In collaboration with Dr Scott Plevy, a clinical gastroenterologist at the University of Pittsburgh Medical Center, SP304 was shown to be effective in preliminary experiments conducted in an inducible animal model of colitis, the TNBS murine model. Additional preclinical experiments are underway to further define the drug’s therapeutic potential.
The drug is designed for treatment of inflammatory bowel disease (IBD) and other gastrointestinal (GI) disorders. SP304 is an orally deliverable, highly stable peptide, which acts locally in the GI tract and is not absorbed into the body.
The compound is an analog of native human peptide uroguanylin, a guanylate cyclase receptor agonist (GCRA) normally produced in the intestinal tract, but which is dramatically under-expressed under pathological conditions.
Dr Kunwar Shailubhai, senior vice president of Synergy Pharmaceuticals, a subsidiary of Callisto, said: “SP304 is biologically more potent than uroguanylin and, unlike uroguanylin, it exists in a single biologically active conformation, making it easier to synthesize and manufacture.” He added: “These features distinguish SP304 from any other currently known GCRA and make the compound suitable for drug development.”
The company is now looking to move their preclinical programs forward towards the clinic. Following the completion of outstanding animal studies, Callisto anticipates applying for FDA approval to gain investigational drug status to further development.