AdComm experts split on whether to approve ChemoCentryx's avacopan

FDA Building 2
Trading in ChemoCentryx shares was halted while the advisory committee was debating avacopan. (FDA)

The question of whether to approve ChemoCentryx’s vasculitis drug avacopan has divided a panel of experts convened by the FDA. Ten experts voted that the benefit-risk profile supports approval, while the other eight voted against authorizing the drug on the strength of the available evidence.

Reviewers at the FDA set the stage for a tough advisory committee for ChemoCentryx by publishing a briefing document that raised concerns with the phase 3 trial at the center of the filing for approval. ChemoCentryx presented another view in its presentation, arguing that avacopan is a major advance for the field and that the data show clinically meaningful benefits.

The questions posed by the FDA split the panelists. On the key benefit-risk question, ChemoCentryx squeaked a narrow win, although there was a report that one of the 10 people who voted yes did so because they misunderstood what was being asked. If that person had voted no, the panel would have split 50:50 on the risk-benefit question.

The experts did return an even split, nine yeses versus nine noes, when asked whether the efficacy data support approval. In terms of safety, 10 panelists said the data support approval, resulting in a narrow victory for ChemoCentryx.

The final decision on whether to approve avacopan rests with the FDA. Typically, the FDA and the advisory committee reach the same conclusion. However, the lack of a big majority for or against the ChemoCentryx drug in the advisory committee votes makes the outcome hard to predict. 

Joyce Kullman, executive director of the Vasculitis Foundation, asked the FDA “take into account the dire situation faced by patients living with this debilitating disease” in a ChemoCentryx statement about the advisory committee vote.

Trading in ChemoCentryx shares was halted while the advisory committee was debating avacopan. Shares in the company tumbled after the FDA released its briefing document earlier this week but recovered somewhat in the run up to the meeting.