Protagonist Therapeutics has secured a patent covering orally stable peptide inhibitors of the interleukin-23 receptor (IL-23R), including its lead candidate drug PTG-200. The patent protects PTG-200’s formulation as well the use of this class of inhibitors to treat inflammatory bowel disease (IBD).
The patent provides intellectual property coverage until 2035, David Liu, Protagonist’s chief scientific officer and head of research and development, said in a press release.
Protagonist, based in Milpitas, California, focuses mainly on developing small molecule drugs which specifically block biological pathways that are currently targeted by marketed injectable antibody drugs. PTG-200 was designed based on this approach to change existing treatment strategies for moderate-to-severe Crohn’s disease. It is currently in Investigational New Drug (IND) enabling studies.
“Inhibition of the IL-23 pathway is an effective therapeutic treatment for IBD, as evidenced by a marketed injectable antibody drug for treatment of Crohn’s disease,” said Liu. “PTG-200 is an oral IL-23R antagonist and is designed to offer potential advantages such as improved convenience, patient compliance, safety, tolerability and access to the targeted IL-23 receptors that are highly expressed in the gut associated lymphoid tissue.|
Results from preclinical studies presented at the recent Digestive Disease Week conference in Chicago demonstrated that PTG-200 significantly improved disease outcome of animal models of IBD, through specific inhibition of the IL-23 pathway.
Animals treated with PTG-200 had reduced signs of colon inflammation which are commonly observed in IBD patients. The investigational drug also effectively reduced the levels of well-known inflammatory biomarkers that are activated via IL-23R. These results support the therapeutic potential of PTG-200 to tret IBD. The company plans to initiate a Phase 1 clinical trial later this year.
Protagonist is also developing a new drug, PTG-100, to treat moderate-to-severe ulcerative colitis. The company is now enrolling participants for a Phase 2b clinical trial (NCT02895100) to study its effectiveness, safety and tolerability.