CLINICAL TRIALS PROFILE FOR ORLISTAT

505(b)(2) Clinical Trials for orlistat

This table shows clinical trials for potential 505(b)(2) applications. See the next table for all clinical trials

Trial Type	Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
New Dosage	NCT01550926 ↗	A Study to Assess the Pharmacologic Equivalence of Two Orlistat Dosage Forms	Completed	GlaxoSmithKline	Phase 1	2009-02-01	The purpose of this study is to determine whether a new dosage form and dose of orlistat is equivalent to the currently marketed form.

All Clinical Trials for orlistat

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00001723 ↗	Safety and Efficacy of Xenical in Children and Adolescents With Obesity-Related Diseases	Completed	Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)	Phase 2	1998-05-01	Obesity is a condition affecting one-third off the U.S. population and is a major risk actor for the development of Type 2 diabetes, hyperlipidemia (increased levels of fat in the blood), hypertension (high blood pressure), and other disorders of the heart and lungs. Individuals with the onset of obesity during childhood or adolescence are at an increased risk of obesity-related, diseases, both during adolescence and later in adult life. African American girls and women are at an increased risk for obesity, and have substantial rates of obesity-related diseases and causes of death. Further, many African American adult women fail to respond to many of the therapeutic approaches used to treat obesity. At present there are no medical therapies proven effective for the correction of severe obesity in children or adolescents. One medication that may have a favorable risk-benefit ratio in pediatric populations is Orlistat (Xenical, Hoffmann LaRoche). Orlistat works by preventing the action of enzymes in the digestive process, interfering with the absorption of approximately 1/3 of the fat eaten in the diet. Xenical appears to be effective for reducing weight and obesity-associated diseases in obese adults. Researchers propose to determine the safety, tolerability, and efficacy of Xenical in 12-17 year old severely obese African American and Caucasian children and adolescents who have one or more obesity-related disease (hypertension, hyperlipidemia, sleep apnea, hepatic steatosis, insulin resistance, impaired glucose tolerance, or Type 2 diabetes).
NCT00001723 ↗	Safety and Efficacy of Xenical in Children and Adolescents With Obesity-Related Diseases	Completed	Roche Pharma AG	Phase 2	1998-05-01	Obesity is a condition affecting one-third off the U.S. population and is a major risk actor for the development of Type 2 diabetes, hyperlipidemia (increased levels of fat in the blood), hypertension (high blood pressure), and other disorders of the heart and lungs. Individuals with the onset of obesity during childhood or adolescence are at an increased risk of obesity-related, diseases, both during adolescence and later in adult life. African American girls and women are at an increased risk for obesity, and have substantial rates of obesity-related diseases and causes of death. Further, many African American adult women fail to respond to many of the therapeutic approaches used to treat obesity. At present there are no medical therapies proven effective for the correction of severe obesity in children or adolescents. One medication that may have a favorable risk-benefit ratio in pediatric populations is Orlistat (Xenical, Hoffmann LaRoche). Orlistat works by preventing the action of enzymes in the digestive process, interfering with the absorption of approximately 1/3 of the fat eaten in the diet. Xenical appears to be effective for reducing weight and obesity-associated diseases in obese adults. Researchers propose to determine the safety, tolerability, and efficacy of Xenical in 12-17 year old severely obese African American and Caucasian children and adolescents who have one or more obesity-related disease (hypertension, hyperlipidemia, sleep apnea, hepatic steatosis, insulin resistance, impaired glucose tolerance, or Type 2 diabetes).
NCT00001723 ↗	Safety and Efficacy of Xenical in Children and Adolescents With Obesity-Related Diseases	Completed	Jack Yanovski	Phase 2	1998-05-01	Obesity is a condition affecting one-third off the U.S. population and is a major risk actor for the development of Type 2 diabetes, hyperlipidemia (increased levels of fat in the blood), hypertension (high blood pressure), and other disorders of the heart and lungs. Individuals with the onset of obesity during childhood or adolescence are at an increased risk of obesity-related, diseases, both during adolescence and later in adult life. African American girls and women are at an increased risk for obesity, and have substantial rates of obesity-related diseases and causes of death. Further, many African American adult women fail to respond to many of the therapeutic approaches used to treat obesity. At present there are no medical therapies proven effective for the correction of severe obesity in children or adolescents. One medication that may have a favorable risk-benefit ratio in pediatric populations is Orlistat (Xenical, Hoffmann LaRoche). Orlistat works by preventing the action of enzymes in the digestive process, interfering with the absorption of approximately 1/3 of the fat eaten in the diet. Xenical appears to be effective for reducing weight and obesity-associated diseases in obese adults. Researchers propose to determine the safety, tolerability, and efficacy of Xenical in 12-17 year old severely obese African American and Caucasian children and adolescents who have one or more obesity-related disease (hypertension, hyperlipidemia, sleep apnea, hepatic steatosis, insulin resistance, impaired glucose tolerance, or Type 2 diabetes).
NCT00108524 ↗	A Low-Carbohydrate, Ketogenic Diet Versus Orlistat for Weight Loss	Completed	US Department of Veterans Affairs	N/A	2004-07-01	This study compares two types of diet interventions: a low carbohydrate ketogenic diet (Atkins) and a low-fat diet combined with a medication (Orlistat).
NCT00108524 ↗	A Low-Carbohydrate, Ketogenic Diet Versus Orlistat for Weight Loss	Completed	VA Office of Research and Development	N/A	2004-07-01	This study compares two types of diet interventions: a low carbohydrate ketogenic diet (Atkins) and a low-fat diet combined with a medication (Orlistat).
NCT00152360 ↗	The Effect of Xenical on Weight and Risk Factors	Completed	University of British Columbia	Phase 4	2005-06-01	The purpose of this study is to determine the effect of using the weight loss medication Xenical (generic name - orlistat) on weight loss and change in heart disease risk factors in patients of the Healthy Heart Program Lipid Clinic at St. Paul's Hospital over a three month period. Xenical works by blocking the body's absorption of dietary fat in the gut, allowing it to pass through to be excreted, therefore reducing the intake of fat and calories. This is a pilot study supported by Hoffmann-La Roche Limited which produces Xenical. The aim is to investigate whether weight loss will also result in reductions in heart disease risk factors that may allow for less of a need for medications controlling lipid levels, hypertension and plasma glucose.
NCT00156897 ↗	Efficacy and Safety of ATL-962 in Obese Diabetics	Completed	Alizyme	Phase 2	2004-12-01	The purpose of this study is to investigate whether ATL-962 induces weight loss in diabetic patients and whether its safety and tolerability profile is superior to that of orlistat in such patients

Clinical Trial Conditions for orlistat

Condition Name

Condition Name for orlistat
Intervention	Trials
Obesity	40
Overweight	8
Weight Loss	4
Overweight or Obesity	4

Condition MeSH

Condition MeSH for orlistat
Intervention	Trials
Obesity	32
Overweight	18
Weight Loss	13
Diabetes Mellitus	10

Clinical Trial Locations for orlistat

Trials by Country

Trials by Country for orlistat
Location	Trials
United States	54
China	27
Sweden	6
Brazil	6
United Kingdom	6

Trials by US State

Trials by US State for orlistat
Location	Trials
Texas	6
North Carolina	5
Ohio	4
New York	4
California	4

Clinical Trial Progress for orlistat

Clinical Trial Phase

Clinical Trial Phase for orlistat
Clinical Trial Phase	Trials
PHASE4	5
PHASE3	1
PHASE2	4

Clinical Trial Status

Clinical Trial Status for orlistat
Clinical Trial Phase	Trials
Completed	38
Recruiting	7
Active, not recruiting	5

Clinical Trial Sponsors for orlistat

Sponsor Name

Sponsor Name for orlistat
Sponsor	Trials
Hoffmann-La Roche	5
GlaxoSmithKline	5
Empros Pharma AB	4

Sponsor Type

Sponsor Type for orlistat
Sponsor	Trials
Other	74
Industry	35
NIH	6

Orlistat Clinical Trials Update, Market Analysis, and US Launch/Exclusivity Projection

Last updated: May 20, 2026

Orlistat is an anti-obesity gastrointestinal lipase inhibitor sold as over-the-counter (OTC) Xenical is prescription; the active ingredient is long off the dominant primary patent lock in most jurisdictions. The remaining market upside is driven by (1) OTC access and (2) line extensions and formulation differentiation (not new “blockbuster” clinical development), with limited late-stage pivotal programs. Competitive pressure is primarily from other weight-loss agents (GLP-1 and GIP/GLP-1 class) and from domestic brands of orlistat-based generics.

What clinical trials are happening for orlistat in 2024–2026, and what outcomes matter?

Orlistat’s modern clinical development is mostly incremental: comparative effectiveness, real-world adherence, tolerability in key populations, and dose/formulation comparisons. Late-stage, label-expansion, or new mechanism-of-action (MOA) trials are rare versus modern incretin therapies, which dominate obesity pipelines.

Are there any new phase 3 or phase 4 trials that could change the label?

No specific public evidence was identified in the provided context that shows an ongoing, company-sponsored phase 3 program for label expansion of orlistat within the 2024–2026 window. The historical trial record for orlistat is largely earlier (body-weight loss, maintenance, and metabolic endpoints) rather than new regulatory-defining late-stage outcomes.

What endpoints do sponsors typically use for orlistat studies?

Across comparative and real-world studies, the endpoints that usually drive clinical and reimbursement value are:

• Change in body weight and weight-loss responder rates
• Percent weight loss from baseline
• Maintenance of weight reduction over 12+ months
• Adverse event burden, especially gastrointestinal (GI) tolerability
• Adherence and discontinuation rates
• Metabolic biomarkers often included as supportive endpoints (lipids, insulin resistance markers)

What patient populations show the most trial activity for orlistat?

Where clinical work persists, it tends to cluster around:

• Adults with overweight/obesity and lifestyle modification failure
• Patients needing adjunctive therapy with calorie restriction
• Comorbid metabolic risk profiles (dyslipidemia, prediabetes), as secondary analyses

What is the Orlistat market size, growth drivers, and where is demand concentrated?

Orlistat is a mature, commoditized obesity pharmacotherapy. Global demand persists due to availability, affordability, and a long history of clinical use, even as prescription obesity growth shifts toward GLP-1/GIP/GLP-1 agents.

Market structure: OTC and prescription segmentation

Orlistat demand divides into:

• OTC orlistat-containing products in markets where the active ingredient is de-regulated for consumer use
• Prescription-strength orlistat where regulatory frameworks keep it as a Rx weight-management medicine

The OTC segment is typically more resilient in volume because it lowers access barriers and reduces prescriber friction.

Growth drivers in a GLP-1-dominant obesity market

Key drivers still sustaining orlistat volume:

• Cost sensitivity and payer limitations for incretin drugs
• Step-therapy and formulary tiers that keep older low-cost options available
• Consumer demand for accessible weight-management products
• Brand-level differentiation via dosing convenience, tablet strength, and GI tolerability positioning

Downside drivers

• Competitive displacement by incretin therapies with higher efficacy
• Generic substitution reducing brand pricing power
• GI adverse events limiting adherence in broader consumer populations

What are the competitive dynamics for orlistat, and how does it compare with GLP-1 obesity drugs?

Orlistat competes primarily in the “cost-access” segment of obesity and in patients for whom incretin therapy is not feasible. Clinical effectiveness is lower than modern injectables, which shifts orlistat positioning to affordability, oral administration, and long-standing safety familiarity.

Competitive comparison summary

Attribute	Orlistat	GLP-1 / GIP-GLP-1 injectables
Administration	Oral, with meals	Weekly injection
Typical efficacy (directional)	Moderate weight loss	Higher average weight loss
Main limiting factor	GI adverse events; adherence	Cost, access, adverse events (class-specific)
Payer stance	Often available on lower tiers	Often requires authorization, prior approval
Differentiation levers	Formulation, adherence support, tolerability claims	Dose, titration, long-term outcomes

When does orlistat lose exclusivity, and what does exclusivity look like across major markets?

Because orlistat is a legacy active ingredient with long-standing approvals, exclusivity has largely expired. Any remaining exclusivity is generally limited to:

• Specific salt form or formulation patents (where still active)
• Method-of-use patents (if any remain granted and enforced in a given jurisdiction)
• Regulatory exclusivities tied to specific product/competitor-specific dossiers (not the active ingredient itself)

Practical implication for market entry

The “exclusivity” relevant to an entrant today is less about blocking the active ingredient and more about avoiding infringement of any still-active, product-specific or method patents in a target country.

What patents protect orlistat, and how many patent families remain enforceable?

Orlistat is an old small molecule. The active ingredient itself is not expected to have dominant, worldwide blockbuster patent coverage remaining. Residual patent enforcement typically comes from secondary IP around:

• Formulations and manufacturing processes
• Specific dosing regimens and method-of-use claims
• Packaging or combination products (if any are protected)

Patent estate reality check

• The number of enforceable families is typically small relative to newer obesity agents.
• The risk for generics is usually concentrated on formulation and method-of-use claims that could be product-specific.

Litigation and enforcement risk

In established generics markets, litigation risk is typically higher only when:

• A branded differentiated formulation still has active IP in that jurisdiction
• A challenger product uses a protected process or formulation design-around that fails on claim scope

What Orange Book status applies to orlistat in the US?

Orlistat is widely available in the US market as generics and OTC products. For a branded Rx product to have meaningful current US exclusivity, it would need active FDA Orange Book listings for relevant patents and exclusivity codes. For orlistat, current market reality indicates most core patents have expired, and multiple ANDA products coexist.

What generic entry risks exist for orlistat, including Paragraph IV?

Given orlistat’s age and widespread generic availability, Paragraph IV challenges historically drive generic entry mainly where listed patents still constrain specific formulations or methods. For today’s entrant, the main legal diligence is a mapping exercise:

• Check whether any active Orange Book patents remain for specific orlistat-labeled strengths/forms.
• Determine whether any method-of-use or formulation patents are listed for the brand product still competing in that segment.
• Assess whether the proposed ANDA label and product composition avoid infringement.

What formulation patents can differentiate orlistat products, and why do they matter commercially?

Even with expired active-ingredient patents, commercial differentiation persists via:

• Tablet composition and disintegration profile
• Coated vs uncoated tablets
• Dosage strength and excipient selection impacting stability and GI tolerability
• Manufacturing process controls that can reduce variability and support bioequivalence consistency

These patents can matter because they can delay generic versions tied to a protected composition, depending on claim scope and enforcement posture.

How do method-of-use claims affect prescribing and labeling?

If any active method-of-use patents exist, they can restrict:

• Labeling language
• Off-label prescribing risk strategy for brand vs generic
• Settlement terms that may include label carve-outs

What FDA regulatory status applies to orlistat, and what approvals remain relevant?

Orlistat is already an established active ingredient with long historical approvals. For any new development to matter regulatorily, it would need:

• A new clinical data package for label expansion
• A new formulation requiring additional CMC work and possibly bridging data
• A combination product strategy that changes regulatory categorization

In a mature active ingredient scenario, most “new” activity is product lifecycle management rather than new clinical breakthroughs.

What is the commercial trajectory for orlistat, and what revenue projection should businesses use?

Market forecast framing for a mature molecule

Orlistat is not positioned for high-growth like next-gen obesity agents. Business projections should assume:

• Low-to-mid single-digit volume growth at best in markets where OTC access expands
• Price compression driven by generic substitution
• Share loss in clinics to GLP-1/GIP/GLP-1 as payers and clinicians migrate

Revenue projection drivers

Volume outcomes depend on:

• OTC penetration and retail distribution strength
• Competitor intensity from other obesity OTC products and prescription incretin drugs via coverage
• Local pricing, reimbursement dynamics, and pharmacy channel contracts

Pricing outcomes depend on:

• Generic brand count and margin pressure
• Any remaining differentiation that supports higher unit price

Key Takeaways

• Orlistat clinical activity is primarily incremental and not dominated by new phase 3 label-changing programs in the 2024–2026 window.
• The market is mature and commoditized; sustained demand is driven by OTC access and cost sensitivity as incretin drugs dominate efficacy-led prescribing.
• Exclusivity is largely expired for the active ingredient; remaining legal risk focuses on any still-active, product-specific formulation or method-of-use patents in specific jurisdictions.
• Commercial upside is constrained by price compression and displacement by GLP-1/GIP/GLP-1 therapies; projections should prioritize OTC-led volume and channel execution rather than expecting novel clinical differentiation to reset adoption curves.

FAQs

1) Is orlistat still recommended for long-term weight management in current clinical practice?
It is used as an adjunct to diet and exercise, with attention to tolerability and adherence; adoption is constrained compared with newer incretin-based regimens.

2) Do orlistat products differ materially in GI tolerability, and does that affect switching?
Yes, excipient selection and formulation can influence GI events, affecting adherence and switching between brands and generics.

3) What is the main regulatory path for a generic orlistat product in the US?
Typically an ANDA with bioequivalence and CMC to an approved reference listed product, unless product-specific patents or label restrictions apply.

4) How does orlistat compare for patients with diabetes or prediabetes?
Evidence base supports metabolic improvements as secondary outcomes, but weight loss magnitude is generally lower than newer obesity drugs.

5) What business levers can still grow an orlistat franchise despite patent expiration?
OTC channel expansion, pack-size strategy, tolerability-focused formulation improvements, and adherence-support marketing in cost-sensitive segments.

References

1. FDA. Orange Book: Approved Drug Products with Therapeutic Equivalence Evaluations. US FDA.
2. ClinicalTrials.gov. Orlistat (search results). U.S. National Library of Medicine.
3. EMA. Public assessment reports and EPARs for orlistat-containing products. European Medicines Agency.