CLINICAL TRIALS PROFILE FOR ZANTAC 300

505(b)(2) Clinical Trials for ZANTAC 300

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	NCT00443963 ↗	Total Antioxidant Effects of Esomeprazole in Dyspeptic Patients Receiving Non-steroidal Anti-inflammatory Drugs	Withdrawn	AstraZeneca	Phase 4	2006-12-01	The principal investigator hypothesizes that participants receiving NSAID drugs with dyspeptic symptoms have increased production of gastric levels of free radicals. The primary objective of the study is to determine if Esomeprazole Magnesium increases gastric total antioxidant capacity and decreases gastric free radical production in humans. Participants (age 18 years and older) with no history of upper GI bleeding who are receiving non-steroidal anti-inflammatory drugs and then develop dyspepsia will be recruited from our primary care clinic in Washington, DC. All eligible participants will undergo biopsies of antrum and corpus. The participants will be randomized to receive either Zantac OTC or Nexium for 15 days. On day 15, all participants will undergo repeat upper endoscopy to obtain biopsies of antrum and corpus. Tissue samples will then be extracted to determine total antioxidant capacity and lipid peroxide levels (as an indirect marker of free radical production).
OTC	NCT00443963 ↗	Total Antioxidant Effects of Esomeprazole in Dyspeptic Patients Receiving Non-steroidal Anti-inflammatory Drugs	Withdrawn	Medstar Health Research Institute	Phase 4	2006-12-01	The principal investigator hypothesizes that participants receiving NSAID drugs with dyspeptic symptoms have increased production of gastric levels of free radicals. The primary objective of the study is to determine if Esomeprazole Magnesium increases gastric total antioxidant capacity and decreases gastric free radical production in humans. Participants (age 18 years and older) with no history of upper GI bleeding who are receiving non-steroidal anti-inflammatory drugs and then develop dyspepsia will be recruited from our primary care clinic in Washington, DC. All eligible participants will undergo biopsies of antrum and corpus. The participants will be randomized to receive either Zantac OTC or Nexium for 15 days. On day 15, all participants will undergo repeat upper endoscopy to obtain biopsies of antrum and corpus. Tissue samples will then be extracted to determine total antioxidant capacity and lipid peroxide levels (as an indirect marker of free radical production).
OTC	NCT03145012 ↗	Histamine Receptor 2 Antagonists as Enhancers of Anti-Tumour Immunity	Unknown status	Dalhousie University	Phase 4	2018-05-01	The immune response against tumors can be highly effective in preventing tumor development, growth and metastasis under certain circumstances. However, tumor associated immune suppression can profoundly limit the impact of natural tumor immunity and also reduce the effectiveness of tumor immunotherapy strategies. A major component of tumor associated immune suppression is mediated by myeloid cells, especially the monocytic subset of myeloid derived suppressor cells (MDSC). In recent studies that were conducted through a CCSRI Innovation grant, the investigators discovered that oral treatment of mice with the commonly used histamine receptor 2 (H2) antagonists ranitidine or famotidine inhibits both primary breast tumor development and metastasis, in three distinct mouse tumor models and reduces the numbers of monocytic MDSC. These findings have enormous potential to aid in effective cancer immunotherapy and may have immediate implications for cancer patients. The objective of this investigation is to determine whether treatment with the H2 receptor antagonist ranitidine alters immune suppression, through modulation of immune cell populations. The investigators will examine peripheral blood monocyte, neutrophil and NK cell numbers, subsets and activation status from healthy volunteers treated for 6 weeks with daily oral ranitidine. Ranitidine is widely available and used over the counter in Canada. These drugs are widely recognized as safe, well tolerated and have very few side effects. It has been suggested that among the general population, over 10% of those over the age of 65 take such medications on a regular basis for relief against gastrointestinal discomfort. The outcome of pre-clinical studies in mice warrant further investigation into transferability to humans. If the outcome of the current proposal proves to be viable, then these drugs could provide a safe method to reduce tumor associated immunosuppression with broad implications, both for current cancer patients and for those at high risk of developing cancer. Further to this, the outcome of our proposal may provide a new strategy for improving the effectiveness of T-cell mediated immunotherapy.
OTC	NCT03145012 ↗	Histamine Receptor 2 Antagonists as Enhancers of Anti-Tumour Immunity	Unknown status	Nova Scotia Health Authority	Phase 4	2018-05-01	The immune response against tumors can be highly effective in preventing tumor development, growth and metastasis under certain circumstances. However, tumor associated immune suppression can profoundly limit the impact of natural tumor immunity and also reduce the effectiveness of tumor immunotherapy strategies. A major component of tumor associated immune suppression is mediated by myeloid cells, especially the monocytic subset of myeloid derived suppressor cells (MDSC). In recent studies that were conducted through a CCSRI Innovation grant, the investigators discovered that oral treatment of mice with the commonly used histamine receptor 2 (H2) antagonists ranitidine or famotidine inhibits both primary breast tumor development and metastasis, in three distinct mouse tumor models and reduces the numbers of monocytic MDSC. These findings have enormous potential to aid in effective cancer immunotherapy and may have immediate implications for cancer patients. The objective of this investigation is to determine whether treatment with the H2 receptor antagonist ranitidine alters immune suppression, through modulation of immune cell populations. The investigators will examine peripheral blood monocyte, neutrophil and NK cell numbers, subsets and activation status from healthy volunteers treated for 6 weeks with daily oral ranitidine. Ranitidine is widely available and used over the counter in Canada. These drugs are widely recognized as safe, well tolerated and have very few side effects. It has been suggested that among the general population, over 10% of those over the age of 65 take such medications on a regular basis for relief against gastrointestinal discomfort. The outcome of pre-clinical studies in mice warrant further investigation into transferability to humans. If the outcome of the current proposal proves to be viable, then these drugs could provide a safe method to reduce tumor associated immunosuppression with broad implications, both for current cancer patients and for those at high risk of developing cancer. Further to this, the outcome of our proposal may provide a new strategy for improving the effectiveness of T-cell mediated immunotherapy.

All Clinical Trials for ZANTAC 300

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00030992 ↗	BMS 247550 to Treat Kidney Cancer	Completed	National Cancer Institute (NCI)	Phase 2	2002-02-01	This study will examine whether the experimental drug BMS 247550 (Ixabepilone) is an effective treatment for kidney cancer. BMS 247550 belongs to a class of drugs called epothilones that interfere with the ability of cancer cells to divide. In the way they kill cells, they are very similar to a class of compounds known as the taxanes, which include the drug Taxol. Other characteristics of the epothilones, however, enable them to work in cells that are resistant to Taxol. Patients 18 years of age or older with kidney cancer that has not spread to the central nervous system (unless the brain tumor has remained stable for at least six months after surgical or radiation treatment) may be eligible for this study. Pregnant or nursing women may not participate. Candidates are screened with various tests that may include blood and urine tests, electrocardiogram (EKG), and chest x-ray. Computerized tomography (CT) scans or X-rays, and possibly nuclear medicine studies may be done to determine the extent of disease. Participants receive BMS 247550 by a 1-hour infusion into a vein for 5 consecutive days (days 1, 2, 3, 4 and 5) of each 21-day treatment cycle. Patients must stay in the National Institutes of Health (NIH) area near Bethesda, Maryland, for 7 to 8 days during the first treatment cycle and for the 5 days of treatment in subsequent cycles. The total number of cycles will vary among patients, depending on their individual clinical situation. The drug dose may be increased gradually in subsequent cycles in patients who can tolerate such increases. In addition, participants undergo the following tests and procedures: - Periodic physical examinations and frequent blood tests - X-ray and other imaging studies to determine if the tumor is responding to the treatment. - Tumor biopsies to confirm the diagnosis or spread of tumor and to examine the reaction of certain proteins in cancer cells to BMS 247550. Two biopsies will be done. For this procedure, a small piece of tumor tissue is withdrawn through a needle under local anesthetic. Treatment will be stopped in patients whose tumor grows while receiving BMS 247550. Patients whose tumor disappears completely will be followed at NIH periodically for examinations and tests. Patients whose disease does not completely resolve or whose disease recurs may be advised of other appropriate research protocols at NIH or, if none are available, will be returned to the care of their local doctor.
NCT00223691 ↗	Treatment of Orthostatic Hypotension in Autonomic Failure	Completed	Vanderbilt University	Phase 1	2002-03-01	The autonomic nervous system serves multiple regulatory functions in the body, including the regulation of blood pressure and heart rate, gut motility, sweating and sexual function. There are several diseases characterized by abnormal function of the autonomic nervous system. Medications can also alter autonomic function. Impairment of the autonomic nervous system by diseases or drugs may lead to several symptoms, including blood pressure problems (e.g., high blood pressure lying down and low blood pressure on standing), sweating abnormalities, constipation or diarrhea and sexual dysfunction. Because treatment options for these patients are limited. We propose to study patients autonomic failure and low blood pressure upon standing and determine the cause of their disease by history and examination and their response to autonomic testing which have already been standardized in our laboratory. Based on their possible cause, we will tests different medications that may alleviate their symptoms.
NCT00223691 ↗	Treatment of Orthostatic Hypotension in Autonomic Failure	Completed	Vanderbilt University Medical Center	Phase 1	2002-03-01	The autonomic nervous system serves multiple regulatory functions in the body, including the regulation of blood pressure and heart rate, gut motility, sweating and sexual function. There are several diseases characterized by abnormal function of the autonomic nervous system. Medications can also alter autonomic function. Impairment of the autonomic nervous system by diseases or drugs may lead to several symptoms, including blood pressure problems (e.g., high blood pressure lying down and low blood pressure on standing), sweating abnormalities, constipation or diarrhea and sexual dysfunction. Because treatment options for these patients are limited. We propose to study patients autonomic failure and low blood pressure upon standing and determine the cause of their disease by history and examination and their response to autonomic testing which have already been standardized in our laboratory. Based on their possible cause, we will tests different medications that may alleviate their symptoms.
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.

Clinical Trial Conditions for ZANTAC 300

Condition Name

Condition Name for ZANTAC 300
Intervention	Trials
NSAID Associated Gastric Ulcers	2
Healthy	2
Colon Cancer	1
Immune Deficiency	1

Condition MeSH

Condition MeSH for ZANTAC 300
Intervention	Trials
Ulcer	3
Stomach Ulcer	2
Hypotension	2
Vomiting	1

Clinical Trial Locations for ZANTAC 300

Trials by Country

Trials by Country for ZANTAC 300
Location	Trials
United States	12
Pakistan	2
Canada	2
Japan	1
United Kingdom	1

Trials by US State

Trials by US State for ZANTAC 300
Location	Trials
Maryland	3
Texas	2
Wisconsin	1
Utah	1
California	1

Clinical Trial Progress for ZANTAC 300

Clinical Trial Phase

Clinical Trial Phase for ZANTAC 300
Clinical Trial Phase	Trials
Phase 4	5
Phase 3	3
Phase 2	6

Clinical Trial Status

Clinical Trial Status for ZANTAC 300
Clinical Trial Phase	Trials
Completed	13
Withdrawn	4
Terminated	2

Clinical Trial Sponsors for ZANTAC 300

Sponsor Name

Sponsor Name for ZANTAC 300
Sponsor	Trials
National Cancer Institute (NCI)	3
AstraZeneca	3
M.D. Anderson Cancer Center	2

Sponsor Type

Sponsor Type for ZANTAC 300
Sponsor	Trials
Other	18
Industry	7
NIH	4

Last updated: July 28, 2026

Zantac 300 (ranitidine 300 mg) clinical trials update, market analysis, and exclusivity projection

Zantac 300 (ranitidine 300 mg) is no longer marketed in the U.S. and is off standard FDA drug supply pathways following global safety withdrawals tied to NDMA risk. Clinical development has effectively stopped; there is no current, credible late-stage or registration-stage ranitidine program for the 300 mg oral product. Market projections are therefore limited to legacy revenue erosion and any ongoing non-U.S. residual sales, where regulatory status remains jurisdiction-specific.

Why did Zantac 300 (ranitidine) lose market authorization and what happened to clinical programs?

What regulatory action ended U.S. commercialization of ranitidine?

Ranitidine’s U.S. status shifted from routine marketing to an FDA-driven market withdrawal environment after FDA announced requests that manufacturers withdraw all ranitidine products from the market due to endogenous formation of NDMA and uncertainty around acceptable limits.

Key milestones:

• FDA safety communication and market withdrawal request covering all ranitidine products (not specific to 300 mg; applies broadly to “ranitidine” oral products).
• Subsequent enforcement and “withdrawal from the market” dynamics drove commercial discontinuation in the U.S., reducing incentives for further development and registration activity for ranitidine.

What clinical trials existed near the end of ranitidine development?

Once NDMA concerns escalated and withdrawals took effect, ranitidine-focused late-stage clinical efforts lost feasibility because sponsors faced:

• No U.S. path to approval for additional indications or formulations.
• Higher risk of supply-chain and product quality disruption.
• Limited marketability to support trial recruitment and commercialization.

Net effect: no sustained program of new pivotal trials for Zantac 300 has continued into a currently actionable FDA-regulatory track.

What is the current Zantac 300 clinical trials landscape (status, phase, and timelines)?

Is there any active Phase 3 or registration trial for ranitidine 300 mg?

There is no ongoing, widely reported Phase 3 or FDA-registration trial for Zantac 300 (ranitidine 300 mg) that would support an “on-rails” projection of clinical-to-market re-entry in the U.S.

Are there any meaningful investigator-sponsored trials still running?

Residual ranitidine use exists in limited geographies for older prescribing practices, but this does not translate into a structured, sponsor-led, late-stage clinical pipeline comparable to pre-withdrawal years.

How to interpret “clinical trials update” for a withdrawn product

For Zantac 300, the most decision-relevant “clinical trials update” is the post-withdrawal evidence posture:

• NDMA formation risk has been the dominant safety question, and it has governed regulatory outcomes.
• Any new clinical study would be judged against a market authorization baseline that is already removed in the U.S.

How big was Zantac 300 (ranitidine) and what does NDMA-driven withdrawal do to revenue?

U.S. revenue trajectory: legacy sales only

Because ranitidine products were withdrawn at the manufacturer request level in the U.S., U.S. revenue for Zantac 300 moved toward zero for ongoing commercialization. Business impact shifts to:

• Remaining inventory sell-through where allowed prior to full withdrawal.
• Replacement by alternative H2 blockers (e.g., famotidine) and PPIs for ulcer, GERD, dyspepsia indications.

Market share displacement: who took the share?

Loss of ranitidine is typically absorbed by:

• PPIs (e.g., omeprazole, esomeprazole, lansoprazole).
• Other H2 blockers, with famotidine often positioned as a direct H2 alternative.

This replacement pattern is consistent with how prescribers treat acid suppression needs when a specific H2 product becomes unavailable.

What are the best comparables to model Zantac 300 demand drop?

Scenario-based projection framework (withdrawal-adjusted)

For a product with U.S. market withdrawal, the correct projection model is not “growth under market expansion.” It is:

• Legacy inventory horizon
• Switching to substitutes
• Legal and supply-chain residuals outside the U.S.

Substitution dynamics by acid-suppression class

• H2-to-H2 substitution: ranitidine replaced by other H2 blockers where available.
• H2-to-PPI substitution: prescribers and formularies shift to PPIs for GERD and ulcer-risk populations.

When does Zantac 300 lose exclusivity and what patents mattered?

Is there meaningful exclusivity for ranitidine in the current environment?

Ranitidine is an old small molecule with a long history; “exclusivity” for the 300 mg brand in the current U.S. context is not a relevant business constraint because:

• The product is withdrawn.
• Generic competition and patent expiry have long been satisfied historically for ranitidine as a molecule.

What does the “exclusivity” question translate to in 2026?

It becomes a question of:

• Residual market authorization outside the U.S.
• Any ongoing litigation-driven settlement dynamics affecting brand remnants.
• Brand-specific inventory and legal posture, not regulatory exclusivity windows.

What is the Orange Book status of Zantac 300 (ranitidine 300 mg)?

Why Orange Book analysis is limited for Zantac 300

Orange Book status is still useful for understanding historical approvals and listing scope, but the withdrawal changes the commercial reality:

• Even if listings exist historically, withdrawal makes “launch timing” irrelevant for the U.S. market going forward.

Practical business read-through

For Zantac 300:

• Treat Orange Book as a historical record.
• Treat commercial access as governed by current regulatory status and market withdrawal enforcement rather than by listed patents.

Are there any Paragraph IV challenges or biosimilar risks?

Paragraph IV challenges

Paragraph IV filings presuppose an FDA-approved reference listed drug with ongoing marketing and a path to commercial launch. With ranitidine withdrawn, Paragraph IV activity for “Zantac 300” as an active U.S. launch target is not a present risk driver.

Biosimilar risk

Zantac 300 is a small molecule; biosimilar frameworks do not apply.

What formulation and method-of-use IP existed for ranitidine 300 mg, and does it matter now?

IP categories historically relevant to H2 blockers

For legacy oral H2 blocker brands, typical IP categories include:

• Compound and composition of matter patents
• Formulation patents (e.g., release profile, excipient systems)
• Method-of-use patents (indications, dosing regimens)

Does legacy IP create barriers now?

Given withdrawal and long-term molecule maturity, legacy IP is not the primary barrier to current market access. The barrier is regulatory status and product availability.

What is the litigation and settlement landscape affecting Zantac 300?

Why litigation is central for decision-making

For ranitidine, litigation around NDMA allegations has been a major commercial driver, even beyond regulatory authorization. The business consequences include:

• Legal costs and potential settlement payments
• Production stoppage or quality system disruption
• Brand value impairment and insurer exposure

What matters for a licensing or investment thesis

Any prospective thesis centered on Zantac 300 should model:

• Total adjudicated/settlement obligations historically associated with ranitidine NDMA claims
• Ongoing claims tail risk
• Corporate restructuring and asset transfers that affect who carries liabilities

What is the current competitive landscape for Zantac 300 replacements?

Direct alternatives by mechanism

• H2 blockers: famotidine is a common substitute class member.
• PPIs: omeprazole and related agents dominate in many formularies for GERD and ulcer-risk management.

Commercial implications

Formulary dynamics tend to favor:

• Lower-cost generics in PPIs and selected H2s
• Established safety profiles relative to ranitidine’s NDMA issues

Geographic projection: where can ranitidine 300 mg still sell?

U.S. baseline

U.S. sales are effectively ended due to withdrawal.

Non-U.S. residual market

Outside the U.S., ranitidine regulatory status depends on national regulators’ decisions around NDMA and acceptable limits, including:

• Whether continued marketing is allowed
• Whether additional restrictions apply
• Whether certain manufacturers remain authorized

A market projection that claims global normalization would be inconsistent with the dominant U.S. withdrawal precedent, so any forecast must treat non-U.S. commercialization as jurisdiction-fragmented.

What is the “market projection” for Zantac 300 over the next 3–5 years?

Base-case projection (most probable)

• U.S.: near-zero ongoing commercial revenue after remaining legacy depletion.
• Global: flat-to-declining overall, with any pockets of sales limited to jurisdictions where ranitidine remains permitted and with heavy discounting as generics of alternatives compete.

Key drivers that could change the projection

• Further regulator action reducing residual authorizations in additional jurisdictions.
• Increased scrutiny of NDMA formation or revised acceptable limits.
• Ongoing product-liability outcomes that influence supply continuation.

Key Takeaways

• Zantac 300 (ranitidine 300 mg) has no viable U.S. forward commercialization pathway due to FDA-driven withdrawal following NDMA concerns.
• Clinical trials progress for ranitidine effectively stopped; no current late-stage registration-stage pipeline exists for the 300 mg oral product.
• Market projections for the U.S. are effectively zero after legacy sell-through; non-U.S. projections are fragmented by national regulator decisions.
• Patent “exclusivity” and Orange Book timing are not decision-critical for the U.S. market today; regulatory status and product availability dominate.
• Competitive substitution concentrates in PPIs and other H2 blockers, led by widely available generics.

FAQs

1) Is Zantac 300 (ranitidine) still available in the U.S. pharmacy channel?
No, ranitidine products were pulled from the U.S. market environment after FDA safety actions addressing NDMA risk.

2) Are there any active ranitidine 300 mg clinical trials today with FDA relevance?
No ongoing, sponsor-led late-stage or registration-relevant trial program is evident for Zantac 300 tied to a U.S. re-approval pathway.

3) Can generics re-launch Zantac 300 via Paragraph IV in the U.S.?
Paragraph IV is not a practical launch mechanism here because the reference product is withdrawn from the U.S. market context.

4) What NDMA risk regulatory conclusion drove the withdrawal?
FDA focused on NDMA formation concerns, including endogenous formation under certain conditions and uncertainty about acceptable exposure levels.

5) What are the most likely substitutes when Zantac 300 is unavailable?
PPIs and other H2 blockers, with famotidine commonly used as a direct class alternative.

References

1. U.S. Food and Drug Administration (FDA). (2019). FDA requests removal of all ranitidine products (Zantac) from the market. FDA Safety Communication.
2. U.S. Food and Drug Administration (FDA). (2020). NDMA found in ranitidine and continued control actions. FDA communications on ranitidine NDMA risk.