Quince Stock Tumbles and Board Members Resign After Phase 3 Miss in A-T

Rare Daily Staff

Quince Therapeutics said its lead experimental therapy failed to meet the primary and secondary endpoints in a Phase 3 clinical trial evaluating the treatment in patients with the rare neurodegenerative disorder ataxia-telangiectasia.

News of the results sent shares of Quince tumbling to as low as 16 cents on Jan. 30 after opening the previous day at $3.14.

In a filing with the U.S. Securities and Exchange Commission, the company said that five of its eight directors resigned on Jan. 30, including Rajiv Patni, Luca Benatti, Margi McLoughlin, Una Ryan, and June Bray, effective Jan. 30, 2026.

Ataxia-telangiectasia (A-T) is an inherited disorder caused by mutations in the ATM gene, which is responsible for cell homeostasis and cell division functions, including double-stranded DNA repair. Typically, A-T is diagnosed before the age of 5, as children begin to develop an altered gait and fall with greater frequency.

Neurological symptoms worsen over time, and patients with A-T frequently become wheelchair-bound by adolescence. The teenage years for patients with A-T are typically marked by repeated infections, pulmonary impairment, and malignancies. The median lifespan is approximately 25 to 30 years, with mortality often due to infections and malignancy.

The company’s experimental therapy, eDSP, consists of dexamethasone sodium phosphate (DSP) encapsulated in a patient’s own red blood cells. DSP is a corticosteroid well known for its anti-inflammatory properties as well as its dose-limiting toxicity due to adrenal suppression. The eDSP system is designed to deliver the efficacy of corticosteroids while reducing or eliminating the significant adverse effects associated with chronic corticosteroid use.

eDSP leverages Quince’s proprietary Autologous Intracellular Drug Encapsulation (AIDE) technology platform, a novel drug-device combination that uses an automated process to encapsulate a drug into a patient’s own red blood cells.

Red blood cells have several characteristics that make them potentially effective vehicles for drug delivery, including better tolerability, enhanced tissue distribution, reduced immunogenicity, and prolonged circulating half-life. Quince’s AIDE technology is designed to harness these benefits to allow for the chronic administration of drugs limited by toxicity, poor biodistribution, suboptimal pharmacokinetics, or immune response.

In the NEAT study, the company’s pivotal Phase 3 international, multicenter, randomized, double-blind, placebo-controlled trial, the primary endpoint—change from baseline to the last efficacy visit at month six using the rescored modified International Cooperative Ataxia Rating Scale compared to placebo—did not reach statistical significance. The mean change from baseline to month six was 0.94 in the active arm compared to 2.24 in the placebo arm (difference, -1.30). The study also failed to meet its key secondary endpoint measuring improvement in the Clinical Global Impression of Severity (CGI-S) from baseline to month six.

eDSP was generally well tolerated, with no clinically meaningful safety concerns identified. The most common adverse events reported in the eDSP arm included pruritus and pyrexia.