BOSTON (TheStreet) -- Bluebird Bio (BLUE) and Intercept Pharmaceuticals (ICPT) have reached separate agreements with regulators on the design of pivotal clinical trials intended to get their respective gene therapy and fatty liver disease drugs approved.
For BlueBird, the path to European approval for its gene therapy in beta-thalassemia, a rare blood disorder, could be relatively short and may not involve new clinical trials.
Intercept reached an agreement with U.S. and European regulators on the design for a single (but large) phase III trial for obeticholic acid (OCA) in patients with nonalcoholic steatohepatitis (NASH). NASH is commonly referred to as fatty liver disease because patients literally have livers which are inflamed and enlarged due to the accumulation of fat. In more advanced NASH patients, the liver becomes fibrotic, which can lead to cirrhosis.
The phase III study will enroll 2,500 patients with NASH and liver fibrosis. The patients will be treated with either a low and high dose of OCA or a placebo. After 72 weeks of treatment, an interim analysis on 1,400 patients will be performed on co-primary endpoints: first, a decrease in liver fibrosis by at least one stage; and second, resolution of NASH with no worsening of fibrosis.
The efficacy endpoints to be used in the phase III study are similar to those used in Intercept's successful phase II study. In that older study, OCA demonstrated a statistically significant reduction in liver fibrosis compared to placebo. OCA also improved NASH resolution compared to placebo, but the benefit was not statistically significant.