Small OCULUS trial finds less retained stomach content after holding one GLP‑1 dose

The OCULUS randomized clinical trial tested whether withholding one scheduled dose of a GLP-1 or combined GLP-1/GIP medicine changed stomach contents at elective upper endoscopy. The planned interim analysis included 60 adults at two U.S. referral centers. Of those participants, 32 entered the withholding group and 28 remained on treatment.

Before enrollment, participants had remained on the same dose for one month or longer. They underwent upper endoscopy with moderate sedation or monitored anesthesia care. The study excluded people with several conditions that could independently affect stomach emptying or procedural risk, including documented gastroparesis, prior foregut surgery, gastric outlet obstruction, and planned general anesthesia.

The main endpoint was clinically significant residual gastric volume. It combined findings that obstructed the examination, caused the procedure to end early, prompted intubation, or led to an aspiration-related event requiring extra monitoring, unplanned treatment, or admission.

The endpoint occurred in one of 32 participants who withheld a dose, or 3.1%, and seven of 28 who continued, or 25.0%. The absolute difference was 21.9 percentage points, with a 90% confidence interval from 7.0 to 36.7 points. Enrollment ended when the interim result crossed the study's prespecified safety boundary.

Among 35 people who had upper endoscopy without colonoscopy, the endpoint occurred in 5.0% of the hold group and 46.7% of the continuation group. None of the 25 participants who also prepared for colonoscopy with a clear-liquid diet met the endpoint. That subgroup observation was based on very small numbers and was not a randomized test of liquid preparation by itself.

Withholding one dose was associated with fewer retained contents

OCULUS adds randomized evidence to a question that has relied heavily on observational data and expert guidance. Under this protocol, withholding one dose was associated with fewer clinically important retained contents at the time of the procedure.

The result can inform discussion among the patient, prescriber, endoscopy team, and anesthesia team. Current multisociety guidance uses an individualized approach because delayed gastric emptying risk, aspiration risk, blood glucose control, treatment indication, dose escalation, symptoms, and the harms of interruption differ among patients.

The small trial does not set universal guidance

The trial does not support a universal instruction to stop every GLP-1 medicine before every procedure. It was small, involved two referral centers, and stopped at an interim analysis. Early stopping can make the apparent treatment difference less stable than a fully enrolled result.

Residual gastric content is a clinically relevant surrogate, but the study was not large enough to determine whether holding a dose prevents rare aspiration injuries. The results also do not establish the best plan for general anesthesia, emergency procedures, dose-escalation periods, symptomatic gastroparesis, or patients excluded from the trial.

Patients should not withhold a diabetes or obesity medicine on their own. The procedural team may recommend continuing treatment, changing diet before the procedure, using ultrasound, modifying anesthesia, delaying the procedure, or holding a dose based on individual risk.