Suvorexant does have some clear strengths, such as no attenuation of efficacy even after one year of continuous dosing. However, MRK’s unwillingness to run a head-to-head study tells me that, in all likelihood, Suvorexant will turn out to be a just a reasonably good sleep drug rather than the Holy Grail insomniacs have been waiting for.
You need to remember that these are not the decision makers that had these viewpoints, except for Darryl Schoepp. MRK makes these decisions in the so-called Project Development Committee, and these types of decisions are made by a few (my bet is before the committee wide discussion). These folks on the CC stated that it would be difficult to run the study with CR Ambien or with Lunesta. Some truth there?
I would bet that this type of study is in the planning stage. Would you run the study with CR Ambine or with Lunesta? I would choose the former. I do not know the limitations of using CR Ambien, is it approved for long term use in the EU? I have no skin in the game thus no motivation to look that up. As I mentioned a while ago and raised by you and another on this thread, tachyphylaxis is a big issue with GABA-A agonists, especially the subtype 1 receptor agonists. So maybe for now they do not think such a study is so important due to this issue. I could think of many aspects of the study that should show superiority in favor of suvorexant.
Perhaps pricing is viewed to be a big issue for a dramatically large market share?