This is a Phase 2, factorial-designed, randomized, double-blind, placebo-controlled, parallel-cohort study to be conducted in 324 adult male and female participants who are ≥ 55 years of age and undergoing cataract extraction with lens replacement. An additional 3 participants per site (first 3 participants enrolled per site) will be considered sentinel participants for the purpose of ensuring safety and that logistical and operational challenges that may occur during the study are identified and mitigated. Sentinel participants will be evaluated for safety but not for efficacy. The study aims to evaluate the efficacy and safety of MELT-300 and the contribution of midazolam and ketamine components for procedural sedation prior to cataract surgery. In the study, eligible study participants will be randomly assigned (1:1:1:1 ratio) to one of the following treatments: MELT-300 (3 mg/50 mg), midazolam 3 mg, ketamine 50 mg, and placebo sublingual tablet 30 (± 5) minutes prior to the anticipated start of surgery (defined as instillation of topical ocular anesthetic drops [i.e., proparacaine]) without food or water in the operating room. At the time of dosing, participants will be instructed to hold the tablet under their tongue until it is completely dissolved and to not swallow or chew the tablets. The study duration will be up to 35 days, including 28 days for screening and 7 ± 2 days after surgery.~Efficacy assessments will be performed after study medication administration before surgery, intraoperatively, and postoperatively on Day 1 (end of surgery defined as drape removal). Efficacy assessments will include assessments of sedation and intraoperative pain, the need for rescue medication for sedation or pain, and the ability to complete the surgery. Safety will be monitored at baseline, intraoperatively, postoperatively on Day 1, on the day after surgery (Day 2, via a phone call), and at 1 week (Day 8 ± 2 days) after dosing of study medication. Safety assessments will include monitoring of AEs, vital sign measurements, physical examinations, and 12-lead ECGs. Exploratory endpoints are postoperative pain as measured by the NPRS prior to discharge, 6 hours +/- 30 minutes after the end of surgery on Day 1 and on Days 2 (the day after surgery), the percentage of participants with concomitant medication opioid use, and average opioid consumption on Day 2 and participant likelihood of wanting study drug again for second cataract surgery as measured by an 11-point Likert scale on Day 2.
The primary purpose of the study is to evaluate the efficacy and safety of MELT-300 (Midazolam and Ketamine Sublingual Tablets) and the contribution of midazolam and ketamine components to sedation and during the surgery or ocular analgesia in participants undergoing cataract surgery with lens replacement.