The safety issues have been all over the place - hard to know if they are class effects or (perhaps more likely) because most of the molecules were built off the same scaffold if I recall correctly.
This probably doesn't advance the discussion much, but, per its 10-K filed today, ARRY disclosed:
"Compared to other p38 inhibitors, ARRY-797 has distinct properties: it is highly selective, has exceptional potency in whole blood samples, has a differentiated pharmacokinetic profile and is highly water soluble."