A 12 Week, 3-Period Study to Evaluate the Effects of a Dietary Supplement on Lipid Metabolism

March 11, 2015 updated by: Access Business Group

A Randomized, Double-Blind, 3-Period Crossover Study to Evaluate the Effects of a Dietary Supplement Containing Botanical Extracts on Fasting and Postprandial Lipid Metabolism in Apparently Healthy, Overweight and Obese Individuals

This study will evaluate the effects of encapsulated botanical extracts, previously shown to inhibit the enzyme diacylglycerol-acyltransferase-1 (DGAT-1) in vitro, on fasting and postprandial lipid metabolism during an oral fat tolerance test (OFTT) in apparently healthy, overweight and obese adult men and women.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Medications currently approved for the treatment of obesity act primarily to promote a state of energy balance - by either suppressing appetite or interfering with lipid absorption in the small intestine. Similarly, it may be possible to reduce or inhibit the synthesis of triglycerides (TG) from dietary fat by targeting the activity of diacylglycerol-acyltransferase-1 (DGAT-1) in the enterocytes of the small intestine.

DGAT-1 catalyzes the final step in the biosynthesis of TG and is most abundantly expressed in the small intestine and adipose tissue. DGAT-1 in enterocytes is critical for assembly of TG from fatty acids derived from food intake. Ingested dietary fat is cleaved to monoacylglycerol and free fatty acids by lipases in the gut lumen and these are next taken up by the enterocytes, where they are re-esterified to TG in the postprandial period. TG is eventually released into circulation, primarily transported by chylomicrons. Thus, DGAT-1 plays a critical role in the absorption of dietary fat and inhibition of DGAT-1 has been shown to delay and decrease re-esterification of dietary fats into circulating TG. It is hypothesized that this effect may lead to decreased deposition of excess dietary fat as adipose tissue, perhaps due to increased fatty acid oxidation in the enterocytes.

The potential physiological benefits of DGAT-1 inhibition lead to the development of the potent, selective DGAT-1 inhibitor, AZD7687. Human clinical trials of AZD7687 demonstrated attenuation of postprandial TG excursions, consistent with inhibition of gut DGAT-1. However, this compound has limited, if any, therapeutic potential due to profound gastrointestinal (GI) side effects, particularly diarrhea, nausea, and abdominal cramping which were deemed intolerable. Moreover, no consistent dose-related treatment effects on body weight, glucose or lipid metabolism were found in the small trials which were deemed to be non-representative of the target therapeutic population.

Both cell-free and cellular in vitro models have been used to identify botanical extracts that have potential to inhibit DGAT-1. In a follow-up 7-d parallel arm proof-of-mechanism human clinical trial, each of four lead ingredients (2 g/d) were evaluated for the ability to inhibit the intestinal release of dietary fat into circulation following a high-fat meal challenge using post-prandial TG response as a surrogate marker. Of the four lead botanical ingredients, whole grape extract (WGE) reduced fasting and postprandial TG levels (total area under the curve from 0 to 6 h) by ~ 7% to 8% following a high-fat meal challenge. This demonstration of efficacy, albeit modest, was sufficient to warrant continued exploration. Importantly, only a few subjects reported very mild GI side effects, primarily bloating, in this trial.

Combinations of WGE with other botanical extracts possessing biological activity against supportive secondary mechanisms that might strengthen the overall inhibition of dietary fat release into circulation and fat deposition were then explored. To examine potential synergistic interactions, WGE was combined with other ingredients known to act on complementary biological pathways that converge into a single efficacy outcome; in this case, cellular TG levels. Ingredients that had effects on both glucose and fatty acid metabolism that could ultimately synergize with the DGAT-1 pathway were chosen. The complementary pathway targets chosen for these experiments were Peroxisome-Proliferator-Activated Receptor-gamma Coactivator 1-alpha (PGC1-α) and Sterol Regulatory Element Binding Protein 1c (SREBP1c).

In the cellular DGAT-1 model, grape seed extract (GSE) resulted in a significant inhibition of DGAT-1 activity when combined with WGE. The combination index (CI), a quantitative measure of synergy, indicated a strong synergistic effect (CI = 0.61). Synergy occurred at a 1:1 ratio of WGE to GSE, and at ratios that induced no effect on DGAT-1 activity when either was used alone. The synergy data, together with the proof of mechanism clinical data, forms the basis for conducting the presently proposed clinical trial at a WGE level below that used in the previous study.

Study Type

Interventional

Enrollment (Actual)

93

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Illinois
      • Addison, Illinois, United States, 60101
        • Biofortis

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 70 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. Subject is male or female, 18-70 years of age, inclusive.
  2. Subject has a fasting TG concentration of ≥150 and <500 mg/dL at visit 1b (week -1). One venous retest allowed for 145-149 and 500-550 mg/dL values.
  3. Subject has a body mass index (BMI) of 25.00-34.99 kg/m2 at visit 1b (week -1).
  4. Subject is willing to maintain habitual diet and physical activity patterns during the study period.
  5. Subject has no plans to change smoking habits during the study period, and if a current smoker, subject is willing to refrain from all tobacco products for 1 h prior to all clinic visits in addition to up to 9 h during the test visits.
  6. Subject has a score of 7 to 10 on the Vein Access Scale at screening visit (visit 1b, week -1).
  7. Subject has no health conditions that would prevent him/her from fulfilling the study requirements as judged by the Investigator on the basis of medical history and routine laboratory test results.
  8. Subject understands the study procedures and signs forms providing informed consent to participate in the study and authorization for release of relevant protected health information to the study Investigator.

Exclusion Criteria:

  1. Subject has abnormal laboratory test results of clinical significance at visit 1b (week -1), at the discretion of the Investigator. One re-test will be allowed on a separate day prior to visit 2 (week 0), for subjects with abnormal laboratory test results.
  2. Subject has a history or presence of clinically important endocrine (including type 1 or 2 diabetes mellitus), cardiovascular (including, but not limited to history of myocardial infarction, peripheral arterial disease, stroke), pulmonary (including uncontrolled asthma), hepatic, renal, hematologic, immunologic, dermatologic, neurologic, psychiatric or biliary disorders.
  3. Subject has a history or current GI disorder that, in the judgment of the Investigator, may have the potential to disrupt normal digestion and absorption of dietary fats, including, but not limited to, Crohn's disease, inflammatory bowel disease, irritable bowel syndrome, significant lactose intolerance and/or egg allergy.

  4. Subject has a known genetic predisposition to hyperlipidemia - as diagnosed by a health care professional.

    Subject is a heavy smoker, defined as a history of smoking >1 pack-per-day in the 3 months prior to visit 1b (week -1).

  5. Subject has a history of difficulty swallowing tablets/capsules that could affect ability to consume the study product.Subject has a history or presence of cancer in the prior two years, except for non-melanoma skin cancer.
  6. Subject has extreme dietary habits (e.g., Atkins diet, very high protein, vegetarian), in the opinion of the Investigator.
  7. Subject has had a weight loss or gain >4.5 kg in the 3 months prior to visit 1b (week -1).
  8. Subject has uncontrolled hypertension (systolic blood pressure ≥160 mm Hg or diastolic blood pressure ≥100 mm Hg) as defined by the blood pressure measured at visit 1b (week -1). One re-test will be allowed on a separate day prior to visit 2 (week 0), for subjects whose blood pressure exceeds either of these cut points, in the judgment of the Investigator.
  9. Subject has not been on a stable dose of antihypertensive medication (at least 4 weeks prior to visit 1b, week -1 and for the duration of the study period.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo
Inactive capsules
Dietary supplement: Placebo
Three placebo capsules consumed prior to breakfast each day for 4 weeks
Active Comparator: Low Dose Grape Blend
Low dose grape blend providing 375 mg whole grape extract + 375 mg grape seed extract/d (750 mg total botanical extracts/d).
Dietary supplement: Low Dose Grape Blend
Three low dose grape blend capsules consumed prior to breakfast each day for 4 weeks.
Active Comparator: High Dose Grape Blend
High dose grape blend providing 500 mg whole grape extract + 500 mg grape seed extract/d (1000 mg total botanical extracts/d)
Dietary supplement: High Dose Grape Blend
Three high dose grape blend capsules consumed prior to breakfast each day for 4 weeks.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Fasting triglycerides
Time Frame: Baseline and at the end of each 4 week treatment period for a total of 12 weeks
Change in fasting plasma TG
Baseline and at the end of each 4 week treatment period for a total of 12 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Area under the curve (AUC) for plasma TG
Time Frame: Baseline and the end of each 4 week treatment period for a total of 12 weeks
Change in the total AUC for plasma TG from 0 to 8 hours following a high fat meal challenge.
Baseline and the end of each 4 week treatment period for a total of 12 weeks
Maximal Concentration (Cmax) and time to Cmax (Tmax)
Time Frame: Baseline and at the end of each 4 week treatment period for a total to 12 weeks
Change in Cmax and Tmax for plasma TG for up to 8 hours following a high fat meal challenge.
Baseline and at the end of each 4 week treatment period for a total to 12 weeks
Plasma TG during the OFTT
Time Frame: Baseline and at the end of each 4 week treatment period for a total of 12 weeks
Change in plasma TG at 2, 4, 6, and 8 hours following a high fat meal challenge.
Baseline and at the end of each 4 week treatment period for a total of 12 weeks
Fasting lipoprotein lipids
Time Frame: Baseline and at the end of each 4 week treatment period for a total of 12 weeks
Change in fasting lipoprotein lipids, including high-density lipoprotein cholesterol (HDL-C), non-HDL-C, low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC).
Baseline and at the end of each 4 week treatment period for a total of 12 weeks
Body weight
Time Frame: Baseline and at the end of each 4 week treatment period for a total of 12 weeks
Change in body weight
Baseline and at the end of each 4 week treatment period for a total of 12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Access Business Group

Investigators

  • Principal Investigator: Andrea Lawson, MD, Biofortis; 211 East Lake Street; Addison, IL 60101

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

July 1, 2014

Primary Completion (Actual)

March 1, 2015

Study Completion (Actual)

March 1, 2015

Study Registration Dates

First Submitted

October 15, 2014

First Submitted That Met QC Criteria

February 18, 2015

First Posted (Estimate)

February 19, 2015

Study Record Updates

Last Update Posted (Estimate)

March 12, 2015

Last Update Submitted That Met QC Criteria

March 11, 2015

Last Verified

March 1, 2015

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • BIO-1403

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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