Timeline: Recruitment for the IMerge trial and interim analysis

[Fishermangents]

(from sdrawkcabeman, YMB 7 March 2016)

The initial cohort of up to 30 pts won't require all sites to be recruiting. I think a safe estimate is 0-3 pts per site; obviously sites w/higher population density might recruit more pts, and several very populous regions are among the recruiting locations. I est 20-30 sites to enroll the initial cohort in an acceptable time frame. CT site lists 20 recruiting, JNJ's site lists 19, so if they're going for all 30 pts, or more, a few more sites might come online. And remember, the active sites aren't updated in real time.

Here's what we can loosely measure based on # of sites recruiting. Pts are screened for up to a month, and we know time to TI is ~11wks, so a little less than 4 months till they can say anything about a pt's response in the interim analysis. If the analysis includes duration (which it doesn't necessarily have to for the interim), then another ~8wks to say something about duration, for a total of about 6 months from first dose for analysis.

So if more sites become active, then we know they're not meeting enrollment #s with the current list, which may push back the interim analysis by 4-6 months from any updated list, and the last recruitment update was in Feb. If only a few more sites become active, or no additional sites become active, then we know the interim analysis will be sooner.

I doubt it will take any longer than Mar to fill 30 pts for one of JNJ's global trials, and considering enrollment began in Dec2015, they likely have somewhere nearing 30 pts right now, if not already fully enrolled. So I think it's a matter of enrollment numbers putting us at interim analysis anywhere in July-Sept, or if enrollment is slower or robust duration data is sought, then Oct-ish.

The difference between the pilot study and IMerge is that there isn't a selection for splicesome mutations in IMerge. In retrospect, I think that handicapped the MDS-RARS data in the pilot. I think we'll see a greater spectrum of responses this time, re: secondary outcomes.