You might have a positive effect on leaky gut, but if that "allowed" you to eat lots of grain with no problem, you'd still run into issues with blood sugar control.
I eat very little grain but not because I have celiac (I don't), and I haven't noticed any health issues I could attribute to a a gluten sensitivity. The reason I have to stay away is because I simply have no "off switch" when it comes to refined grains. I could eat an entire box of cereal or an entire sleeve of crackers (and still be "hungry.") I don't think affecting zonulin would help me there! ;-)
That being said, if you're someone who can control themselves with that stuff, it might be interesting to give the pill a whirl, but I'm with Fasano on this - tinkering with a natural process in the body is always iffy. (Fosamax and Boniva causing MORE bone fractures, anyone?!)
If you know wheat is bad for you, why take a pill that lets you "get away with it?" That's like telling a diabetic to go ahead and keep eating danishes; just up your insulin dose to compensate. :-/
Edited to add: I might have been a little too harsh. If you look at this from the angle that the only reason wheat is bad is because of its effects on the tight junctions lining the gut (and all the nasty things that stem from that), then I'd say pop the pill and go enjoy some fresh baked biscuits. But it seems like there are other issues besides that. Like what I said above with me having nearly no self-control when it comes to refined grain products. I'm not sure where that comes from. To me, it's not the opiate receptor thing making me addicted, because the minute it hits my tongue, the switch gets flipped (long before it's had time to make it to my intestines.) And it's not the sugar either, b/c even grain-based foods that are not sweet at all have that effect on me: plain saltines, plain cornflakes, etc. (Granted, they're all carbohydrate, but not sweet, per se.)