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.
Other Obeticholic Acid (OCA) Questions
Stephen starts this conversation by asking the group how important it is for a drug (in this case, obeticholic acid) to show a combined endpoint of fibrosis improvement and NASH resolution. He notes this is a tougher standard to hit but notes that it might be quite important.
Jörn describes this comment as a “good point” that probably was not addressed due to the low level of NASH resolution when viewed as a primary endpoint. Louise says she would need to know more about the diets patients were on while in the trial given the effect diet can have on liver fat. She then goes on to say that one question she would like to have answered is how many patients needed counseling on their pruritus to stay in the study and what exact steps did researchers take to keep these patients in. She points out that knowing the steps necessary to maintain patient adherence is vitally important to caregivers but rarely reported for trials, if ever.
Roger makes two points. His first basically supports Jörn’s comment that the low level of NASH resolution as a primary endpoint virtually guarantees that the number of patients achieving the dual endpoint will be minimal at best. His second harkens back to Stephen’s earlier point about including a larger post-18 month patient pool in the efficacy analysis. To Roger, it appears that Intercept made the sound commercial decision to reveal only the data necessary to generate the analyses necessary for approval. It felt to him as if Intercept assessed the least risky way to refute each point in the CRL, and then did only the analyses necessary to refute points successfully. In essence, Roger describes the analysis as a way to de-risk the drug and believes they appear to have done so effectively.
At this point, Stephen shifts direction. He gives Intercept “accolades…they didn’t give up. They persevered. They continued to drive forward and they added three different adjudication committees.” And while he believes there is more analysis to be done, he describes the contents of the press release as “a very, very positive implication for the field” and “give[s] it two thumbs up.”
After Roger concurs, Stephen goes back to Louise’s questions about pruritus and notes that the methodology for evaluating pruritus might have produced overstated results. In essence, the investigator asked patients whether they were experiencing pruritus at every visit, an approach Stephen and Jörn believe was likely to produce an overstatement on itching. Stephen continues this line of thinking to note that investigators were forced to discontinue therapy under certain pruritus reports. As the conversation ends, he notes that he is far more interested in hepatic effects.
