food for thought

As a discussion point, I'd like to put forward a theory about the progress of the Cvac 2b trial and why the interim data announcement has been delayed.
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Two closely spaced US conference presentations suggest that PRR are ramping up their publicity program. Certainly the very sluggish take up of ADR's underlines the importance, firstly of this campaign, and secondly the release of interim 2b data, to stimulate interest among US investors.

But to be frank, unless the SP drops to compellingly low levels, (and it hasn't yet), if I was a US based investor, I might now be waiting for the validation of interim 2b efficacy data, before I committed my funds. And according to Dr Neil Frazer, we shouldn't expect this interim 'Progression Free Survival' data before the end of this year at the earliest. (macenroc's post #7826242}

However, I believe that PRR may already be in possession of some positive interim PFS data, covering the trial group getting Cvac. But they lack the control group data needed for comparison and validation at this stage.

What’s my reasoning?

I suspect that the delay in announcing interim data is due to the difficulty PRR experienced in achieving full enrolment in the 15 person control group. These patients receive current standard of care (but not Cvac).

Two key points:
1. Unlike phase 3, the 2b trial protocols are not 'blinded'. Patients know from the start which group (Cvac or control) they have have been allocated to. I understand there was a trend for patients assigned to the control group to abandon the 2b trial in favor of other treatments. This is supported by a number of posts during last year by 2b trial participants in online patient forums, including some who said that PRR eventually had to change the trial conditions.

Specifically they suggested that in the end, PRR offered free Cvac treatment to any control group candidates who relapsed during the trial period. Soon after this change, PRR announced full enrolment, in September 2011. So I think it's possible that a significant proportion of the 15 control group patients may have joined the trial quite late in the enrolment period, possibly as recently as just 8 months ago.

By comparison, the patients receiving Cvac have been progressively enrolling since early July 2010, ie. up to 22 months ago. So I suspect there could be an appreciable difference in the average period covered by the data of the two groups. And there just hasn’t been enough time for the control group data to be in any way meaningful.

2. According to twinpeaks (post #7548695), MR told an Ord Minnet briefing on Dec 14th 2011 that "at this stage all the patients are in good health ............ "

Now that was a year and a half after patient enrolment started. That is often not a significant time in clinical trial terms, but given what I understand to be the debilitating progression/relapse rate of ovarian cancer; to have all 45 Cvac trial candidates "in good health", according to the CEO, up to a year and a half after the trial started is significant in my view.

In fact, imo it was a surprisingly clear hint to investors from the CEO that Cvac treatment was working at that point.

I just can't believe it took me so long to realize it.
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So my point is this. With MR's guidance in December, and given that nearly two years has now passed since initial enrolment, I think it's possible that PRR may already have in hand interim PFS data for the Cvac group. But they lack meaningful data over a significant timeframe, from the late enrolling control group, and that is what's delaying an interim announcement.

Worth waiting for imo.

Good luck all. Herro