JNJ's prostate cancer drug test was halted early because the results were clear: "An independent data monitoring panel stopped the study early based on findings which showed that the Zytiga therapy significantly delayed the growth of prostate cancer and helped patients live longer compared to placebo."
This speaks to our earlier discussions that A-7 results are not a clear-cut home run.
Wrong, I hold 15,000 shares.
I am holding because I have as much invested in VICL as I am comfortable with.
I have serious faith that the trials will work.
I just don't plan on buying anymore, thus my hold rating.
It's a case of no news is good news. They have so much invested in A-7 that they cannot afford to less than stellar results. I suspect the data is going to have numerous confounding factors and it will be subgroup data analysis which will show strong success for A-7 just as we have seen in the phase II trial. Unfortunately subgroup analysis is not considered as strong data in the biostats world. Don't get me wrong, I think A-7 and DNA/plasmid technology is wonderful. At the end of the day it is a gene therapy.
In effect, you're saying Vical knows the a-7 trial is not going well so they are delaying said trial to prevent the stock price from falling ?
That is quite the stretch on your part.
"crying about why there can't be an early halt"
Nobody is crying for a halt or expecting one. The question speaks to the delay for lack of events, and whether that can be interpreted as meaning A-7 is working really well. Somebody raised the legitimate question of whether the test would be stopped early if that were the case, and conversely, since the test is not being stopped, can we draw the conclusion that it is not a blowout success? The opinions that it would not be halted were well drawn, except when the tone was that it's impossible. That makes no sense to me. This is merely an academic discussion and an attempt to gain some insight, not impatience with the stock. If it were, it would have happened four years ago after two years of waiting for a flu vaccine.
Survival curves can be generated without the prescribed number of deaths being met. Overall survival is somewhat more difficult to predict and the difference between the DTIC and A-7 groups will need to be greater for statistical significance. However the pre-trial thesis is completely blown at this point because the DTIC arm was supposed to have met the prescribed end point at this time. VJ gives the 3 probable outcomes of the trial death rate A-7 >/</= to DTIC. At this point it is exceptionally unlikely that the DTIC has done spectacularly different than its historical controls and those survivors from the DTIC arm do not follow traditional pathway. It serves no purpose to extend the trial to December unless something else is going on. At this point nothing is preventing either DTIC or the A-7 remaining survivors from trying on either Yervoy or Zelboraf. Infact if you are a long term survivor after receiving DTIC or A-7 and still have a residual tumor burden that as an oncologist you would be obligated to at least offer Yervoy or Zelboraf to any pt enrolled in the Vical study. I suspect this will continue to complicate the results and waiting will only confuse the results. I strongly suspect Vical wants to wait until the HSV phase I/II study is enrolled prior to releasing the data so that the stock price does not crash as hard. Somewhat conspiracy theory driven but I honestly do not think at this point waiting for the prescribed event number is rational.
While I haven't read everything, I am not aware of the safety panel getting access to anything other than adverse events. I understand that it monitored the trial for adverse events and that the trial was going so well, the panel decided further montoring was not necessary. If no one has access to all the individual response and event information, no one would have been in a position to call the trial early. If I am wrong on this point, please let me know. Thanks!
There is an article on this subject at seeking alpha--saying that the study was designed with a power sufficient to see results at the end of the trial (if assumptions are true about efficacy), but the study is not over-powered. That means that there are not enough subjects in the trial to show statistical significance early, if the assumptions of efficacy suggested by the stage 2 results hold up. Thus the study cannot end early, even if it were not blind, because it would not likely be able to show statistical significance early (if the drug acts like it did in stage 2)--and statistical significance is what is needed for any approval.
<<< I am not aware of the safety panel getting access to anything other than adverse events. >>>
I agree, and your view is consistent with VJ's answer to an analyst that asked about this issue. If it's going to take several weeks to determine how many patients responded, it seems like a stretch that doctors at each site, with just a few patients, would be able to conclude anything. It is also true that it would be very difficult for a doctor to conclude anything regarding the secondary endpoint, survival.
Given the specifics of this clinical trial and the way A-7 is expected to work in patients, halting it early seems extremely unlikely. To me, this is no big deal. Very few trials are halted early, while many more drugs successfully meet their clinical trial endpoints and receive FDA approval. What is a big deal is that events are not happening at nearly the rate initially expected. Could chemo be working much better than expected in this trial? I doubt it very much.