OL-135

OL-135 is hands down one of the cleaner ways researchers learned to turn up the body's own anandamide instead of flooding CB1 with a THC-style agonist; you inhibit FAAH, the enzyme that chews up anandamide, and endocannabinoid tone rises right where it is already being made. The appealing part is the reversible design; it is an alpha-ketooxazole that sits in the active site as a covalent-but-reversible hemiketal, so it is essentially competitive rather than a permanent carbamate like URB597.

In the animal work it pretty much did what an endocannabinoid enhancer should do; raised brain anandamide and knocked down neuropathic and inflammatory pain, itch, and visceral pain, and every one of those effects was blocked by CB1 or CB2 antagonists, which tells you the mechanism is real. It is worth being straight that OL-135 itself stayed a lab tool; it never went to the clinic, and its reversible potency was shorter-lived than the later oxazole analogs the same group built for oral, long-acting dosing. As a scaffold though it is a landmark; a lot of what is known about drugging FAAH gently traces back to this molecule.

OL-135 is an investigational research chemical with no human clinical data; its safety profile is defined only by preclinical rodent studies. In those studies it produced cannabinoid-receptor-mediated analgesic, anti-allodynic and anti-pruritic effects without overt sedation at effective doses, and its effects were blocked by CB1/CB2 antagonists. Because it broadly elevates endocannabinoids, CB1-mediated central effects are possible at higher exposure. As a reversible inhibitor it is shorter-acting than irreversible carbamate FAAH inhibitors. It is not approved, scheduled, or manufactured to human-use standards, and the FAAH-inhibitor class generally has drawn caution after unrelated clinical FAAH-inhibitor programs failed on efficacy or safety grounds. Not for human consumption.