Receptos, Inc., a San Diego-based biotechnology company, announced promising new clinical data for its drug candidate RPC1063 for ulcerative colitis. The drug was first discovered and synthesized at The Scripps Research Institute (TSRI) by the research groups of Professor Hugh Rosen and Professor Ed Roberts.

Ulcerative colitis (UC) is a key form of inflammatory bowel disease (IBD), characterized by chronic inflammation in the colon and rectum. This pathological condition together with Crohn’s disease affects more than one million people nationally, according to the U.S. Centers for Disease Control and Prevention. Moreover, the disease causes major morbidity globally, and its incidence and prevalence seems to be increasing with time. The pathogenesis of UC seems to be due to an uncontrolled immune response to an unknown environmental stimulus in the large bowel. Although there is treatment for some patients with ulcerative colitis, according to the Crohn’s and Colitis Foundation of America, the disease progresses in 23 to 45% of patients in spite of medication, and in the end surgical removal of all or part of the colon is required.

This clinical trial, sponsored by Receptos, Inc., is called TOUCHSTONE, and is a multi-national, including North America, Europe, and Asia Pacific, a multi-center, double-blind, randomized, placebo-controlled Phase 2 trial to study the effect of two doses of RPC1063 administered orally versus placebo for the treatment of moderately to severely active ulcerative colitis over 8 weeks, followed by a blinded maintenance period of 24 weeks for patients to achieve clinical response during the induction period. This study shows that the drug candidate RPC1063 will likely improve the standard treatment for the enrolled 199 patients with active, moderate to severe disease ulcerative colitis. The results demonstrated that when administering the treatment in a 1 mg dose of RPC1063 for eight weeks, 16.4% of patients entered clinical remission, when compared to 6.2 % of patients on placebo. The RPC1063 was generally well tolerated by the treated group.

“We are delighted that RPC1063 is showing promise for ulcerative colitis patients in addition to its already significant efficacy and safety data in multiple sclerosis,” said Prof. Hugh Rosen in the Receptos press release. “Research carried out at TSRI since 2002 has led to the discovery of fundamental mechanisms that can be modulated for potential treatments of a variety of autoimmune diseases including ulcerative colitis and multiple sclerosis, and the unique multidisciplinary environment in chemistry and biology at TSRI allowed this progression to clinical trials,” added Prof. Hugh Rosen.

The drug candidate RPC1063 was a “hit” after the screening of various compounds from the molecular library of National Institutes of Health at Scripps Florida’s Molecular Screening Center, using a technology from the Rosen lab in La Jolla. The Roberts and Rosen labs performed medicinal chemistry to transform this compound into a drug candidate. Afterward, TSRI licensed the compound to Receptos, which is developing RPC1063 to submit for approval by the U.S. Food and Drug Administration.

Finally, due to these promising results, Receptos intends to start a Phase 3 trial and Phase 2 studies of RPC1063, respectively, for ulcerative colitis and Crohn’s disease.

Notably, Receptos is currently assessing the effect of RPC1063 in a Phase 3 study as a therapy for multiple sclerosis, since this drug seems to exert is action through the modulation of sphingosine 1-phosphate receptor therefore its plausible to think that it may be applied for the therapy of other autoimmune diseases, such as multiple sclerosis.