It's not uncommon for people to use clen during PCT, for reasons I'm not too sure of (you're body will develop a tolerance to the stuff hella quick).
As someone mentioned above, albuterol is a prescription replacement to clenbuterol. It's milder. Truthfully, any sort of beta-2 agonist could hold some benefit, to whatever degree. The resultant increase in cAMP will certainly aid in some nice anticatabolic effects, perhaps some anabolic, and should definitely help with your endurance levels.
There's some research on this stuff to show it has been anabolic; however, it has nothing to do with coming off an anabolic steroids cycle and a lot more to do with people with muscular dystrophy. That being said, if "I'm going on PCT" is actually a secret code for "I am in the closet about my muscular dystrophy but wish to remedy it as well as grow my muscles", this might be more than worth your while.