Prebiotic Clinical Trial Services for Gut Health Supplements

Non-microbial gut health supplements are products that use prebiotic fibers, plant extracts or digestive enzymes to support the function of the gastrointestinal tract. A prebiotic is a component that the body cannot digest in the small intestine; when it reaches the large intestine, it is selectively fermented by microorganisms, changing the composition or activity of the gut microbiota in a way that benefits health (Slavin, 2013). A prebiotic clinical trial for these products measures gastrointestinal symptoms and bowel habits in volunteers who take the actual product and compares them with a group that receives a placebo.

The market for these dietary supplements continues to grow in Thailand and worldwide, as consumers become more aware that gut health is linked to overall well-being. Brand owners who want to state that a product “supports digestion” or “helps maintain regular bowel movements” must have scientific evidence for that statement, and food advertising must comply with the Food Act B.E. 2522 (1979), including advertising approval where the law requires it.

Measuring gastrointestinal outcomes is complex because they have both subjective dimensions, such as abdominal discomfort and bloating, and more objectively measurable dimensions, such as stool form, which serves as a proxy for the time food takes to pass through the intestine (transit time). VISBIO Co., Ltd. provides study design, project management and project coordination for clinical studies that combine both dimensions, working with a network of partner clinical research sites and hospitals and using internationally accepted assessment tools under Good Clinical Practice (GCP). The service runs from planning the study protocol to the final report, for sponsors in Thailand and abroad.

This service covers non-microbial gut health supplements, such as prebiotic fibers, plant extracts and digestive enzymes. Probiotic and postbiotic products are covered by a separate clinical trial service.

Under the Food Act B.E. 2522 (1979), the approval of dietary supplements by the Thai Food and Drug Administration (Thai FDA) focuses mainly on product safety and quality and does not confirm clinical efficacy. This gap matters a great deal for products that want to communicate digestive benefits, because the food serial number (Thai FDA number) on the label does not show that the product has the stated effect on the gastrointestinal tract.

This directly affects brand owners, especially in a market where gut health claims are widespread and consumers are starting to ask whether these products “really work”. At the same time, some modern trade retailers and export partners have started to request supporting scientific documents before they list a product.

A clinical trial is designed to generate exactly this empirical evidence, by comparing gastrointestinal symptom scores between a group that receives the product and a group that receives a placebo under controlled conditions in line with GCP. The resulting data support product development and evidence-based communication.

This product category covers several ingredient groups, and each works through a different mechanism. Prebiotic fibers cannot be digested by the body, but they feed beneficial microorganisms in the gut. Slavin (2013) concludes that dietary fiber contributes to regular bowel function by increasing stool weight and softness. Prebiotics such as inulin, fructooligosaccharides (FOS) and galactooligosaccharides (GOS) are fermented by microorganisms in the large intestine, with bifidobacteria and lactobacilli as the main targets, and changes in bifidobacteria are the more pronounced.

Herbs studied for gastrointestinal effects, such as ginger (Zingiber officinale), aloe vera (Aloe vera) and artichoke (Cynara scolymus), act through different mechanisms. For example, a randomized, double-blind study in 24 healthy volunteers found that 1,200 mg of ginger accelerated gastric emptying and increased antral contractions, but found no difference in gastrointestinal symptoms compared with placebo (Wu et al., 2008). Results like this show that physiological changes do not always change the symptoms consumers perceive, which is why choosing endpoints that match the claim is important.

The main challenge in designing studies for this category is selecting endpoints that reflect both subjective and objective symptoms and that match the claim the brand owner wants to substantiate. Svedlund et al. (1988) developed the 15-item Gastrointestinal Symptom Rating Scale (GSRS), which is commonly grouped into five symptom clusters. Lewis and Heaton (1997) showed that the seven-type Bristol Stool Form Scale (BSFS) correlates with intestinal transit time and can be used to monitor changes in bowel function. A well-designed protocol is therefore the most important starting point.

Every study follows GCP and takes into account the particular nature of gastrointestinal outcomes, which require both patient-reported outcome measures (PROMs) and objective endpoints. VISBIO designs the study and manages it from planning through to delivery of the report, while volunteers are recruited and cared for by the physicians and investigators of the research site responsible for the study.

Step 1: Consultation and protocol design

VISBIO analyzes the product’s characteristics, the outcomes the company wants to claim and the product’s objectives together with the investigators of the partner research site to define a suitable study plan, including the choice of a primary endpoint for gastrointestinal symptoms. This step covers volunteer inclusion/exclusion criteria that suit the claim and a sample size estimation that gives adequate statistical power.

Step 2: Approval from a human research ethics committee

Before any data are collected, the protocol and the informed consent documents must be approved by a human research ethics committee (Institutional Review Board, IRB) in every case. VISBIO coordinates the preparation of the complete document set with the site’s investigators and follows up on the revisions requested by the committee until approval is granted.

Step 3: Volunteer recruitment and screening

Once approval is granted, the research site responsible for the study recruits and screens volunteers according to the criteria in the protocol. The site’s physicians and investigators make sure that every volunteer receives complete information, gives written informed consent and passes health screening before joining the study. VISBIO coordinates schedules and project readiness between the sponsor and the research site.

Step 4: Study conduct and data collection

Volunteers receive the product, and data are collected at the time points set in the protocol using standard assessment tools accepted in international clinical research, such as the Gastrointestinal Symptom Rating Scale (GSRS) (Svedlund et al., 1988), the Bristol Stool Form Scale (BSFS) (Lewis & Heaton, 1997) and a food diary, together with adverse event recording throughout the study. The site’s investigators assess and safeguard volunteer safety, while VISBIO, as project manager, monitors progress and data completeness.

Step 5: Data analysis and reporting

All data are analyzed statistically according to the statistical analysis plan (SAP) set at the design stage and summarized in a full scientific report in an internationally used format. VISBIO coordinates the analysis and delivers the report to the sponsor. The report supports product development and evidence-based communication.

This service is designed for dietary supplements in various formats that aim to communicate gut health benefits. Examples of suitable ingredient types include:

The examples in the table are ingredient types found in the dietary supplement market. Each ingredient used in products sold in Thailand must meet Thai FDA requirements. For example, aloe vera in dietary supplements must use the gel from the leaf, and leaf parts containing hydroxyanthracene derivatives are not permitted in food.

Clinical study evidence is not just a regulatory document. It is a strategic asset that owners of gut health brands can use to create value in several ways.

Premium product positioning

Products backed by clinical study data can be credibly positioned in the premium segment. GSRS and BSFS data measured in the product group compared with a control group give the product’s value proposition a factual basis and set it apart from competitors without such data.

Negotiating with modern trade and e-commerce channels

Many e-commerce platforms and modern trade buyers in the health category request supporting scientific documents. A clinical study report prepared under GCP makes negotiations and listing in these channels smoother.

Reducing legal risk and expanding into export markets

Gut health claims backed by clinical study evidence reduce the risk that advertising will be considered exaggerated under the Food Act B.E. 2522 (1979). A study designed and reported in line with international practice is also an important part of preparing for export markets, although each country has its own requirements.

Using scientific data in communication

Data actually measured in a clinical study can be used across several communication channels. Any use in advertising must first obtain advertising approval from the Thai FDA as required by law.

1. Dietary supplements sold in Thailand must be approved by the Thai FDA and hold a food serial number (Thai FDA number) before the study starts. For products from international sponsors, VISBIO assesses the legal requirements with the research site on a project-by-project basis.
2. VISBIO and the research site design the study plan specifically for each product and its claims.
3. Every study must be approved by a human research ethics committee before it starts, without exception.

For brands that want to build evidence at every level, VISBIO supports laboratory work such as protease enzyme content analysis for digestive enzyme products, beta-glucan content analysis for fiber products and cell-based (in vitro) efficacy testing, through to clinical studies in volunteers. GCP applies to studies in humans, while laboratory work follows the test method of each assay. Planning every level of evidence with a single coordinator keeps the data at each stage consistent and free of gaps. Clinical trial services for other dietary supplements are described on the knee health supplement clinical trial page.

How does this service differ from a probiotic clinical trial?

This service covers products that do not contain live microorganisms, such as prebiotic fibers, plant extracts and digestive enzymes. Probiotic and postbiotic products are covered by a separate clinical trial service, because those studies must be designed around the specific microbial strain.

What is a prebiotic?

A prebiotic is a component that the body cannot digest in the small intestine. When it reaches the large intestine, it is selectively fermented by microorganisms, changing the composition or activity of the gut microbiota in a way that benefits health. Examples include inulin, FOS and GOS.

Which tools are used to measure outcomes?

Standard assessment tools such as the Gastrointestinal Symptom Rating Scale (GSRS), the Bristol Stool Form Scale (BSFS) and a food diary, together with adverse event recording throughout the study. Endpoints are chosen to match the claim of each product.

Does a product with a Thai FDA number still need clinical data?

The Thai FDA number for a dietary supplement is based mainly on an assessment of safety and quality. It does not confirm that the product has the stated effect on the gastrointestinal tract. If you want to communicate such benefits, clinical data provide supporting evidence, and advertising must still comply with food law.

What is VISBIO’s role, and who looks after the volunteers?

VISBIO designs the study and provides project management and coordination with a network of partner clinical research sites and hospitals. Volunteers are recruited and cared for by the physicians and investigators of the site responsible for the study.

Do study results guarantee advertising approval?

No. Study results support product development and evidence-based communication. Use on labels or in advertising must comply with the law and obtain approval from the relevant authorities where the law requires it. VISBIO does not guarantee study outcomes or regulatory decisions.

If you are interested in a clinical trial for your gut health supplement, contact VISBIO for a free initial consultation through the following channels:

• Contact form: https://visbio.co.th/en/contact-us/
• LINE Official Account: @visbio
• Email: service@visbio.co.th
• Phone: 098-635-4197 (+66 98 635 4197)
• Timeline: please ask our team directly.

See all clinical trial services on VISBIO’s clinical trial page.

• VISBIO’s role: VISBIO designs studies and provides project management and project coordination with a network of partner clinical research sites and hospitals, for sponsors in Thailand and abroad. Volunteers are recruited and cared for by the physicians and investigators of the site responsible for the study.
• Research ethics: Every study in humans starts only after approval by a human research ethics committee and is conducted in line with Good Clinical Practice (GCP). All volunteers give informed consent after receiving complete information.
• Drugs and herbal medicines: Studies must follow the requirements of the Thai Food and Drug Administration (Thai FDA) that apply to the product. The sponsor, the research site and VISBIO plan these steps together from the start of the project.
• Use of results: Study results support product development and evidence-based communication. Use on labels or in advertising must comply with the law for each product type, with approval from the relevant authorities where the law requires it. VISBIO does not guarantee study outcomes or regulatory decisions.
• Foods and dietary supplements: Study results are not a claim that a product diagnoses, treats, cures, mitigates or prevents any disease.
• Timeline: This depends on the study design and the approval process. Please ask our team directly.

References:

1. Lewis, S. J., & Heaton, K. W. (1997). Stool form scale as a useful guide to intestinal transit time. Scandinavian Journal of Gastroenterology, 32(9), 920–924. https://doi.org/10.3109/00365529709011203
2. Slavin, J. (2013). Fiber and prebiotics: Mechanisms and health benefits. Nutrients, 5(4), 1417–1435. https://doi.org/10.3390/nu5041417
3. Svedlund, J., Sjödin, I., & Dotevall, G. (1988). GSRS—A clinical rating scale for gastrointestinal symptoms in patients with irritable bowel syndrome and peptic ulcer disease. Digestive Diseases and Sciences, 33(2), 129–134. https://doi.org/10.1007/BF01535722
4. Wu, K.-L., Rayner, C. K., Chuah, S.-K., Changchien, C.-S., Lu, S.-N., Chiu, Y.-C., Chiu, K.-W., & Lee, C.-M. (2008). Effects of ginger on gastric emptying and motility in healthy humans. European Journal of Gastroenterology & Hepatology, 20(5), 436–440. https://doi.org/10.1097/MEG.0b013e3282f4b224