Quince Therapeutics Inc. (NASDAQ:QNCX) on Thursday plunged almost 90% after the company shared topline results from its pivotal Phase 3 NEAT clinical trial evaluating its lead asset, dexamethasone sodium phosphate encapsulated in autologous erythrocytes (eDSP) for Ataxia-Telangiectasia (A-T).

Ataxia-Telangiectasia is a rare, inherited neurodegenerative disorder caused by mutations in the ATM gene, leading to progressive loss of coordination (ataxia), small, visible blood vessels (telangiectasias) in the eyes/skin, a weakened immune system, and a high risk of cancer.

Data

Quince enrolled a total of 105 participants in the NEAT study, including 83 participants in the six-to-nine-year-old primary analysis population and 22 participants aged 10 years and older.

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) with a p-value of 0.0851.

Furthermore, the study did not meet its key secondary endpoint of improvement in Clinical Global Impression of Severity (CGI-S) measured from baseline to month six, with a p-value of 0.522.

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

Why It Matters

Quince Therapeutics on Wednesday announced the poster presentation of previously published safety data from the long-term treatment of children with Ataxia-Telangiectasia at the British Paediatric Neurology Association 2026.

Long-term treatment with eDSP in children with A-T was associated with stable growth and metabolic parameters without indications of corticosteroid-related toxicities.

Height and weight z-scores stabilized during treatment with eDSP, and no corticosteroid-related linear growth suppression or weight increase were observed. Progressive growth faltering is a typical characteristic in A-T.

No concerns related to glucose homeostasis or adrenal suppression were identified, and no confirmed cases of adrenal insufficiency occurred, although routine monitoring is recommended.

Price Action: QNCX stock is down 2.22% at $0.26 during the premarket session at the last check on Friday, according to Benzinga Pro data.

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