The first patients with ulcerative colitis (UC) and Crohn’s disease (CD) have been dosed in two Phase 2 trials assessing the effects of SHR0302, Reistone Biopharma‘s investigational drug for the treatment of patients with inflammatory bowel disease (IBD).
SHR0302 is a potent selective inhibitor of Janus kinase 1 (JAK1), one of the proteins from the JAKs family that controls inflammation in response to cytokines, which are molecules released by immune cells that play a major role in inflammation and autoimmunity.
JAK inhibitors are able to dampen the body’s inflammatory and autoimmune response by interfering with the signaling cascade controlled by JAKs.
Unlike other types of JAK inhibitors currently available, SHR0302 only inhibits the activity of JAK1, leaving other JAK proteins unscathed. For this reason, selective JAK inhibitors such as SHR0302 may be a safer option for patients, as their use minimizes the occurrence of undesirable side effects arising from all-around inhibition of JAK proteins.
The safety and efficacy of SHR0302 in patients with moderate to severe UC and CD is currently being assessed in two multi-center, randomized, double-blind, placebo-controlled, Phase 2 trials: RSJ10101 (NCT03675477) and RSJ10201 (NCT03677648).
“We are excited to advance our selective JAK1 inhibitor into our global Phase 2 trials for UC and CD. Reistone is committed to bringing this innovative drug developed in China to the world,” Min Irwin, CEO and co-founder of Reistone, said in a press release.
RSJ10101 is a 16-week trial, in which UC patients who complete the initial eight-week phase of treatment will have the chance to continue treatment for another eight weeks during the blinded extension phase of the study.
In the first phase, UC patients will be randomly assigned to receive one of three doses of SHR0302, or a placebo. Patients who receive a placebo during the first eight weeks of the trial will be randomly assigned to one of the three groups receiving SHR0302 during the extension phase. The trial is expected to enroll 152 participants.
The primary objective of the study is to assess the percentage of patients achieving a clinical response at week eight. Secondary endpoints will include assessing the percentage of patients achieving clinical remission and endoscopic remission (mucosal healing) at week eight.
RSJ10201 is a 24-week trial, in which CD patients who complete the initial 12-week phase of treatment will have the chance to continue treatment for another 12 weeks during the blinded extension phase of the study.
Similar to RSJ10101, CD patients in RSJ10201 will be randomly assigned during the first phase to receive one of three doses of SHR0302, or a placebo. Those who are treated with a placebo during the first 12 weeks of the trial will be randomly assigned to one of the three groups receiving SHR0302 during the extension phase. The trial is expected to enroll 144 participants.
The primary goal of the study is to assess the percentage of patients achieving clinical remission at week 12. Secondary endpoints will include assessing the percentage of patients achieving clinical remission and displaying a clinical response at week 1, 4, 8, 12, 13, 16, and 24.
“There are still high levels of unmet medical need for UC and CD treatment. Despite anti-TNF agents being entrenched in the treatment of UC and CD, there remains a significant number of patients who lose response to these biological drugs. High cost of using these biologics is another issue,” Aik Han Goh, chief medical officer of the company, commented. “Small molecule drugs, such as SHR0302, potentially provide a new alternative treatment resolution for the patients.”
Reistone currently holds the global rights to use SHR0302 for multiple autoimmune disease indications after having obtained a license from Jiangsu Hengrui Medicine, the product’s original manufacturer.