U.S. FDA Partial Clinical Hold Lifted on IND for EryDel’s Lead Phase 3 Asset EryDex for the Treatment of Ataxia-Telangiectasia

Quince Therapeutics, Inc. (Nasdaq: QNCX), a biotechnology company focused on acquiring, developing, and commercializing innovative therapeutics that transform patients’ lives, today announced that the U.S. Food and Drug Administration (FDA or the “Agency”) has lifted the partial clinical hold on EryDel S.p.A’s Investigational New Drug (IND) application for its lead Phase 3 asset, EryDex. Pending the closing of Quince’s acquisition of EryDel, Quince intends to advance the global Phase 3 NEAT (Neurologic Effects of EryDex on Subjects with A-T) clinical trial evaluating the safety and efficacy of EryDex for the potential treatment of a rare, fatal pediatric neurological disease, Ataxia-Telangiectasia (A-T). Currently, there are no approved treatments for patients with A-T and the market represents a $1+ billion estimated peak sales opportunity.

Dirk Thye, M.D., Quince’s Chief Executive Officer, said, “We are pleased with the FDA’s decision to lift the partial clinical hold related to EryDel’s lead asset, EryDex. We look forward to completing the clinical and regulatory activities necessary to advance EryDex into the Phase 3 NEAT study – with patient enrollment beginning as soon as the second quarter of 2024. Notably, this pivotal trial will be conducted under a Special Protocol Assessment (SPA) that has already been reviewed with the FDA, which should allow for the submission of a New Drug Application (NDA) following completion of this single study, assuming positive results.”

The Agency had requested additional information on extractables and leachables related to a change in plastics utilized in the EryKit. The change in plastic bags and tubing in the EryKit were implemented in order to be compliant with recent European regulations regarding the type of plastics used in various products. The commercial version of the EryKit treatment consumables is already approved for clinical trial use in Europe.

Quince’s acquisition of EryDel is subject to certain regulatory approvals, including the foreign direct investment screening clearance in Italy, and other closing conditions and is expected to close in the fourth quarter of 2023.

About EryDex and the Phase 3 NEAT Trial

EryDex utilizes a unique drug/device combination that enables a fully automated process at the point of patient care for the autologous intracellular drug encapsulation (AIDE) of dexamethasone sodium phosphate (DSP; a pro-drug) into a patient’s red blood cells. Dexamethasone-loaded red blood cells are then re-infused into the patient, resulting in the circulation of controlled, slow release, low doses of dexamethasone, intended to provide efficacious dosing while avoiding the long-term toxicity typically associated with chronic steroid administration.