Quince Therapeutics to Acquire A-T Therapy Developer EryDel

Quince Therapeutics said it agreed to acquire privately held EryDel, which has a lead experimental program in phase 3 for the rare neurological disease ataxia-telangiectasia, in a stock swap with the potential for cash milestone payments.

The company plans to enroll the first patient in a global phase 3 trial of its experimental ataxia-telangiectasia (A-T) therapy EryDex in the second quarter of 2024 with a submission seeking marketing approval in the United States targeted by end of 2025. EryDel has developed an autologous intracellular drug encapsulation technology, which it uses in its treatment for A-T.

A-T is a rare genetic disease that causes progressive neurodegeneration from early infancy. It is caused by mutations in the ataxia telangiectasia mutated (ATM) gene. There is no established therapy available. ATM encodes a PI3Kinase protein, which plays a pivotal role in response to DNA damage and cell cycle control. A-T is a multi-systemic disorder, mainly involving the nervous and immune systems, but also predisposing patients to develop cancer. Specific features include progressive ataxia of the trunk and limbs, involuntary movements, oculomotor apraxia, difficulties with speech and swallowing, and peripheral neuropathy. Other clinical features of patients with the classical phenotype include oculocutaneous telangiectasia, immunodeficiency with recurrent respiratory tract infections, radiosensitivity, and an increased incidence of cancer.

EryDel’s EryDex system uses red blood cell technology to encapsulate small and large molecule therapeutics in patients’ red blood cells. In the case of A-T, the company is using its EryDex system to deliver dexamethasone sodium phosphate, a steroid, by encapsulating the drug into red cells taken from the patient’s own blood, which are then re-infused into the patient. EryDex has received Orphan Drug designation for the treatment of A-T both from the U.S. Food and Drug Administration and the European Medicines Agency. EryDel recently completed a pilot phase 2 trial in A-T patients that demonstrated the statistically significant efficacy of EDS on both primary and secondary outcome measures.

Upon completion of the transaction, EryDel stockholders will own approximately 16.7 percent of the combined company (subject to downward adjustment) and will be entitled to up to $485 million upon the achievement of development, regulatory, and commercial milestone payments, with no royalties.

The transaction has been unanimously approved by the boards of both companies. It is subject to certain regulatory approvals and other closing conditions and is expected to close in the third quarter of 2023.

“EryDel’s proprietary AIDE technology enables the autologous intracellular encapsulation and delivery of dexamethasone in a controlled, slow-release manner that has the potential to allow chronic administration of steroids over many months or years with a favorable safety profile,” said Dirk Thye, CEO of Quince. “This represents a tremendous opportunity to target not only A-T, but also the potential to expand into several debilitating rare diseases where chronic steroid treatment is the standard of care—or could be in the absence of long-term steroid toxicity.

Photo: Dirk Thye, CEO of Quince