One recent drug industry setback I haven't noted around here - well, OK, to be more specific, it's a Merck setback, and boy must they be getting sick of those - is the FDA's "not approvable" letter for the Singulair/Claritin combination pill.
As the folks at the InVivoBlog note, it sure was hard, from one perspective, to see that one coming. After all, Claritin (loratadine) has an exemplary safety record and has been on the market for many years now, and Singulair (montelukast) has been selling in the billions of dollars as a stand-alone drug. No doubt many people have taken, and are taking, the two as separate pills. So you combine them and get a "not approvable": right.
The In Vivo people speculated that this might be a safety problem, since the agency has been mighty jumpy about that area recently, but Merck has now told them that safety and tolerability weren't raised in the FDA letter.
Well, what does that leave? Manufacturing? Hardly possible, given the way that these two drug substances are already being cranked out. That, as far as I can see, leaves good old efficacy. You could always argue that putting the two compounds into one pill improves patient compliance, etc., if the combination itself is useful in the first place. But in this case, I'd guess that the problem is that the combo has turned out to offer no benefit over either drug taken alone. Hard to make a case under those circumstance, it is.
And if you look into the history of a Singulair/Claritin idea, that appears to be just the problem. As the Wall Street Journal's Health Blog notes, the companies had already found no benefit for seasonal allergies, compared to either drug standing alone. Supposedly they were able to come up with some sort of nasal congestion data (what a joy that must be) that showed an edge this time, but yikes - how desperate do you have to be to take things to that point, after you've already seen no benefit in the main endpoints?
So why are Merck (and Schering-Plough) spending money on this kind of last-gasp line extension? Surely there are better places to burn cash. I've never been sympathetic to the argument that money spend on promotion is somehow stolen from R&D, but this sort of thing is another matter. Stupid R&D most definitely steals money from smarter R&D, and here's some of it that's made off with the swag.