Abstract Schedule 1 Therapeutics (S1Tx) is developing optimized cannabinoid therapeutics for FDA approval in migraine, the second most debilitating disease worldwide. The goal of this SBIR is to obtain IND clearance from FDA to begin a phase 1 clinical trial of S1Tx’s lead candidate S1-220 (100:1 CBD:THC fixed-dose combination) which demonstrated efficacy in preclinical migraine models in the company’s Phase 1 STTR, with no adverse effects. Migraine has a 15% global prevalence and is a leading cause of global disability. Current treatments are not sufficient with at most half of patients relieved from debilitating pain. Evidence supports potential efficacy of Δ9- tetrahydrocannabinol (THC) and cannabidiol (CBD) in migraine. However, these studies suffer from lack of proper controls or do not take a drug design approach to optimizing the combination as a migraine treatment. S1-220 will treat migraine via multiple novel mechanisms and meet the needs of millions for whom current therapies are ineffective or pose unacceptable risks. Rapid administration supports rescue of acute attacks, and S1-220 is an alternative to unmonitored self-medication of cannabis, which may pose health, safety, and legal harms to patients if misused. This SBIR will advance a novel therapeutic and will validate our model to develop optimized cannabinoid therapeutics for large pain and CNS disorders. S1-220 was identified in a Phase I STTR with partners at University of Iowa (Russo). This Phase II SBIR will select human doses for formulation into a sublingual spray that meets FDA requirements for a phase 1 clinical trial. Aim 1. Escalate S1-220 dosing (100:1 CBD:THC) in preclinical CGRP and SNP migraine models and assays (three migraine symptom and three adverse effect assays). Compare pharmacokinetic (PK) levels of THC, 11-OH-THC, THC-COOH, CBD, 7-OH- CBD, and 7-COOH-CBD with behavioral responses for use as a basis for allometric scaling to set targets for equivalent human PK levels and corresponding human doses of S1-220 for a phase 1 clinical trial. Aim 2. Design and manufacture a drug product suitable for use in a phase 1 clinical trial. Pre-formulation (solubility, stability) and formulation (drug-drug and drug-device compatibility) studies with S1-220 will be conducted to design and manufacture a sublingual spray clinical dosage form suitable for use a phase 1 trial. Aim 3: Synthesize findings from Aim 1 and Aim 2, and follow FDA pre-IND meeting guidance (2021) to prepare a phase 1 clinical protocol, establish a scientifically appropriate case for S1-220 safety, and submit an IND application for FDA clearance to begin a phase 1 clinical trial. Of ~40M migraine suffers in the U.S. (a conservative 12% prevalence), ~22M are diagnosed. Of these, ~ 7.3M are prescribed the standard of care triptans, of which > 80% have discontinued at 2 years (~6.2M). S1-220 is targeting 25% of these failures(~1.55M), at $1,460 annual spend per patient (~50% of gepant and ditan price), yield...