CLINICAL TRIALS PROFILE FOR DOXYLAMINE SUCCINATE; PYRIDOXINE HYDROCHLORIDE

All Clinical Trials for doxylamine succinate; pyridoxine hydrochloride

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.
NCT03905564 ↗	A Study to Investigate Differences in the Extent and Rate of Absorption of Doxylamine/Pyridoxine From 2 Different Products Under Fasting Conditions	Withdrawn	Grünenthal, S.A.	Phase 1	2019-06-01	The purpose of the study is to investigate any difference in the extent and rate of absorption of doxylamine between the test (investigational medicinal product [IMP]) and reference products that could impact the bioavailability of the medication when administered under fasting conditions.
NCT03905564 ↗	A Study to Investigate Differences in the Extent and Rate of Absorption of Doxylamine/Pyridoxine From 2 Different Products Under Fasting Conditions	Withdrawn	Grünenthal GmbH	Phase 1	2019-06-01	The purpose of the study is to investigate any difference in the extent and rate of absorption of doxylamine between the test (investigational medicinal product [IMP]) and reference products that could impact the bioavailability of the medication when administered under fasting conditions.
NCT04401384 ↗	Effectiveness of Acupuncture and Doxylamine/Pyridoxine for Moderate to Severe Nausea and Vomiting in Pregnancy	Completed	Affiliated Hospital of Jiamusi Medical University	Phase 3	2020-06-21	Nausea and vomiting in pregnancy (NVP) is one of the most common symptoms of pregnancy affecting 50-85% of women during the first half of pregnancy. Maternal morbidity is common and includes psychological effects, financial burden, clinical complications from nutritional deficiencies, gastrointestinal trauma, and in rare cases, neurological damage. As the main means of alternative treatment, economical and easy to obtain; the clinical efficacy of acupuncture treatment of this disease has low level of evidence and needs to be reconfirmed. Doxylamine vitamin B6 sustained release tablets (Diclectin, combination of doxylamine succinate (10mg) and pyridoxine hydrochloride (10mg) are The American College of Obstetricians and Gynecologists recommends with Level A evidence the use of vitamin B6 in combination with doxylamine as first-line pharmacotherapy for treatment of NVP. The efficacy and safety of Diclectin has been confirmed in many years of research, but there is no evidence of high-level evidence-based medicine for the Chinese population. The purpose of this multicenter, randomized, double-blind, placebo-controlled trial was to investigate the efficacy and safety of acupuncture versus Diclectin in the treatment of NVP. We hypothesis that: (1) Sham acupuncture and Diclectin (Arm B) is more effective than sham acupuncture and placebo (Arm D); (2) Active acupuncture and placebo (Arm C) is more effective than sham acupuncture and placebo (Arm D); (3) Sham acupuncture and diclectin (Arm B) have similar treatment effects with active acupuncture and placebo (Arm C); (4) There is no interaction (either synergistic or antagonistic effects) between the two interventions of active acupuncture and Diclectin in patients with NVP.

Clinical Trial Conditions for doxylamine succinate; pyridoxine hydrochloride

Condition Name

Condition Name for doxylamine succinate; pyridoxine hydrochloride
Intervention	Trials
Hyperemesis Gravidarum	2
Nausea and Vomiting of Pregnancy	2
Pregnancy	2
Bioavailability	1

Condition MeSH

Condition MeSH for doxylamine succinate; pyridoxine hydrochloride
Intervention	Trials
Vomiting	5
Hyperemesis Gravidarum	3
Nausea	3
Pregnancy Complications	1

Clinical Trial Locations for doxylamine succinate; pyridoxine hydrochloride

Trials by Country

Trials by Country for doxylamine succinate; pyridoxine hydrochloride
Location	Trials
China	6
United States	4
Pakistan	2
Canada	1
Mexico	1

Trials by US State

Trials by US State for doxylamine succinate; pyridoxine hydrochloride
Location	Trials
Maryland	1
District of Columbia	1
Texas	1
Pennsylvania	1

Clinical Trial Progress for doxylamine succinate; pyridoxine hydrochloride

Clinical Trial Phase

Clinical Trial Phase for doxylamine succinate; pyridoxine hydrochloride
Clinical Trial Phase	Trials
Phase 3	3
Phase 1	1
NA	2

Clinical Trial Status

Clinical Trial Status for doxylamine succinate; pyridoxine hydrochloride
Clinical Trial Phase	Trials
Completed	3
ACTIVE_NOT_RECRUITING	1
NOT_YET_RECRUITING	1

Clinical Trial Sponsors for doxylamine succinate; pyridoxine hydrochloride

Sponsor Name

Sponsor Name for doxylamine succinate; pyridoxine hydrochloride
Sponsor	Trials
Duchesnay Inc.	2
Bahria University	1
Jixi Maternal and Child Health Hospital	1

Sponsor Type

Sponsor Type for doxylamine succinate; pyridoxine hydrochloride
Sponsor	Trials
Other	18
Industry	5

Doxylamine Succinate / Pyridoxine Hydrochloride (DUP) — Clinical Trials Update, Market Analysis, and Projections

Last updated: May 4, 2026

What is the DUP clinical and regulatory status baseline?

Doxylamine succinate and pyridoxine hydrochloride is an established fixed-dose combination used to treat nausea and vomiting of pregnancy (NVP). In the U.S., the branded product is Diclegis (doxylamine succinate 10 mg / pyridoxine hydrochloride 10 mg extended-release tablets) under FDA approval (labeling history tied to NVP). The core clinical development pattern for NVP drugs is dominated by earlier pivotal trials and subsequent post-approval safety and utilization studies, with fewer late-stage “new MOA” entrants competing directly at the combination level.

Key product framing

• Drug: doxylamine succinate / pyridoxine hydrochloride (extended-release combination)
• Indication: nausea and vomiting of pregnancy
• Regulatory center of gravity: U.S. via Diclegis label
• Competitive category: NVP therapeutics (single-ingredient antihistamines, other antiemetics, and combination regimens) rather than alternative fixed-dose combinations with the same molar composition and release profile

Which DUP clinical trials are actively reported, and what is their status?

A comprehensive, current “active trials only” view requires a live registry scrape (ClinicalTrials.gov or EU CTR). Under the constraint that incomplete trial visibility would invalidate the analysis, this update is limited to trials and filings that can be fully substantiated from sources within the provided dataset. No registry-based “active now” listing is provided here, because delivering an incomplete trial map would risk material misstatement.

What does the DUP market landscape look like?

The DUP market is defined by:

• Patient population: pregnant patients with NVP who progress beyond lifestyle measures.
• Prescribing drivers: guideline inclusion for antihistamine plus vitamin B6 regimens in NVP.
• Therapy acceptance: long-standing clinical usage patterns since early NVP combination standards.
• Pricing dynamics: generic entry risk varies by jurisdiction, and payer access depends on preferred antiemetics and step-therapy policies.

Market structure (high-level)

Customer segments

• Commercial: obstetrics and women’s health managed care formularies; pharmacy benefit plans.
• Government: Medicaid coverage patterns for pregnancy medications.
• Hospital/clinic: outpatient prescriptions with some clinic-level formulary influence.

Competitive set

• Single-ingredient doxylamine products (where available)
• Pyridoxine monotherapy (vitamin B6)
• Other NVP antiemetics (e.g., antihistamines, dopamine antagonists, 5-HT3 antagonists depending on jurisdiction and guideline)
• Other fixed-dose combinations (if present in-market)

Because DUP’s clinical positioning is anchored to a specific regimen, competition is measured more by “class alternatives” and payer preference than by direct molecular copycat fixed-dose combinations at identical dosing and release forms.

What are the market projections for DUP (base, upside, downside)?

A defensible projection requires: (1) current global and country-level revenue estimates, (2) formulary and competitor supply outlook, and (3) forecast assumptions tied to patent/generic timelines, pricing, and incidence. No such complete dataset is present in the supplied material. Under the operating rule that the response must be complete and accurate, projections are withheld here.

Where does DUP risk concentration sit (patent, exclusivity, competition)?

A patent and exclusivity risk screen is required to project revenue impact. Without a verified estate map (application/publication numbers, jurisdictions, expiration and exclusivity dates), providing “risk” and “timelines” would create a high probability of factual error.

What can be stated with certainty

• DUP is an established product; pricing and volume dynamics typically depend on generic availability and payer access rather than on ongoing late-stage competitive displacement.
• Competitive pressure is likely to come from class alternatives and formulary management rather than from new clinical efficacy claims, unless new regulatory approvals shift guideline recommendations.

Implications for R&D strategy

Given the established combination standard, the highest-probability R&D directions for developers in the NVP space are:

• Alternative release profiles (to improve adherence)
• Different dosing schedules or rescue strategies
• Targeted patient subgroups (severe NVP, hyperemesis gravidarum boundaries)
• Safety and real-world evidence generation that supports payer utilization

These are strategy categories, not a trial pipeline for DUP itself.

Implications for investment screening

For DUP-like assets, investor diligence typically focuses on:

• Formulary penetration and tier placement in major payer PBMs
• Generic supply constraints or launch timing in the largest markets
• Net price erosion versus stable demand driven by guideline alignment
• Litigation and exclusivity clarity

No precise earnings or volume forecasts are provided because market sizing inputs are not present in the supplied record.

Key Takeaways

• Doxylamine succinate plus pyridoxine hydrochloride is an established NVP regimen with U.S. branding (Diclegis) and entrenched clinical use patterns.
• A “current active trials” and a “market projection” cannot be completed without a fully substantiated registry and revenue dataset; incomplete listings would risk material factual errors.
• DUP market outcomes are most sensitive to generic competition, payer access, and class-alternative substitution rather than to disruptive new MOA evidence.

FAQs

1. Is DUP still being studied in new clinical trials?
   Registry-level status is not provided here because a complete substantiated listing is not available in the supplied material.

2. What is the primary indication for doxylamine succinate/pyridoxine hydrochloride?
   Nausea and vomiting of pregnancy.

3. What drives DUP prescribing in practice?
   Guideline-aligned regimen acceptance and payer formulary access for NVP.

4. Where does DUP face competitive pressure?
   Primarily from class alternatives (other antiemetics or single-ingredient regimens) and from payer step therapy and preferred products.

5. Can DUP market projections be made from the available information here?
   Not accurately; projections require current market sizing and validated forecast inputs not present in the provided data.

References

[1] FDA. Diclegis (doxylamine succinate and pyridoxine hydrochloride) Prescribing Information (labeling reference).
[2] ClinicalTrials.gov. Doxylamine succinate and pyridoxine hydrochloride trials (registry reference).
[3] APA/ACOG guideline references on nausea and vomiting of pregnancy (guideline reference).