What OCA Efficacy Results Mean For Patients
On July 7, Intercept Pharmaceuticals released new results from the continuation of the REGENERATE trial and announced their intent to file a new NDA for obeticholic acid (OCA) in NASH fibrosis. In this conversation, Stephen Harrison leads Jörn Schattenberg, Louise Campbell and Roger Green in examining the new efficacy analysis and exploring what it means for obeticholic acid, both in terms of the drug’s performance and its revised prospects for FDA approval.
After reviewing the four key points from Intercept’s press release, Stephen Harrison kicks off this conversation by looking at a broader efficacy picture than mere regression of fibrosis, to ask what percentage of patients experienced no further progression of fibrosis compared to the placebo group. Stephen notes that the clinical value of simply halting fibrosis progression in an F3 patient is tremendously important because it allows an asymptomatic patient to continue life at its current level of quality. He adds, “we can manage co-morbidities” separately. He goes on to wonder why Intercept did not expand the analysis to include the large number of patients who made it past the 18-month biopsy time point but were not part of the original 2019 efficacy cohort.
At this point, Stephen takes a step back from the actual data to describe how the consensus approach worked on histological reads and to praise the approach for providing clear, simple answers. Jörn Schattenberg picks up the conversation by agreeing with Stephen’s assessment of the consensus approach, which he describes as emulating how colleagues assess challenging cases or histopathology reports in actual practice.
Roger joins the conversation to wonder why the consensus reading process would have the effect of reducing the percentage of patients who improve in the placebo group on one reading but not elsewhere. More important to him, he goes on to agree with the idea that if this agent regresses fibrosis in some cases but halts progression in most or all, it might become a valuable part of a combination therapy that includes other agents with a stronger effect against steatosis than fibrosis.
Thinking from a patient perspective, Louise notes that consensus reads should give the patient greater confidence in the results. In terms of confidence and border reads, Stephen points out that some of the presentations at the recent ILC2022 meeting that drugs that have an impact on NASH might also affect liver volume. (He notes that the open-label cirrhotic cohort of the resmetirom trial MAESTRO-NAFLD 1 also showed spleen volume reduction and an inverse effect on platelet count.) Setting aside the cirrhosis results, he notes that if we start to measure liver volume when conducting biopsies, we can correct estimates of the impact of fibrosis to account for changes in “what we see” based on changes in liver volume. As the conversation ends, he notes that this might be a fruitful topic for future research that can translate into patient treatment.