Gamma-linolenic Acid Supplementation Study (GLASS)

Effects of Gamma-linolenic Acid Supplementation on Weight Loss Maintenance in the Virta Treatment

Weight regain following weight loss is common. In rodent models of obesity and pilot studies in humans, increasing membrane arachidonic acid content improves fuel partitioning and prevents weight regain. This study aims to understand the effect of gamma-linolenic acid (GLA) supplementation on weight loss maintenance in Virta Health patients.

Study Overview

• Status: Completed
• Conditions: Weight Trajectory
• Intervention / Treatment: Dietary supplement: gamma-linolenic acid; Dietary supplement: placebo

Detailed Description

The primary purpose of this research is to determine if GLA supplementation reduces weight regain over 24 months in Virta Health patients.

The secondary purpose is to determine the effect of GLA supplementation on diabetes-related outcomes.

• Study Type: Interventional
• Enrollment (Actual): 302
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94105
      • Virta Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age greater than or equal to 18 yrs
• Patients referred to Virta Health by employers or insurers
• Weight loss greater than or equal to 7% of initial weight and current BMI > 25 kg/m2
• Willing to take 3 supplement capsules daily
• Able to understand study procedures and willing to provide informed consent
• English-speaking

Exclusion Criteria:

• Patients who are pregnant or lactating
• Patients who are taking or are prescribed orlistat

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: gamma-linolenic acid (GLA) supplementation; Sonova GLA safflower oil (840 mg GLA per day)	Dietary supplement: gamma-linolenic acid; 3 capsules per day of GLA for 24 months
Placebo Comparator: placebo control; 1500 mg 'light' olive oil per day	Dietary supplement: placebo; 3 capsules per day of placebo for 24 months

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in change in body weight between groups over time	Body weight measured on a calibrated scale. Interim analyses at 12 and 18 months; if greater weight loss is maintained in the GLA compared to placebo group, the study will be unblinded and placebo group participants will cross over to GLA for the remainder of the trial.	0, 12, 18, and 24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference in subjective neuropathy symptoms between groups over time	Michigan Neuropathy Screening Instrument (MNSI) administered every 6 months	0, 6, 12, 18, and 24 months
Difference in health-related quality of life between groups over time	Patient-Reported Outcomes Measurement Information System-29 (PROMIS-29) administered every 6 months	0, 6, 12, 18, and 24 months
Difference in perceived control over eating between groups over time	Eating Loss of Control Scale (ELOCS) administered every 6 months	0, 6, 12, 18, and 24 months
Difference in body image and satisfaction between groups over time	Body Image States Scale (BISS) administered every 6 months	0, 6, 12, 18, and 24 months
Difference in medication prescriptions between groups over time	Prescribed medications obtained from medical record	0, 6, 12, 18, and 24 months
Difference in hemoglobin A1c between groups over time		Approximately 0, 6, 12, 18, and 24 months
Difference in ketones between groups over time	Finger prick ketone values	0, 6, 12, 18, and 24 months
Difference in blood glucose between groups over time	Finger prick glucose values	0, 6, 12, 18, and 24 months

Collaborators and Investigators

• Sponsor: Virta Health
• Investigators: Principal Investigator: Shaminie Athinarayanan, PhD, Virta Health; Study Director: Rebecca Adams, PhD, Virta Health

Study record dates

Study Major Dates

• Study Start (Actual): July 22, 2020
• Primary Completion (Actual): February 13, 2023
• Study Completion (Actual): September 15, 2023

Study Registration Dates

• First Submitted: July 19, 2020
• First Submitted That Met QC Criteria: July 19, 2020
• First Posted (Actual): July 22, 2020

Study Record Updates

• Last Update Posted (Actual): April 24, 2024
• Last Update Submitted That Met QC Criteria: April 22, 2024
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Body Weight; Body Weight Changes; Body-Weight Trajectory; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anti-Inflammatory Agents, Non-Steroidal; Analgesics, Non-Narcotic; Anti-Inflammatory Agents; Antirheumatic Agents; Antimetabolites; Dermatologic Agents; Hypolipidemic Agents; Lipid Regulating Agents; Evening primrose oil
• Other Study ID Numbers: 2019-6

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Identifiers will be removed and data could then be used for future research studies or distributed to another investigator for future research studies without additional informed consent.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No