Palomar Labs, rebranded from Negev Labs, spun out Ariadne Bio to develop AB-300, a clinical-stage serotonin 2A (5-HT2A) receptor agonist intended to treat apathy in people with Parkinson’s disease. The venture studio said AB-300 is designed as a non-hallucinogenic program, targeting motivation loss—a disabling non-motor feature with limited treatment options. Ariadne Bio appointed Shlomi Raz as CEO and Daniel Jeffries as chief development officer. The company estimated that apathy affects roughly 40% of patients over the course of Parkinson’s, with higher rates reported in mid-to-late disease stages. The launch sets up a focused clinic path that differentiates apathy from depression, noting that existing antidepressant approaches such as SSRIs are not necessarily aligned with the apathy symptom profile. Palomar framed the spinout around candidates with prior human validation, aiming to reduce development risk by leveraging known tolerability and efficacy signals. For the neuropsychiatry landscape, the decision highlights ongoing demand for mechanisms that can improve motivation without the psychiatric adverse-effect burdens associated with some receptor agonists.