Bayer announced from the U.S. market following a failed confirmatory study and discussions with the FDA.
In that phase III study ( -- required as a condition of the PI3K inhibitor's accelerated approval -- adding copanlisib to standard immunochemotherapy failed to improve progression-free survival (PFS) in relapsed follicular lymphoma over immunochemotherapy alone.
No new patients should be prescribed copanlisib, according to Bayer, but the company said it's "exploring access options for patients currently receiving Aliqopa who have experienced a favorable response to treatment, whose treating physician supports continuing treatment with Aliqopa, and for whom there may be no suitable alternative treatments available."
The withdrawal of the PI3K inhibitor represents the latest development in FDA's crackdown on the class of drugs. Other PI3K inhibitors -- including umbralisib (Ukoniq) and -- have already been pulled from the market or had indications withdrawn based on safety concerns and a potential overall survival (OS) detriment seen across confirmatory trials.
And last year, the FDA's Oncologic Drugs Advisory Committee voted 16-0 that future applications for PI3K inhibitors in hematologic cancers should be backed by randomized trial data.
The FDA had granted for patients with relapsed follicular lymphoma who had received at least two prior systemic therapies based on tumor shrinkage data from the phase II CHRONOS-1 trial. In that single-arm study, the PI3K inhibitor induced responses in 59% of patients, including complete responses in 14%. The median duration of response was 12.2 months.
In the subsequent phase III CHRONOS-3 trial, adding copanlisib to rituximab improved PFS over rituximab alone in relapsed indolent non-Hodgkin's lymphoma, including patients with follicular lymphoma (21.5 vs 13.8 months; HR 0.52, 95% CI 0.39-0.69, P<0.0001).
But showed no significant benefit in either the overall population (HR 0.87, 95% CI 0.57-1.35) or follicular lymphoma subgroup (HR 0.95, 95% CI 0.52-1.74), and FDA reviewers expressed concern over an early dip in the survival curve for patients in the combination arm.