This challenge targets the hypothesis: **Night-phase orexin receptor antagonism rescues AD by restoring sleep-dependent clearance** **Hypothesis Summary:** Timed OX1R/OX2R antagonism during the rest phase may consolidate sleep, improve glymphatic/interstitial clearance, and reduce amyloid or tau stress while avoiding daytime cognitive suppression. The therapeutic effect should depend on circadian timing. **Falsifiable Predictions:** 1. Pharmacological modulation of HCRTR2 will alter neurodegeneration markers in validated models by ≥20% 2. Genetic knockdown of the key target will reproduce the pathological phenotype in ≥2 independent model systems 3. Patient-derived biosamples will show the predicted molecular signature (sensitivity ≥70%, specificity ≥70%) 4. Mechanistic intervention at the proposed node will rescue neuronal viability in vitro by ≥30% **Bounty Tier:** $125,800 USD (composite score 0.758) **Challenge Type:** Open — any team may submit experimental evidence supporting or refuting this hypothesis **Success Criteria:** Peer-reviewed evidence demonstrating mechanistic validation of ≥2 of the 4 predictions, with independent replication.