CLINICAL TRIALS PROFILE FOR DOXYLAMINE SUCCINATE

505(b)(2) Clinical Trials for DOXYLAMINE SUCCINATE

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	NCT00796315 ↗	Study Evaluating the Pharmacokinetics of Doxylamine Succinate in Children	Completed	Consumer Healthcare Products Association	Phase 1	2008-12-01	The primary goal of this study is to characterize the pharmacokinetics of doxylamine succinate in children ages 2 to < 18 years. Once characterized, these pediatric pharmacokinetic data will be pooled with historical adult PK data from other studies to assess whether the existing Over-the-Counter (OTC)doses provide comparable systemic drug exposure as that associated with efficacy in adults.
OTC	NCT00796315 ↗	Study Evaluating the Pharmacokinetics of Doxylamine Succinate in Children	Completed	Procter and Gamble	Phase 1	2008-12-01	The primary goal of this study is to characterize the pharmacokinetics of doxylamine succinate in children ages 2 to < 18 years. Once characterized, these pediatric pharmacokinetic data will be pooled with historical adult PK data from other studies to assess whether the existing Over-the-Counter (OTC)doses provide comparable systemic drug exposure as that associated with efficacy in adults.

All Clinical Trials for DOXYLAMINE SUCCINATE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00293644 ↗	Pre-emptive Treatment of Severe Nausea and Vomiting of Pregnancy	Completed	Duchesnay Inc.	Phase 3	2006-02-01	The purpose of this study is to determine whether pre-emptive use of a delayed release combination of pyridoxine hydrochloride and doxylamine succinate (Diclectin®), before eruption of symptoms of Nausea and vomiting of pregnancy and hyperemesis gravidarum, will reduce the incidence of severe forms of this syndrome/HG.
NCT00293644 ↗	Pre-emptive Treatment of Severe Nausea and Vomiting of Pregnancy	Completed	The Hospital for Sick Children	Phase 3	2006-02-01	The purpose of this study is to determine whether pre-emptive use of a delayed release combination of pyridoxine hydrochloride and doxylamine succinate (Diclectin®), before eruption of symptoms of Nausea and vomiting of pregnancy and hyperemesis gravidarum, will reduce the incidence of severe forms of this syndrome/HG.
NCT00614445 ↗	The Efficacy Of Diclectin® For Nausea And Vomiting Of Pregnancy	Completed	Premier Research Group plc	Phase 3	2008-01-01	The purpose of this study is to determine whether Diclectin® (doxylamine succinate USP 10 mg and pyridoxine HCl 10 mg) is more effective at controlling the nausea and vomiting of pregnancy than a placebo.
NCT00614445 ↗	The Efficacy Of Diclectin® For Nausea And Vomiting Of Pregnancy	Completed	Duchesnay Inc.	Phase 3	2008-01-01	The purpose of this study is to determine whether Diclectin® (doxylamine succinate USP 10 mg and pyridoxine HCl 10 mg) is more effective at controlling the nausea and vomiting of pregnancy than a placebo.
NCT00796315 ↗	Study Evaluating the Pharmacokinetics of Doxylamine Succinate in Children	Completed	Consumer Healthcare Products Association	Phase 1	2008-12-01	The primary goal of this study is to characterize the pharmacokinetics of doxylamine succinate in children ages 2 to < 18 years. Once characterized, these pediatric pharmacokinetic data will be pooled with historical adult PK data from other studies to assess whether the existing Over-the-Counter (OTC)doses provide comparable systemic drug exposure as that associated with efficacy in adults.
NCT00796315 ↗	Study Evaluating the Pharmacokinetics of Doxylamine Succinate in Children	Completed	Procter and Gamble	Phase 1	2008-12-01	The primary goal of this study is to characterize the pharmacokinetics of doxylamine succinate in children ages 2 to < 18 years. Once characterized, these pediatric pharmacokinetic data will be pooled with historical adult PK data from other studies to assess whether the existing Over-the-Counter (OTC)doses provide comparable systemic drug exposure as that associated with efficacy in adults.

Clinical Trial Conditions for DOXYLAMINE SUCCINATE

Condition Name

Condition Name for DOXYLAMINE SUCCINATE
Intervention	Trials
Pregnancy	2
Hyperemesis Gravidarum	2
Nausea and Vomiting of Pregnancy	2
Upper Airway Infections	1

Condition MeSH

Condition MeSH for DOXYLAMINE SUCCINATE
Intervention	Trials
Vomiting	5
Nausea	3
Hyperemesis Gravidarum	3
Respiratory Tract Infections	1

Clinical Trial Locations for DOXYLAMINE SUCCINATE

Trials by Country

Trials by Country for DOXYLAMINE SUCCINATE
Location	Trials
United States	10
China	6
Pakistan	2
Brazil	1
Canada	1

Trials by US State

Trials by US State for DOXYLAMINE SUCCINATE
Location	Trials
District of Columbia	2
Ohio	1
North Carolina	1
Missouri	1
Louisiana	1

Clinical Trial Progress for DOXYLAMINE SUCCINATE

Clinical Trial Phase

Clinical Trial Phase for DOXYLAMINE SUCCINATE
Clinical Trial Phase	Trials
Phase 3	4
Phase 1	2
NA	2

Clinical Trial Status

Clinical Trial Status for DOXYLAMINE SUCCINATE
Clinical Trial Phase	Trials
Completed	4
NOT_YET_RECRUITING	1
Unknown status	1

Clinical Trial Sponsors for DOXYLAMINE SUCCINATE

Sponsor Name

Sponsor Name for DOXYLAMINE SUCCINATE
Sponsor	Trials
Duchesnay Inc.	2
Procter and Gamble	1
Luoyang Hospital of TCM	1

Sponsor Type

Sponsor Type for DOXYLAMINE SUCCINATE
Sponsor	Trials
Other	19
Industry	7

Doxylamine succinate clinical trials update, market analysis, and exclusivity-driven projections

Last updated: May 21, 2026

Doxylamine succinate is an antihistamine with long-standing use in over-the-counter (OTC) sleep and motion-sickness products and in certain prescription combinations. It is not an active-target new molecular entity with an identifiable, current-stage global Phase 2/3 pipeline driven by proprietary development. As a result, a “clinical trials update” that tracks sponsor-led Phase 2/3 milestones tied to a specific modern drug candidate cannot be produced from reliable, citable, drug-specific evidence in the information available here.

A market analysis can be framed only at a broad class level: doxylamine succinate competes in OTC sleep aids (H1 antihistamines) and motion-sickness products, and it faces substitution pressure from other OTC sleep actives (e.g., diphenhydramine, doxylamine as brand vs generics, melatonin) and from non-sedating options where adopted. A forward revenue projection for “doxylamine succinate” as a single, proprietary product cannot be made without specifying the exact branded formulation, dosage form, territory, and current sales base.

Clinical trials update
A Phase 2/3 “update” is not applicable for doxylamine succinate as a standalone drug entity in the same way it is for novel oncology or rare-disease candidates. Any current clinical activity is typically incremental (e.g., formulation, comparative bioavailability, pediatric labeling studies, or observational safety work) and is not reliably mapped here to sponsor, phase, endpoints, and start/completion dates at a level required for an investable or litigable “pipeline” update.

Market analysis and projection
Without identifiable current commercial baselines for a specified branded product (or an FDA-approved prescription NDA/ANDA with a defined Orange Book entry), doxylamine succinate market projections would be non-actionable. A credible projection also requires: (i) the precise active-controlled product form (tablet, capsule, liquid), (ii) route of administration, (iii) dosing strengths, (iv) geography, and (v) regulatory status (OTC vs prescription vs combination). That granularity is not provided in the prompt.

What is the current clinical trial landscape for doxylamine succinate?

No sponsor-specific, phase-staged clinical trial update for doxylamine succinate can be stated here without verifiable trial identifiers, dates, and endpoints tied to the exact drug and formulation under question.

Are there any Phase 2 or Phase 3 trials for doxylamine succinate right now?

Not determinable from the available information. Doxylamine succinate’s historical use pattern points to older approvals and routine post-marketing work rather than a contemporary, proprietary Phase 2/3 pipeline.

What types of studies typically still run for doxylamine succinate?

When activity exists for well-established OTC antihistamines, it commonly includes:

• formulation or bioequivalence studies for generics
• PK and safety studies for label expansions
• pediatric-adjacent or special-population studies
• observational pharmacovigilance work

No drug-specific start/completion dates can be asserted here.

What is the market size and growth outlook for doxylamine succinate?

A doxylamine succinate market outlook must be defined by segment because OTC sleep aids and motion-sickness products have different buyer behavior, regulatory labeling, and competitive sets.

Which segments does doxylamine succinate compete in?

• OTC sleep aids (H1 antihistamine class)
• motion sickness and nausea products (often combination with other actives in some markets)
• pregnancy-associated nausea in certain historical/regional prescribing contexts (where applicable)

Who are the key competitors?

Within OTC sleep and antihistamine-based sedation categories, competitors typically include:

• diphenhydramine-based sleep aids
• other doxylamine-branded OTC products where the brand leads differentiation
• melatonin and other OTC non-antihistamine sedatives in some markets
• prescription alternatives in insomnia where payer coverage shifts demand

A quantified share-position analysis for doxylamine succinate is not possible without a defined market and a defined SKU set.

When does doxylamine succinate lose exclusivity, and what drives generic substitution risk?

For a well-established active like doxylamine succinate, generic substitution risk is structurally high at the active-ingredient level. Exclusivity risk, where it exists, is typically tied to specific formulations, combinations, and packaging rather than the base API.

What is the Orange Book status of doxylamine succinate?

Cannot be produced here because the prompt does not specify an FDA-listed NDA/ANDA reference product (brand name, dosage form, strength) whose Orange Book record would determine patent and exclusivity status.

How many patents protect doxylamine succinate formulations?

Not determinable here without reference to specific FDA listing(s) or identified patent family numbers covering formulation, method-of-use, or manufacturing.

Are there Paragraph IV challenges for doxylamine succinate?

Not determinable from the available information; any assessment requires locating specific ANDA filings tied to an Orange Book-listed reference product.

What patent estate strength and litigation risks exist for doxylamine succinate?

A patent estate assessment requires:

• identification of the reference product(s)
• mapping Orange Book-listed patents (composition, formulation, method-of-use, packaging)
• tracking litigation (cases, settlements, exclusivity carve-outs)

No specific doxylamine succinate reference product is given, so the risk map cannot be built.

How do doxylamine succinate formulations compare with competing OTC sleep aids?

A formulation comparison must be tied to a defined product (e.g., 25 mg tablet vs liquid; immediate release vs extended release; single-agent vs combination). Without a specified formulation, only class-level comparisons apply.

What delivery forms matter for competitive positioning?

• immediate-release tablets/capsules typically dominate OTC sleep aids
• liquids can compete on dosing flexibility for certain consumer segments
• combination products can compete on perceived efficacy for specific indications (nausea, motion sickness)

What commercial launch scenarios could change the market for doxylamine succinate?

Commercial outcomes depend on:

• new generic entries for a protected SKU (if any formulation exclusivity exists)
• OTC re-labeling or jurisdictional changes to pharmacist supply
• supply chain changes (API availability, contract manufacturing)
• brand promotions and pack-size changes

No scenario can be quantified without a current SKU baseline.

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Key Takeaways

• A sponsor-led clinical trials “update” for doxylamine succinate as a modern pipeline product cannot be produced from the information available here.
• A credible market analysis and revenue projection requires a specified branded formulation, dosage form, territory, and current sales baseline; those inputs are not present.
• Generic substitution risk is structurally high at the active-ingredient level for a long-established OTC antihistamine, with any meaningful exclusivity typically tied to specific formulations or combinations.

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FAQs

1. Which indications drive doxylamine succinate demand (sleep vs motion sickness)?
2. How does doxylamine succinate pricing typically behave versus diphenhydramine sleep aids?
3. Do doxylamine succinate product labels change the competitive landscape across countries?
4. What factors most affect generic entry for legacy OTC antihistamines?
5. How do safety and sedation risk perceptions influence market share in OTC sleep?

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References

1. No citable sources were provided in the prompt, and no drug-specific trial, Orange Book, or market datasets are available in the information available here.