List of Excipients in Branded Drug DICLEGIS

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Duchesnay USA Inc	DICLEGIS	doxylamine succinate and pyridoxine hydrochloride	55494-100	ALCOHOL
Duchesnay USA Inc	DICLEGIS	doxylamine succinate and pyridoxine hydrochloride	55494-100	AMMONIA
Duchesnay USA Inc	DICLEGIS	doxylamine succinate and pyridoxine hydrochloride	55494-100	BUTYL ALCOHOL
Duchesnay USA Inc	DICLEGIS	doxylamine succinate and pyridoxine hydrochloride	55494-100	CARNAUBA WAX

DICLEGIS Excipient Strategy and Commercial Opportunities

Last updated: August 14, 2026

DICLEGIS is a delayed-release oral combination of doxylamine succinate 10 mg and pyridoxine hydrochloride 10 mg for nausea and vomiting of pregnancy. Its commercial value depends less on novel active ingredients than on controlled release, pregnancy-oriented safety, tablet burden, manufacturability, and regulatory protection around the formulation and dosing regimen.

The strongest excipient opportunities are modified-release technology, low-risk excipient substitution, color and coating redesign, improved swallowability, and cost reduction without changing the release profile. The principal competitive pathway is an ANDA or, for materially different formulations, a 505(b)(2) application.

What is DICLEGIS and how does its formulation work?

DICLEGIS is a delayed-release tablet containing equal amounts of doxylamine succinate and pyridoxine hydrochloride. The labeled regimen begins with two tablets at bedtime and may increase to four tablets daily, divided between bedtime, morning, and afternoon doses. The product is taken on an empty stomach because food can delay absorption and affect exposure characteristics. (U.S. Food and Drug Administration, 2024a)

Attribute	DICLEGIS profile
Active ingredients	Doxylamine succinate and pyridoxine hydrochloride
Strength per tablet	10 mg/10 mg
Dosage form	Delayed-release tablet
Indication	Nausea and vomiting of pregnancy
Administration	Oral; taken on an empty stomach
Maximum labeled dose	Four tablets daily
U.S. application	NDA 021876
Sponsor	Duchesnay USA Inc.
Initial U.S. approval	2013
Primary formulation issue	Reproducible delayed release for two active ingredients
Relevant competitor	BONJESTA, 20 mg/20 mg extended-release tablets

DICLEGIS is the U.S. commercial successor to the doxylamine/pyridoxine combination historically marketed as Bendectin. The active ingredients are established compounds. The product differentiation is primarily pharmaceutical rather than pharmacological.

What excipients are used in DICLEGIS?

The U.S. prescribing information identifies the following inactive ingredients:

Formulation function	DICLEGIS excipients
Tablet core	Microcrystalline cellulose
Tablet core	Magnesium trisilicate
Tablet core	Croscarmellose sodium
Lubricant	Magnesium stearate
Film coating	Hypromellose
Film coating	Titanium dioxide
Film coating	Talc
Plasticizer or coating aid	Polyethylene glycol
Colorants	FD&C Yellow No. 6 and D&C Yellow No. 10

The label does not publicly disclose the quantitative percentage of each excipient or the detailed manufacturing process. The functional design appears to use a conventional compressed core with a coating or matrix arrangement intended to delay drug release. (U.S. Food and Drug Administration, 2024a)

The excipient system has four commercial requirements:

1. Maintain delayed release in the presence of gastrointestinal pH changes.
2. Preserve dose uniformity for low-dose doxylamine and pyridoxine.
3. Support adequate mechanical strength during packaging and transport.
4. Avoid excipient changes that create new safety, dissolution, or bioequivalence risk in pregnancy.

Which excipients create the largest commercial opportunities?

Modified-release polymers

Hypromellose is the most obvious platform for formulation optimization. Polymer grade, viscosity, particle size, substitution level, and coating weight can change hydration, erosion, and drug release. A competitor could use a different hypromellose grade or another accepted release-controlling polymer, but it would need to demonstrate equivalent dissolution under relevant pH and agitation conditions.

Potential alternatives include:

• Hypromellose of different viscosity grades
• Polyvinyl acetate-based matrix systems
• Methacrylate copolymers
• Ethylcellulose coatings
• Polyethylene oxide matrices
• Multiparticulate systems with functional coatings

A polymer substitution is commercially attractive only if it produces a meaningful manufacturing or supply-chain advantage. The regulatory burden increases if the substitution changes the release mechanism or creates a new pharmacokinetic profile.

Disintegrants

Croscarmellose sodium supports tablet breakup after the delayed-release barrier is overcome. Sodium starch glycolate and crospovidone are possible alternatives, but each can change swelling behavior, compression force, friability, and dissolution.

A disintegrant optimization program could reduce tablet hardness variability and improve dissolution consistency. The main risk is that excessive swelling can rupture a coating or create an early-release phase.

Fillers and compression aids

Microcrystalline cellulose is widely available and commercially practical. Direct-compression grades with different particle-size distributions may improve:

• Content uniformity
• Tablet tensile strength
• Compression throughput
• Weight control
• Tablet size reduction

Mannitol, lactose, dibasic calcium phosphate, and silicified microcrystalline cellulose are possible substitutes. Lactose may raise compatibility or sensitivity concerns in selected manufacturing environments, while mannitol can improve mouthfeel but may increase cost and alter compaction behavior.

Lubricants and glidants

Magnesium stearate is a conventional lubricant, but over-lubrication can reduce tablet strength and impair wetting. Alternatives such as sodium stearyl fumarate may support faster blending or reduce hydrophobicity. Colloidal silicon dioxide can improve flow but may change blend segregation and content uniformity.

For DICLEGIS, lubricant optimization is more likely to create a manufacturing-cost opportunity than a clinically visible product benefit.

Film-coating systems

The coating is a practical area for differentiation. A reformulated product could pursue:

• Lower coating weight
• Water-based coating systems
• Reduced pigment load
• Improved color consistency
• Fewer coating defects
• Lower solvent or energy consumption
• A differentiated tablet appearance

Color changes can have regulatory and commercial consequences. The pregnancy indication makes a conservative approach preferable because unnecessary excipient or colorant changes can create avoidable label and perception issues.

What formulations are protected by DICLEGIS-related intellectual property?

DICLEGIS protection can involve several layers:

Protection layer	Commercial relevance
Delayed-release combination formulation	May limit direct formulation copying
Doxylamine/pyridoxine dosage regimen	May support method-of-use protection
Tablet composition and release profile	May create formulation patent barriers
Manufacturing process	May protect coating, granulation, or compression steps
Trade secrets	May cover quantitative excipient levels and process controls
Trademark	DICLEGIS branding and pregnancy-focused market recognition

The key distinction is between a patent that claims the active ingredients broadly and one that claims a specific delayed-release architecture, dose schedule, or release profile. Because doxylamine and pyridoxine are old active ingredients, the economically important intellectual property is more likely to reside in formulation, dosing, and method-of-use claims than in composition-of-matter claims.

Patent expiration and Orange Book listing status must be assessed from the current FDA Orange Book record and relevant USPTO patent records. Patent listings can change through corrections, delistings, patent-term adjustments, or litigation outcomes. (U.S. Food and Drug Administration, 2024b; U.S. Patent and Trademark Office, 2024)

When does DICLEGIS lose exclusivity?

DICLEGIS had FDA approval in 2013, but approval date alone does not establish the end of patent exclusivity. The effective generic-entry date depends on:

• Listed patents in the Orange Book
• Regulatory exclusivity attached to the NDA
• Any Paragraph IV certification
• Litigation filed within the statutory period
• Settlement terms
• Patent-term adjustment or pediatric exclusivity
• Commercial launch provisions in an agreement

For an ANDA applicant, the relevant route is generally a Paragraph I, II, III, or IV certification for each listed patent. A Paragraph IV certification alleges that a listed patent is invalid, unenforceable, or will not be infringed. If the NDA holder brings suit within the statutory period, FDA approval may be subject to a 30-month stay, subject to statutory exceptions and court developments. (U.S. Food and Drug Administration, 2023)

No current generic-entry date should be inferred from the original 2013 approval date. The controlling source is the live Orange Book record combined with court dockets and any settlement agreement.

What is the Orange Book status of DICLEGIS?

The Orange Book identifies approved drug products, patent information submitted by NDA holders, and certain exclusivity information. For DICLEGIS, a diligence review should capture:

• NDA 021876
• Active ingredient and strength
• Delayed-release dosage form
• Listed patents
• Patent expiration dates
• Use codes for method-of-use patents
• Any active exclusivity codes
• Approved generic applications
• Applicant certifications and approval status

An Orange Book listing does not by itself prove that a patent will survive litigation. It establishes the regulatory framework for ANDA certification and potential entry delay.

The highest-value diligence item is the claim-to-product comparison. A formulation patent may cover a particular polymer, coating, dissolution window, or manufacturing sequence. A generic applicant can sometimes design around the claim while matching the reference product’s performance.

Which companies are challenging DICLEGIS?

Publicly reported challenge activity should be evaluated through FDA ANDA records, Paragraph IV notices, federal court dockets, and company filings. The relevant competitor categories are:

1. ANDA applicants seeking approval of doxylamine/pyridoxine delayed-release tablets.
2. 505(b)(2) applicants proposing modified strengths or different release technologies.
3. Manufacturers of alternative prenatal nausea products.
4. International suppliers commercializing doxylamine/pyridoxine products under different brand names.

A generic challenger does not need to reproduce every excipient. It must generally demonstrate pharmaceutical equivalence and bioequivalence to the reference product, subject to FDA requirements for the proposed dosage form. For a delayed-release product, comparative dissolution and pharmacokinetic performance are central.

What generic entry risks exist for DICLEGIS?

Generic substitution risk

The product has meaningful generic vulnerability because its active ingredients are established and inexpensive. The main barriers are formulation equivalence, regulatory documentation, patent claims, and commercial scale.

505(b)(2) risk

A 505(b)(2) applicant could pursue a different strength, dosing schedule, release profile, or delivery system. This pathway may be commercially relevant for:

• Once-daily dosing
• Lower tablet burden
• Alternative tablet or capsule formats
• Sprinkle or orally disintegrating products
• Pediatric or broader nausea indications, subject to clinical and regulatory support

Nonprescription risk

An OTC strategy would face substantial regulatory and commercial barriers. Pregnancy use creates a high need for clear labeling, physician confidence, and extensive safety communication. OTC conversion would require a separate FDA determination and cannot be assumed from the nonprescription availability of either active ingredient in other contexts.

How does DICLEGIS compare with BONJESTA?

BONJESTA contains 20 mg of doxylamine succinate and 20 mg of pyridoxine hydrochloride per extended-release tablet. It provides a higher-strength alternative within the same therapeutic category and may reduce tablet count for some patients. (U.S. Food and Drug Administration, 2024c)

Factor	DICLEGIS	BONJESTA
Doxylamine per tablet	10 mg	20 mg
Pyridoxine per tablet	10 mg	20 mg
Release description	Delayed release	Extended release
Commercial positioning	Flexible titration	Higher-strength dosing
Excipient opportunity	Low-dose uniformity and delayed release	High-dose release control and tablet burden
Generic risk	Established active ingredients and formulation challenge	Similar active-ingredient risk with separate product-specific barriers

A direct competitor cannot assume that approval or patent status for one product transfers to the other. Each product has its own application, labeling, formulation, and Orange Book record.

What licensing deals could create commercial opportunities?

The most practical licensing targets are technology platforms rather than the active ingredients. Potential deal structures include:

• Licensing a non-infringing delayed-release formulation
• Contract development and manufacturing for an ANDA sponsor
• Regional rights for DICLEGIS-equivalent products
• Excipient or coating technology licensing
• Supply agreements for specialized polymers
• Co-development of a lower-tablet-burden product
• Acquisition of manufacturing know-how or process patents

A licensing target is stronger when it provides one of three measurable benefits: faster bioequivalence development, lower cost of goods, or a credible design-around to listed patents.

What manufacturing and IP barriers affect DICLEGIS competitors?

The principal manufacturing barriers are low-dose content uniformity, coating consistency, dissolution reproducibility, and stability through shelf life. Pregnancy products also face elevated scrutiny over excipient identity, impurity controls, and batch consistency.

The most defensible technical package would combine:

• A distinct release-controlling system
• Demonstrated dissolution equivalence
• Robust scale-up data
• A lower-cost process
• A stable global excipient supply chain
• Patent claims directed to composition and process

A formulation that merely changes magnesium stearate or colorant is unlikely to create durable market exclusivity. A system that improves release control while reducing manufacturing complexity has greater licensing value.

What is the revenue exposure and competitive outlook?

DICLEGIS revenue is exposed to generic entry, physician switching, payer substitution, and competition from BONJESTA and non-branded doxylamine/pyridoxine products. Because the product treats a pregnancy-specific condition, market access depends heavily on obstetrician and maternal-fetal medicine prescribing behavior.

Commercial opportunities are strongest in four areas:

1. A lower-cost generic delayed-release tablet.
2. A reduced-pill-burden extended-release product.
3. A 505(b)(2) product with differentiated dosing or delivery.
4. Manufacturing technology that lowers cost while preserving the reference release profile.

Revenue modeling should use prescription volume, net price, payer mix, generic discounting, launch timing, and the number of approved competitors. Public company filings and IQVIA data are appropriate sources for current market estimates, while FDA records establish product and regulatory status.

Key Takeaways

• DICLEGIS is a 10 mg/10 mg delayed-release doxylamine/pyridoxine tablet approved for nausea and vomiting of pregnancy.
• Its commercial differentiation rests on formulation, release timing, dosing flexibility, and pregnancy-focused labeling.
• The core excipient system includes microcrystalline cellulose, magnesium trisilicate, croscarmellose sodium, magnesium stearate, hypromellose, polyethylene glycol, talc, titanium dioxide, and colorants.
• Modified-release polymers, coating systems, compression aids, and lubricant selection offer the main excipient-development opportunities.
• Generic risk is structurally significant because both active ingredients are established and inexpensive.
• Current patent expiration dates, Paragraph IV challenges, settlements, and generic entry dates must be taken from the live Orange Book and litigation records.
• The strongest commercial strategy is a non-infringing formulation with equivalent dissolution, lower manufacturing cost, and reduced tablet burden.

FAQs

Can DICLEGIS be reformulated without changing its FDA pathway?

Yes. A formulation that remains pharmaceutically equivalent may be suitable for an ANDA, while a materially different strength, release profile, or indication may require a 505(b)(2) application.

Which excipient is most important for DICLEGIS delayed release?

The release-controlling coating or polymer system is most important because it determines when doxylamine and pyridoxine become available for absorption.

Is a DICLEGIS generic required to use the same excipients?

No. A generic applicant generally may use different inactive ingredients if the product meets applicable pharmaceutical equivalence, bioequivalence, quality, labeling, and safety requirements.

Could an orally disintegrating DICLEGIS product compete commercially?

Potentially, but an orally disintegrating dosage form would need to preserve the intended delayed-release behavior. Faster disintegration alone would not establish equivalence to the reference product.

Are biosimilar risks relevant to DICLEGIS?

No. DICLEGIS is a small-molecule combination product, so the relevant competitors are generics and 505(b)(2) products rather than biosimilars.

References

1. U.S. Food and Drug Administration. (2024a). DICLEGIS (doxylamine succinate and pyridoxine hydrochloride) delayed-release tablets: Prescribing information.
2. U.S. Food and Drug Administration. (2024b). Approved drug products with therapeutic equivalence evaluations: Orange Book.
3. U.S. Food and Drug Administration. (2024c). BONJESTA (doxylamine succinate and pyridoxine hydrochloride) extended-release tablets: Prescribing information.
4. U.S. Food and Drug Administration. (2023). Guidance for industry: ANDAs for certain highly purified synthetic peptides.
5. U.S. Patent and Trademark Office. (2024). Patent Center and patent term adjustment records.