FDA hits Ziopharm CAR-T trial with clinical hold

The FDA has placed a clinical hold on Ziopharm Oncology’s phase 1 CAR-T trial. Ziopharm wants to run the study to assess CAR-T cells manufactured at the point of care, but the FDA is demanding more chemistry, manufacturing and control (CMC) information before allowing it to proceed.

Boston-based Ziopharm sees its point-of-care CAR-T production technology eliminating the complex, expensive supply chain and facilities required to manufacture first-generation therapies from Gilead and Novartis. Instead of shipping cells from hospitals to production plants and back again, all processing will take place within two days at the healthcare center, thereby driving down treatment costs.

The first trial to use the technology has hit a snag, though. Ziopharm wants to start dosing patients with a CD19 CAR-T produced at the point of care later this year. But the FDA is demanding more CMC details, potentially delaying the start of the study.

Ziopharm CEO Laurence Cooper, M.D., Ph.D., said the company knows what is needed to address the causes of the clinical hold and will respond to the FDA "in a timely manner." The company is yet to share further details about why the FDA is pumping the brakes on the program, or to commit to a target date for clearing the regulatory blockade.

Shares in Ziopharm fell 12% in premarket trading following the release of the news. The drop reflects the readthrough from the hold for the prospects of a technology that is central to Ziopharm’s plans.

Until recently, Ziopharm’s top priority was to get inducible adenoviral vector Ad-RTS-hIL-12 into a pivotal brain cancer trial. That changed last month when a stubborn CMC problem prompted the biotech to switch gears, putting the phase 3 on ice indefinitely to step up its focus on point-of-care CAR-T and other early-phase programs.

Successful development of a point-of-care CAR-T would upend the nascent market by cutting costs and turnaround times. But, as with all early-phase programs of novel technologies, there are doubts about whether the approach will yield a safe, efficacious therapy. The FDA delay—and lack of details about it—adds to those doubts.