LAS VEGAS – Ozanimod, an oral agent that selectively modulates the sphingosine 1-phosphate (S1P) 1 and 5 receptor, has a lasting effect on symptoms of ulcerative colitis, according to results from an open-label extension study.
The study extends the phase II TOUCHSTONE trial, in which patients with ulcerative colitis showed significant clinical improvement out to 32 weeks. The current study showed those improvements lasting out to at least 1 year, with about 80% of patients staying on the drug at the end of the study.
With other drug regimens, “the loss rates are at least 50% of the patients, so this is a remarkable level of durability over time,” William Sandborn, MD, chief of gastroenterology at the University of California at San Diego, said at the annual meeting of the American College of Gastroenterology. “With biologics, if you follow patients out for a year or 2, you see a fair amount of loss of response and some of that probably has to do with the formation of antidrug antibodies and immunogenicity,” Dr. Sandborn added.
Dr. William J. Sandborn
In the original TOUCHSTONE study, 197 patients were randomized to placebo, ozanimod 0.5 mg, or ozanimod 1.0 mg, and followed out to week 32. Twenty-one percent of those in the 1.0-mg group achieved clinical remission, compared with 26% in the 0.5-mg group and 6% of those receiving placebo. Clinical response rates were 51%, 35%, and 20%, respectively.
In the open-label study, patients from all arms who did not respond to treatment after the induction phase, or relapsed during the maintenance phase, or completed the maintenance phase (170 patients in total) entered the open-label study with a dose of 1.0 mg ozanimod. At the time of the cut-off, patients in the extension study had been taking ozanimod for at least 1 year.
At the start of the extension study, the partial Mayo Score (pMS) for patients on placebo, ozanimod 0.5 mg, and 1.0 mg were 4.6, 4.5, and 3.3, respectively. All groups showed improvement in pMS by week 44 (1.7, 1.7, and 1.9, respectively)
At week 44, 90.9% of patients had little or no active disease (physician global assessment 0 or 1), 98.4% had little or no blood in their stools, and 84.7% had no blood in their stools.
Adverse events with a frequency higher than 2% included ulcerative colitis flare (5.9%), anemia (3.5%), upper respiratory tract infection (4.1%), nasal pharyngitis (3.5%), back pain (2.9%), arthralgia (2.4%), and headache (2.4%). The researchers noted some transient elevation of alanine aminotransferase or aspartate aminotransferase, but these elevations were temporary and reversed during ongoing treatment; 2.4% of patients experienced ALT and AST levels higher than three times the upper limit of normal, and all were asymptomatic.
Serious adverse events that occurred in two or more patients included anemia (1.2%) and ulcerative colitis flare (2.4%).
“This is a promising oral product with a similar mechanism of action to other lymphocyte trafficking agents,” said Stephen Hanauer, MD, medical director of the digestive health center at the Northwestern University, Chicago, who attended the session.
Ozanimod and other lymphocyte trafficking agents may offer a slightly different profile than some of the other drug classes, such as the anti–tumor necrosis factor agents, according to Dr. Hanauer, because the agents don’t affect lymphocytes already in the tissues. On the other hand, once the drug has acted, its effect may linger. “The time to effect may be a little slower, but the long-term effect seems to be as good or better as other mechanisms of action.”
The drug’s real place could be in early disease, Dr. Hanauer said. “If this is truly an effective and safe agent, the real positioning should be earlier in the disease, before patients are exposed to steroids and other immune suppressants, or biologics that have an infection risk.”
Celgene funded the study. Dr. Sandborn has received funding from Receptos and Celgene and consulted for both companies. Dr. Hanauer has consulted with Receptos, Celgene, Pfizer, Jansen, and AbbVie.