Novel SMA Drug Delivery System Gets FDA Greenlight to Expand Trial Enrollment

The FDA has permitted a biotech company to continue enrolling patients for a pivotal clinical trial of its new drug delivery system for spinal muscular atrophy (SMA) patients. The system, called ThecaFlex DRx, allows subcutaneous administration of Spinraza (nusinersen) directly into the cerebrospinal fluid, and aims to replace the current administrative route through lumbar punctures.

SMA, a rare genetic neurodegenerative disorder affecting approximately 1 in 10,000 newborns, is typically fatal for untreated children by age two. Three disease-modifying medicines have transformed the treatment landscape, including Spinraza (nusinersen) and Evrysdi (risdiplam), which doesn't cure SMA but does modify the underlying disease process; and Zolgensma (onasemnogene abeparvovec-xioi), which is a one-time gene replacement therapy.

The drug delivery system’s maker, Alcyone Therapeutics, said in a press release that the FDA approved expanding the clinical trial with an additional 80 SMA patients across 30 centers in the U.S. and Europe, after reviewing data from the first 10 patients implanted with ThecaFlex.

“The initial data and patient feedback are optimistic and a key first step toward developing a less invasive, more accessible procedure that may improve the overall dosing experience for SMA patients and may help optimize hospital resources,” said the clinical trial’s primary investigator, Scellig Stone, MD, PhD, FRCSC of Boston Children’s Hospital, in the release.

Lumbar punctures, currently the standard of care for delivering therapies into the cerebrospinal fluid, are painful procedures that require specialists for anesthesia and radiographic guidance. In contrast, ThecaFlex is an implantable intrathecal catheter, catheter fixation device, and subcutaneous port system. If approved, the device could shift Spinraza administration from specialized visits requiring anesthesia and radiation exposure to an outpatient setting.

The company said that implantation procedures took 1 to 2 hours, with most patients discharged within 24 hours. Post-implantation drug infusions were typically performed in standard exam rooms and took less than 30 minutes.

The trial is part of a collaboration between Alcyone and Biogen, announced in January 2023. Biogen markets Spinraza, which is approved to treat SMA in infants, children and adults in over 60 countries.

Kathrin Meyer, PhD, Alcyone's Chief Scientific Officer, said in the press release that the enrollment approval represents "a tangible step toward our goal of substantially improving treatment experience for patients requiring repeat intrathecal delivery of medications for the treatment of neurological disorders."