US regulator throws Chemocentryx a debatable lifeline

Delays to US approval action dates are usually thought of as negative, but the one to Chemocentryx’s avacopan arguably provides a glimmer of hope. This complement factor C5a inhibitor had been written off by some analysts after a mixed adcom vote for ANCA-associated vasculitis in May, but yesterday its Pdufa date, which would have fallen today, was delayed until October 7. Chemocentryx rose 7%, so why could this be good news? Because the delay was prompted by the company’s submission of a filing amendment said to address “points raised” during the adcom. This has been interpreted as a sign, however remote, that the FDA is willing to evaluate new data and other arguments in favour of avacopan’s approval. While Wells Fargo said there was still no clear read-through to approvability, Leerink called the development a surprising apparent change in direction from the FDA. Stifel, meanwhile, provided an analysis suggesting that, in fact, Pdufa date extensions over the past six years have usually resulted in approval. Evaluate Pharma sellside consensus of 2026 avacopan revenue of $799m still looks like a long shot, but at least Chemocentryx has avoided a complete response letter for now.