SiteOne Therapeutics Inc. is developing synthetic sodium channel blockers for pain that have a different chemical scaffold and better characterized binding site than competing molecules. The result, according to the company, should be advantages in potency, selectivity and solubility.

SiteOne's sodium channel platform is based on marine guanidinium toxins, which include tetrodotoxins, saxitoxins and gonyautoxins. These small molecules are used as pharmacological tools and have potent activity against voltage-gated sodium channels. The problem is that the difference between a therapeutic and a toxic dose of guanidinium toxins is small.