At a Nov. 16 meeting, the Oncologic Drugs Advisory Committee of the Food and Drug Administration reviewed the reasons for delays in confirmatory trials for pralatrexate (Folotyn) and belinostat (Beleodaq), both now owned by East Windsor, N.J.–based Acrotech. The FDA granted accelerated approval for pralatrexate in 2009 and belinostat in 2014.
“The consensus of the advisory committee is that we have significant concerns about the very prolonged delay and getting these confirmatory studies underway,” said Andy Chen, MD, PhD, of Oregon Health & Science University, Portland, who served as acting ODAC chair for the meeting.
Corporate ownership changes were among the reasons Acrotech cited for the long delays in producing the confirmatory research on pralatrexate and belinostat. Allos Therapeutics won the FDA approval of pralatrexate in 2009. In 2012, Spectrum Pharmaceuticals acquired Acrotech. Spectrum won approval of belinostat in 2014. Acrotech acquired Spectrum in 2019.
The FDA didn’t ask ODAC to take votes on any questions at the meeting. Instead, the FDA sought its expert feedback about how to address the prolonged delays with pralatrexate and belinostat research and, in general, how to promote more timely completion of confirmatory trials for drugs cleared by accelerated approval.
Pralatrexate and belinostat are both used to treat relapsed or refractory peripheral T-cell lymphoma, a rare and aggressive disease affecting about 10,000-15,000 people annually in the United States.
Through the accelerated approval process, the FDA seeks to speed medicines to people with fatal and serious conditions based on promising signs in clinical testing.
The initial pralatrexate and belinostat were based on phase 2, single-arm, monotherapy studies, with about 109 evaluable patients in the key pralatrexate study and 120 evaluable patients in the belinostat study. As is common, these phase 2 tests used measurements of cancer progression, known as the overall response rate.
The FDA then expects companies to show through more extensive testing that medicines cleared with accelerated approvals can deliver significant benefits, such as extending lives. When there are delays in confirmatory trials, patients can be exposed to medicines, often with significant side effects, that are unlikely to benefit them.
For example, the FDA granted an accelerated approval in 2011 for romidepsin for this use for peripheral T-cell lymphoma, the same condition for which pralatrexate and belinostat are used. But in 2021, Bristol-Myers Squibb withdrew the approval for that use of romidepsin when a confirmatory trial failed to meet the primary efficacy endpoint of progression free survival.
At the meeting, Richard Pazdur, MD, who leads oncology medicine at the FDA, urged Acrotech to shorten the time needed to determine whether its medicines deliver significant benefits to patients and thus merit full approval, or whether they too may fall short.
“We’re really in a situation where patients are caught in the middle here,” Dr. Pazdur said. “I feel very bad for that situation and very bad for the patients that they don’t have this information.”