MIST II trial cancelled

The MIST I and II trials have been the centre of a lot of controversy.  You might not remember the name, but you may remember the treatment.  Some people have a patent foramen ovale (PFO), which is an opening in the heart.  A simple operation is able to close this opening, and some people have found a reduction in migraine attacks after the procedure.

The idea was to conduct multiple trials and collect data in MIST I, II, III and IV.  MIST II was more ambitious than MIST I, a larger study with a longer follow-up time.

But a number of problems came out after MIST I.  First, the results were less than encouraging.  Then in October a co-investigator of the trial, Dr Peter Wilmshurst, expressed concerns about how the data was managed and reported.  Those running the trial then claimed Dr Wilmshurst was in fact not a co-investigator, but was dropped due to protocol violations.  Then other experts called for an independent review, but it was claimed patients would need to give their consent, and so on and so on….

In the end, the NMT Medical (who was running the trial) closed it.  It looks like the bottom line was money – the trial required a lot of patient screening, and it was going to drag on too long to be "worth it".

This was an important study, and it’s too bad it died.  There was a lot of media attention, making it sound like this was a cure-all for migraine, which is unlikely.  It would be nice to get the confusion cleared up.

The good news is that this is not the end of PFO treatment for migraine.  Other trials are on and continuing and we will hear more about it in the future.  Meanwhile, NMT continues its studies but will be focusing on PFO closure and stroke.  Read more in NMT Medical to shut down patent foramen ovale/migraine MIST II trial.