates (ORR), the primary endpoint, and an improvement in progression-free survival (PFS), a secondary endpoint, in patients treated in the bavituximab-containing arms when compared to the control arm. Another secondary endpoint, median overall survival (OS), in the control arm has already been determined at less than 6 months, while the median has not been reached in either bavituximab-containing arm.
Based on independent radiology reviews and current status of patients, top-line data from the trial are as follows:
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Bavituximab Bavituximab
Placebo (1 mg/kg) (3 mg/kg)
Treatment Arm plus plus plus
docetaxel docetaxel docetaxel
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Overall Response Rate (ORR) 7.9% 15.0% 17.9%
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Median Progression-Free
Survival (PFS) 3.0 months 4.2 months 4.5 months
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AI
