(Reuters) – More than 40% of patients with moderate to severe ulcerative colitis achieved clinical remission after a year of taking vedolizumab, an experimental drug developed by Japan’s Takeda Pharmaceutical Co, according to data from a pivotal late-stage trial.
The biologic drug met the goals of the phase III trial with highly statistically significant advantages in rates of remission, clinical response and bowel healing compared with placebo, researchers said.
Of the patients taking part in the year-long maintenance study, 44.8% of those who received vedolizumab every four weeks and 41.8% who got the drug every eight weeks were deemed to be in clinical remission at week 52. That compares with 15.9% of those who received a placebo.
In a subset of patients who were not also taking a steroid for their condition, the remission rate was 45.2% for those who received vedolizumab every four weeks compared with 13.9% in the placebo group.
“The maintenance study data are really spectacular,” said Dr. Brian Feagan, the trial’s lead investigator who presented the data on Tuesday at the Digestive Disease Week meeting in San Diego.
“I think this is a pretty exciting result and has big implication for patient care ultimately,” added Dr. Feagan, from the Robarts Research Institute, London, Ontario, Canada. He said he believes the data are strong enough for the drug to gain approval.
Clinical remission was defined as a score of 2 points or less on the 12-point Mayo scale of disease activity. A Mayo score of 6-12 indicates moderate-to-severe disease.
Vedolizumab, which is given intravenously, belongs to a different class of biologic drugs than the TNF blockers widely used to treat colitis and other inflammatory diseases, such as Johnson & Johnson’s Remicade (infliximab) and Abbott Laboratories’ Humira (adalimumab). The drug targets an integrin protein present in a small percentage of white blood cells that have been shown to play a role in controlling inflammation.
The anti-TNF drugs, while highly effective, suppress the immune system and have been associated with infections and other serious complications, such as tuberculosis.
“It would be nice to have a drug that didn’t do that,” Dr. Feagan said. “There was no increased risk of serious infection or any infection over placebo. It’s pretty striking actually.”
Vedolizumab works in a similar way as Biogen Idec’s multiple sclerosis drug natalizumab (Tysabri), which has been associated with progressive multifocal leukoencephalopathy (PML). Dr. Feagan said vedolizumab is more selective and works on the gut and not the brain so is unlikely to carry a similar risk. “It should not have a PML cloud,” Dr. Feagan said.
He said he expects the drug would initially be used after anti-TNF therapy stops working or in patients who cannot tolerate those drugs. But he believes it may eventually supplant TNF blocker therapy.
About 40% of those in the nearly 900-patient study had previously been treated with a TNF blocker, Dr. Feagan said.
In addition to remission rates, researchers looked at the rate of durable clinical response and bowel improvement, or mucosal healing, at week 52.
For those who received vedolizumab every eight weeks, 56.6% had a durable clinical response, such as a significant easing of symptoms, as did 52% who got the drug every four weeks. That compared with 23.8% in the placebo group.
Clinical response was defined as a drop of 3 points on the Mayo scale, at least a 30 percent reduction in the overall score, and significant improvement in rectal bleeding.
The mucosal healing rate at week 52 was 51.6% for vedolizumab once every eight weeks and 56% for every four-week therapy, compared with 19.8% for placebo.
Patients in the study began with a six-week induction phase in which they got an initial 400 mg dose of the drug to start and another 400 mg dose at week 2 before moving into the maintenance phase for the next 46 weeks.