Palomar Labs spun out Ariadne Bio to develop AB-300, a clinical-stage non-hallucinogenic serotonin 2A (5-HT2A) receptor agonist targeting apathy in Parkinson’s disease. The venture studio said the program focuses on neuropsychiatric symptom management, where it claims no approved medicine is designed specifically to restore motivation. Ariadne Bio will be led by Palomar founder and managing partner Shlomi Raz as CEO, with Daniel Jeffries, PhD, taking chief development officer responsibilities. The company positioned apathy as a distinct condition from depression, while noting that SSRI therapy may be appropriate for Parkinson’s associated depression without addressing apathy mechanisms. With about 40% of people with Parkinson’s estimated to experience apathy over the course of illness, the spinout targets a high-prevalence non-motor domain where clinical differentiation could matter for patient quality of life and caregiver burden.