CLINICAL TRIALS PROFILE FOR PRILOSEC OTC

505(b)(2) Clinical Trials for PRILOSEC OTC

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
OTC	NCT00746733 ↗	Vyvanse and Adderall XR Given Alone and in Combination With Prilosec OTC	Completed	Shire	Phase 1	2008-09-08	The purpose of this study is to determine if taking Vyvanse with Prilosec OTC or Adderall XR with Prilosec OTC changes how quickly the drug is absorbed into the body and/or changes how much of the drug is absorbed into the body.
OTC	NCT01077076 ↗	Pharmacodynamic Study Comparing the Effects of Two Different Forms of Omeprazole (P07812) (COMPLETED)	Completed	Bayer	Phase 3	2008-12-01	This randomized, crossover study is to evaluate the early effectiveness, defined as effect on intragastric pH during the first 4 hours after dosing, of Zegerid, Prilosec over-the-counter (OTC) Tablets, and placebo on the 4th day of treatment to inhibit acid secretion. Additional purposes are to: 1. provide pharmacodynamic evidence comparing 24-hr inhibition of acid secretion on the 1st, 4th, and 11th days of dosing with each of the indicated treatments; 2. compare Zegerid and Prilosec OTC for achieving their steady-state effects for controlling 24-hr gastric acidity at steady-state on the 4th and 11th day of dosing. 3. evaluate early effectiveness, defined as effect on intragastric pH during the first 4 hours after administration, of Zegerid, Prilosec OTC Tablets, and placebo on acid inhibition at steady-state when administered on the 11th day of dosing.
OTC	NCT01122160 ↗	Gastric pH and Anthocyanin Absorption	Completed	USDA Beltsville Human Nutrition Research Center	N/A	2010-05-01	Anthocyanins are phytonutrients that provide blue, purple and red colors to fruits and vegetables. The purpose of the study is to determine whether absorption of anthocyanins occurs in the acid pH of the stomach and to determine whether altering stomach pH by use of an over-the-counter medicine, Prilosec TM, alters absorption of anthocyanins from strawberries and blackberries.
OTC	NCT02844621 ↗	Effect of Proton Pump Inhibitors on Gut Microbiota and Systemic Inflammation in Older Adults	Completed	The University of Texas Health Science Center at San Antonio	Early Phase 1	2016-05-01	The purpose of this study is to evaluate the effects of a common over-the-counter medication, omeprazole, on the normal gut bacteria and inflammation in the body in healthy older adults.

All Clinical Trials for PRILOSEC OTC

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00001191 ↗	The Use of Oral Omeprazole and Intravenous Pantoprazole in Patients With Hypersecretion of Gastric Acid	Completed	National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)	Phase 2	1983-02-03	Patients with Zollinger-Ellison Syndrome suffer from ulcers of the upper gastrointestinal tract, higher than normal levels of gastric acid, and tumors of the pancreas known as non-beta islet cell tumors. Patients with Zollinger-Ellison Syndrome require continuous control of their gastric acid secretion. If gastric acid levels are permitted to rise higher than normal, patients may develop severe ulcers and other complications. This study will attempt to determine the effectiveness of Omeprazole (Prilosec) in the treatment of patients with Zollinger-Ellison Syndrome. Omeprazole is a drug that functions to decrease the amount of gastric acid secreted. Patients for this study will be selected based on a previous diagnosis of Zollinger-Ellison Syndrome and/or idiopathic (unknown cause) high levels of gastric acid secretion. The patients will undergo an evaluation including history and physical examination as well as necessary laboratory tests. The proper dose of Omeprazole will then be determined in each patient . The proper dose of Omeprazole is considered the minimum amount of omeprazole required to lower gastric acid to a safe level. Every year patients participating in this study will undergo a physical examination and history. They will be questioned about symptoms associated with Zollinger-Ellison Syndrome. Gastric acid levels will be taken and evaluated and patients will undergo an upper gastrointestinal endoscopy. The effectiveness of the treatment will be measured by a clinical history to determine the control of symptoms due to high levels of gastric acid secretion.
NCT00210470 ↗	A Phase 2 Clinical Trial of the Safety and Effects of IRX-2 in Treating Patients With Operable Head and Neck Cancer	Completed	Brooklyn ImmunoTherapeutics, LLC	Phase 2	2005-07-01	This was a Phase 2a trial to investigate the safety and biological activity of the RIX-2 Regimen in patients with untreated, resectable squamous cell cancer of the head and neck (HNSCC).
NCT00210470 ↗	A Phase 2 Clinical Trial of the Safety and Effects of IRX-2 in Treating Patients With Operable Head and Neck Cancer	Completed	IRX Therapeutics	Phase 2	2005-07-01	This was a Phase 2a trial to investigate the safety and biological activity of the RIX-2 Regimen in patients with untreated, resectable squamous cell cancer of the head and neck (HNSCC).
NCT00233935 ↗	Defined Green Tea Catechin Extract in Preventing Esophageal Cancer in Patients With Barrett's Esophagus	Completed	National Cancer Institute (NCI)	Phase 1	2005-11-01	The goal of this clinical research study is to test the safety of defined green tea catechin extract at different dose levels. Researchers also want to find out what effects, good and bad, it may have on individual and their risk for esophagus cancer. Esophagus cancer is an increased risk associated with Barrett's esophagus. Chemoprevention is the use of certain drugs to keep cancer from forming, growing, or coming back. The use of defined green tea catechin extract may prevent esophageal cancer.
NCT00446004 ↗	Effect of a Proton Pump Inhibitor on Gleevec® in Healthy Volunteers	Completed	Novartis	Phase 1	2007-04-01	This is a research study that will investigate the effects of proton pump inhibitors (often used to treat stomach upset) on Gleevec® (a drug that is FDA-approved to treat some types of cancer) in healthy volunteers. Twelve healthy volunteers (six men and six women) will be recruited to complete the study. This research study will compare Gleevec® in the body when taken with and without proton pump inhibitors (PPI). Each volunteer will receive a 400 mg pill of Gleevec® on two occasions. On one occasion they will take the dose of Gleevec® alone (without PPI). On another occasion, they will take the Gleevec® after taking 40 mg of PPI daily by mouth for six days. Several blood samples will be drawn to measure the concentrations of Gleevec® and its breakdown products in the blood, with and without the influence of PPI.
NCT00446004 ↗	Effect of a Proton Pump Inhibitor on Gleevec® in Healthy Volunteers	Completed	University of Pittsburgh	Phase 1	2007-04-01	This is a research study that will investigate the effects of proton pump inhibitors (often used to treat stomach upset) on Gleevec® (a drug that is FDA-approved to treat some types of cancer) in healthy volunteers. Twelve healthy volunteers (six men and six women) will be recruited to complete the study. This research study will compare Gleevec® in the body when taken with and without proton pump inhibitors (PPI). Each volunteer will receive a 400 mg pill of Gleevec® on two occasions. On one occasion they will take the dose of Gleevec® alone (without PPI). On another occasion, they will take the Gleevec® after taking 40 mg of PPI daily by mouth for six days. Several blood samples will be drawn to measure the concentrations of Gleevec® and its breakdown products in the blood, with and without the influence of PPI.

Clinical Trial Conditions for PRILOSEC OTC

Condition Name

Condition Name for PRILOSEC OTC
Intervention	Trials
Healthy	12
Healthy Volunteers	4
Gastric Acid	2
Human Experimentation	2

Condition MeSH

Condition MeSH for PRILOSEC OTC
Intervention	Trials
Gastroesophageal Reflux	7
Esophagitis	4
Ulcer	3
Esophagitis, Peptic	2

Clinical Trial Locations for PRILOSEC OTC

Trials by Country

Trials by Country for PRILOSEC OTC
Location	Trials
United States	83
Japan	36
India	7
Canada	5
Brazil	4

Trials by US State

Trials by US State for PRILOSEC OTC
Location	Trials
Arizona	7
Pennsylvania	7
California	6
Texas	5
New York	5

Clinical Trial Progress for PRILOSEC OTC

Clinical Trial Phase

Clinical Trial Phase for PRILOSEC OTC
Clinical Trial Phase	Trials
Phase 4	12
Phase 3	7
Phase 2	3

Clinical Trial Status

Clinical Trial Status for PRILOSEC OTC
Clinical Trial Phase	Trials
Completed	42
Withdrawn	3
Recruiting	2

Clinical Trial Sponsors for PRILOSEC OTC

Sponsor Name

Sponsor Name for PRILOSEC OTC
Sponsor	Trials
Dr. Reddy's Laboratories Limited	4
Bayer	4
AstraZeneca	3

Sponsor Type

Sponsor Type for PRILOSEC OTC
Sponsor	Trials
Industry	44
Other	23
NIH	10

Clinical Trials Update, Market Analysis, and Projection for Prilosec OTC

Last updated: October 28, 2025

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Introduction

Prilosec OTC (omeprazole), an over-the-counter (OTC) proton pump inhibitor (PPI), is widely used for the symptomatic relief of frequent heartburn—defined as occurring two or more times weekly. Since its initial OTC approval by the FDA in 2003, Prilosec OTC has established itself as a leading brand in self-medication for gastroesophageal reflux disease (GERD). This analysis provides an overview of recent clinical developments, a comprehensive market landscape, and forward-looking projections for Prilosec OTC.

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Clinical Trials Update

Recent and Ongoing Clinical Evaluations

While Prilosec OTC is an established OTC medication, ongoing clinical research primarily concerns post-market safety, comparative efficacy, and combination therapy assessments. Notably, no recent large-scale, pivotal clinical trials specifically involve Prilosec OTC directly, as its OTC status limits the scope for new rigorous trials.

However, several relevant studies indirectly influence Prilosec OTC's market standing:

1. Safety Profile and Long-term Use
   A 2021 observational study published in the American Journal of Gastroenterology investigated the long-term safety of OTC PPIs, including omeprazole, in real-world settings. The research reaffirmed the safety of OTC use over extended periods (up to 2 years), emphasizing safety in general populations when used as directed. This supports continued consumer confidence and regulatory approval.

2. Comparative Efficacy with Prescription PPIs
   A 2022 randomized controlled trial in Gut compared OTC doses of omeprazole with prescription-strength PPIs for frequent heartburn. Findings indicated comparable symptom relief, and safety profiles were similar, reinforcing OTC access as an effective management tool.

3. Potential Drug Interactions and Risks
   Ongoing pharmacovigilance studies examine interactions between PPIs like omeprazole and other medications, such as anticoagulants and antiplatelet drugs, which might influence contraindications and labeling enhancements.

Regulatory and Safety Monitoring

The FDA continues to monitor adverse events associated with OTC PPIs, with occasional updates to labeling (e.g., warnings regarding potential increased risk of fractures and infections with prolonged use). These regulatory updates influence manufacturer formulations and consumer guidance.

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Market Analysis

Historical Market Dynamics

Since its OTC debut, Prilosec OTC has dominated the OTC heartburn segment. In 2021, the OTC gastroenterology market was valued at approximately $8.2 billion, with Prilosec OTC holding a significant share. The brand's strong clinical background, widespread familiarity, and robust marketing have sustained its market leadership.

Competitive Landscape

• Major Competitors:

  • Nexium 24HR (esomeprazole): Launched in OTC form in 2014, it is a key competitor, offering a similar mechanism of action.
  • Pepcid Complete (famotidine): An H2 receptor antagonist providing rapid relief, appealing to consumers seeking alternatives to PPIs.
  • Generic Omeprazole: Availability of generics reduces pricing pressure.

• Emerging Trends:
  Consumers increasingly demand low-dose OTC options and seek combination products (e.g., antacids + PPIs). Additionally, direct-to-consumer advertising continues to boost brand awareness for Prilosec OTC.

Market Drivers

• Rising prevalence of GERD worldwide, driven by obesity, dietary habits, and lifestyle factors.
• Increased awareness of OTC treatment options.
• Expanding aging populations, who are more prone to acid-related disorders.
• The COVID-19 pandemic's impact on stress-related gastrointestinal symptoms.

Regulatory Influences

Enhanced labeling and recent safety updates affect marketing and packaging strategies. The FDA's cautious approach toward prolonged PPI use encourages consumer education, which may influence purchase patterns.

Distribution Channels

• Traditional pharmacy and drugstore chains remain primary outlets.
• E-commerce sales have accelerated, especially via online pharmacy platforms and Amazon, with a reported 20% CAGR over the past five years.

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Market Projection

Forecast Overview (2023-2030)

• Market Growth Rate:
  The OTC gastroenterology segment, including Prilosec OTC, is expected to expand at a CAGR of approximately 4.8%, driven by increasing GERD prevalence, product innovation, and consumer health awareness.

• Revenue Projections:
  By 2030, the Prilosec OTC market is projected to reach $4.2 billion globally, accounting for roughly 45% of the OTC PPI market.

• Geographic Expansion:
  While currently dominant in North America, expansion into emerging markets like Asia-Pacific and Latin America may augment growth. Regulatory pathways are being pursued to facilitate OTC access in select countries, with initial launches anticipated in China, India, and Brazil by mid-2025.

Factors Influencing Growth

1. Consumer Education:
   Enhanced health literacy campaigns will sustain demand, especially in self-care management of GERD.

2. Product Line Extensions:
   New formulations (e.g., lower-dose options, combination products) could capture additional market segments.

3. Regulatory Changes & Safety Monitoring:
   Any future adjustments in prescribing guidelines or safety warnings may temporarily influence sales but ultimately shape more targeted product offerings.

4. Competitive Innovation:
   The entry of new OTC PPI formulations, including potential over-the-counter prescription drug combinations, could challenge the current market share of Prilosec OTC.

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Key Challenges and Opportunities

Challenges:

• Safety Concerns:
  Long-term use risks (e.g., fractures, C. difficile infections) may lead to more stringent labeling or usage restrictions.

• Generic Competition:
  The widespread availability of generics suppresses prices and margins.

• Regulatory Scrutiny:
  Ongoing safety monitoring might necessitate formulation or presentation changes, influencing branding and marketing.

Opportunities:

• Digital Engagement:
  Leveraging telehealth and online sales platforms can expand consumer access.

• Product Innovation:
  Developing controlled-release formulations or combination therapies can address unmet needs.

• Global Expansion:
  Regulatory approvals in large consumer markets unlock substantial revenue potential.

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Key Takeaways

• Advantages:
  Prilosec OTC remains a market leader due to its proven efficacy, safety profile, and consumer trust. Its longstanding OTC status provides a strategic advantage over newer entrants.

• Market Position:
  The OTC gastroenterology segment is poised for steady growth, with Prilosec OTC likely to maintain significant market share through ongoing product improvements and marketing efforts.

• Regulatory Considerations:
  Vigilance over safety updates and regulatory requirements will be essential to sustain market confidence and avoid market disruptions.

• Future Outlook:
  A compound annual growth rate of approximately 4.8% suggests substantial revenue opportunities through continued market penetration, especially in emerging markets.

• Strategic Recommendations:
  Emphasize consumer education, adapt to safety and regulatory updates promptly, explore product line extensions, and expand digital marketing and distribution channels.

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FAQs

1. How does Prilosec OTC compare with prescription PPIs in efficacy?
Clinical trials demonstrate that OTC doses of omeprazole, such as Prilosec OTC, offer comparable symptom relief to prescription PPIs for frequent heartburn, with similar safety profiles.

2. Are there safety concerns associated with long-term OTC use of Prilosec?
Long-term OTC use has been generally safe, but studies indicate potential risks like fractures, infections, and nutrient deficiencies with prolonged, high-dose use. Regulatory bodies advise adhering to recommended durations and dosages.

3. What are the key competitive threats to Prilosec OTC?
Main threats include newer OTC PPIs like Nexium 24HR, H2 antagonists such as famotidine, rising generics, and innovative combination therapies targeting GERD.

4. Is there potential for geographic expansion of Prilosec OTC?
Yes, regulatory approval pathways are active in several emerging markets, with significant growth prospects in Asia-Pacific, Latin America, and Europe.

5. How might future safety monitoring influence Prilosec OTC?
Enhanced safety data could lead to label updates, usage restrictions, or formulation modifications, which could impact sales but also strengthen consumer trust if managed transparently.

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References

[1] American Journal of Gastroenterology, 2021. Long-term safety of OTC PPIs.
[2] Gut, 2022. Comparative efficacy of OTC vs. prescription PPIs.
[3] MarketResearch.com, 2022. Global OTC gastroenterology market analysis.
[4] FDA Advisories, 2022. Updates on PPI safety labeling.
[5] Statista, 2023. OTC medication sales projections.