Quince Therapeutics (QNCX) The Citizens JMP Life Sciences Conference 2025 summary

Technology and therapeutic approach

• Utilizes autologous red blood cells to encapsulate dexamethasone sodium phosphate, enabling chronic steroid delivery with reduced toxicity risks.

• The encapsulation process, called AIDE, uses a specialized machine and hypotonic/hypertonic solutions to load drugs into red blood cells.

• The technology allows for a controlled release of dexamethasone, maintaining efficacy while avoiding plasma concentration thresholds linked to toxicity.

• The platform is adaptable for other small or large molecules, potentially expanding to additional rare and non-rare disease indications.

Clinical development and trial design

• Lead program is in phase III for Ataxia Telangiectasia (A-T), a rare pediatric genetic disorder with no approved therapies.

• The current trial targets children aged 6–9, the group with the most rapid neurological decline, using monthly dosing over six months.

• The primary endpoint is a subset of the ICARS neurological score, focused on gait and posture, with a 28% difference versus placebo seen in prior studies.

• The trial is under a Special Protocol Assessment with the FDA, allowing for potential approval based on a single positive study.

• About 60% of patients are enrolled, with full enrollment and data readout expected in Q4.

Safety, efficacy, and regulatory insights

• Long-term safety data show no steroid toxicity in children treated monthly for up to 13 years.

• Efficacy in the target age group was significant in prior studies, with a clinically meaningful impact on patient mobility.

• The encapsulated steroid achieves a Cmax above 100 ng/mL, considered necessary for therapeutic effect, with a safe range up to 500 ng/mL.

• Dosing flexibility (21–30 days) is built into the protocol to accommodate patient needs and practical clinic visits.

• The device and process have undergone extensive validation for reproducibility and safety with regulatory agencies in the US and Europe.