List of Excipients in Branded Drug DELZICOL

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Allergan Inc	DELZICOL	mesalamine	0023-5853	DIBUTYL SEBACATE
Allergan Inc	DELZICOL	mesalamine	0023-5853	FERRIC OXIDE RED
Allergan Inc	DELZICOL	mesalamine	0023-5853	FERRIC OXIDE YELLOW
Allergan Inc	DELZICOL	mesalamine	0023-5853	HYPROMELLOSES
Allergan Inc	DELZICOL	mesalamine	0023-5853	LACTOSE MONOHYDRATE
Allergan Inc	DELZICOL	mesalamine	0023-5853	MAGNESIUM STEARATE
Allergan Inc	DELZICOL	mesalamine	0023-5853	METHACRYLIC ACID - METHYL METHACRYLATE COPOLYMER

DELZICOL Excipient Strategy and Commercial Opportunities

Last updated: September 16, 2026

Delzicol is a 400 mg delayed-release mesalamine capsule approved for ulcerative colitis in adults and pediatric patients aged five years and older. Its commercial value depends less on the active ingredient, which is widely available, than on reproducing the product’s enteric-release behavior, capsule architecture, stability profile, and bioequivalence performance. The strongest opportunities are generic or alternative delayed-release capsules, excipient-substituted formulations, pediatric dose optimization, and contract manufacturing of pH-dependent multiparticulate systems.

What is Delzicol and how does its formulation work?

Delzicol is an oral delayed-release capsule containing mesalamine, also known as 5-aminosalicylic acid. The formulation is designed to prevent substantial drug release in the stomach and promote release in the intestinal tract, where mesalamine acts locally on the colonic mucosa.

The U.S. product is marketed in a 400 mg capsule strength. The FDA-approved indication covers:

• Induction of remission in mildly to moderately active ulcerative colitis.
• Maintenance of remission in ulcerative colitis.
• Treatment of adult and pediatric patients aged five years and older, subject to labeling-specific dosing requirements.[1]

Delzicol was approved under NDA 204412 in 2013.[1] It was developed as a replacement for Asacol delayed-release tablets, whose formulation raised concerns associated with dibutyl phthalate in the tablet coating. Delzicol uses a capsule-based delivery system rather than the former Asacol tablet platform.

What excipients are used in Delzicol?

The Delzicol label identifies a multipart excipient system that includes materials used for capsule manufacture, pellet or granule formation, enteric protection, lubrication, flow control, and coating performance. Public labeling identifies excipient classes and components including:

Formulation function	Representative Delzicol excipient components
Capsule shell	Gelatin, titanium dioxide and colorants
Core processing	Microcrystalline cellulose, povidone and crospovidone
Lubrication and flow	Magnesium stearate and colloidal silicon dioxide
Enteric coating	Methacrylic acid-based copolymer, talc and triethyl citrate
Processing and release control	Hypromellose, sodium lauryl sulfate and related coating or granulation aids

The exact commercial composition should be taken from the current FDA-approved prescribing information and drug-labeling record because suppliers, colorants and nonfunctional processing aids can change across manufacturing sites.[1,2]

The key formulation insight is that Delzicol is not a simple powder-filled capsule. The excipients operate as a coordinated system. Changing the polymer, plasticizer, coating weight, pellet size distribution or capsule shell can alter:

• Acid resistance.
• Intestinal release onset.
• Release rate at higher pH.
• Moisture sensitivity.
• Capsule disintegration.
• Long-term stability.
• Food-effect behavior.
• Bioequivalence results.

Why is the excipient system commercially important?

Mesalamine is a mature active pharmaceutical ingredient with multiple approved oral delivery systems. The commercial barrier is therefore formulation performance rather than API exclusivity.

An excipient strategy for a Delzicol competitor must solve four technical problems:

1. Protect mesalamine from premature gastric release.
2. Produce reproducible release after exposure to intestinal pH.
3. Maintain dose uniformity across multiparticulate units.
4. Demonstrate equivalent systemic exposure and local gastrointestinal performance.

The most commercially defensible formulation may not copy every Delzicol excipient. It must instead reproduce the critical quality attributes that determine release and clinical performance.

Which excipients are most strategically important?

Enteric polymer

The enteric polymer is the highest-value excipient in the system. Methacrylic acid copolymers provide pH-dependent dissolution. Polymer grade, particle size, neutralization behavior, coating thickness and supplier variability can materially affect release.

A developer can pursue either:

• A close Q1/Q2 approach using the same or functionally equivalent polymer system.
• A differentiated system using another methacrylic acid copolymer grade.
• A hybrid coating using polymer blends to adjust acid resistance and intestinal release.

A close-copy approach reduces development risk but increases dependence on incumbent suppliers and may create more direct formulation-comparison issues. A differentiated approach can support intellectual property and supply resilience but requires more dissolution and bioequivalence work.

Plasticizer

Triethyl citrate and comparable plasticizers affect film flexibility, cracking resistance and drug-release consistency. Excess plasticizer can soften the coating and change permeability. Insufficient plasticizer can increase film brittleness and create dose-dumping or stability risks.

A commercial formulation should evaluate plasticizer concentration against:

• Coating integrity after accelerated storage.
• Mechanical stress during capsule handling.
• Release after exposure to gastric acid.
• Release after transition to intestinal pH.
• Compatibility with the enteric polymer and talc.

Capsule shell

The capsule shell affects moisture transmission, disintegration and patient acceptability. Gelatin capsules are familiar to regulators and patients, but they introduce animal-origin, moisture and supply-chain considerations.

Potential alternatives include:

• Hypromellose capsules for vegetarian positioning.
• Low-moisture capsule systems for improved stability.
• Colorant-minimized shells for clean-label or regional markets.
• Capsules compatible with automated filling and high-speed inspection.

A shell change is not commercially neutral. It can affect dissolution, storage behavior, capsule brittleness and the regulatory comparability package.

Lubricants and glidants

Magnesium stearate, colloidal silicon dioxide and related processing aids affect powder flow, fill-weight uniformity and manufacturing throughput. Excessive magnesium stearate can impair wetting and dissolution. Excessive glidant can change blend behavior and segregation risk.

These excipients create a manufacturing tradeoff between reliable encapsulation and rapid drug release after the coating dissolves.

What commercial opportunities exist for Delzicol excipient innovation?

1. Generic 400 mg delayed-release capsules

The largest opportunity is an ANDA product that matches Delzicol’s dosage form, strength, route and release behavior. The target product would compete on:

• Lower acquisition cost.
• Reliable wholesaler supply.
• Formulary placement.
• Reduced back-order exposure.
• Consistent reimbursement coding.

A generic applicant would need a robust bioequivalence and dissolution package. For a locally acting gastrointestinal product, conventional plasma pharmacokinetics may not fully capture formulation performance. Comparative dissolution, pharmacokinetic data and FDA-specific product requirements are central to development.[3]

2. Pediatric dose flexibility

Delzicol is labeled for pediatric patients aged five years and older, but 400 mg capsules can create dosing complexity in younger or lower-weight patients. Commercial opportunities include:

• Lower-strength capsules.
• Mini-capsules.
• Sprinkleable multiparticulates.
• Sachets containing enteric-coated granules.
• Flexible capsule-opening instructions where supported by stability and labeling data.

Any pediatric adaptation must preserve enteric protection. Opening a capsule and exposing coated particles to food, liquids or crushing can change the release profile and dosing accuracy.

3. Excipient-substituted products

Excipient substitution can create differentiated products for markets that restrict particular materials. Potential positioning includes:

• Phthalate-free formulations.
• Gelatin-free capsules.
• Reduced-colorant products.
• Low-allergen formulations.
• Products using non-animal-derived excipients.
• Products designed for lower moisture sensitivity.

The commercial value is strongest when the substitution solves a real procurement or regulatory problem without compromising the release profile.

4. Regional manufacturing and supply-chain resilience

The enteric polymer, coating equipment and capsule shell are potential supply bottlenecks. A second-source strategy can have value even where the finished product is not differentiated.

Manufacturers can build commercial advantage through:

• Dual sourcing of methacrylic acid copolymers.
• Validated alternative plasticizer suppliers.
• Regional capsule-shell production.
• Local coating capacity.
• Controlled particle-size specifications.
• Reduced dependence on a single contract manufacturer.

For mature generic products, supply reliability can be more important than minor formulation differences.

5. Reformulated combination and adherence products

Mesalamine patients may take multiple daily doses. Opportunities include dose-consolidated regimens, provided the total daily exposure and release characteristics support an approved clinical and regulatory strategy.

Potential development concepts include:

• Higher-strength delayed-release capsules.
• Once-daily mesalamine products.
• Combination packs for induction and maintenance.
• Adherence-oriented packaging.
• Calendar blister systems.

These products would compete with existing once-daily mesalamine formulations, including Apriso, Lialda and other mesalamine delivery systems. The excipient challenge is to maintain colonic delivery while supporting a larger drug load.

What patents protect Delzicol?

Delzicol’s principal commercial protection has historically been formulation and dosage-form based rather than based on new chemical entity protection for mesalamine. Mesalamine has been used clinically for decades, and multiple companies have developed distinct oral delivery platforms.

Relevant intellectual-property categories include:

IP category	Potential subject matter	Commercial relevance
Composition patents	Specific excipient combinations or coated multiparticulates	May restrict close-copy formulations
Formulation patents	Capsule architecture, coating layers and release profiles	Can affect ANDA design-around strategy
Method-of-use patents	Dosing regimens or treatment of ulcerative colitis	Usually narrower than formulation rights
Manufacturing patents	Coating process, drying conditions and particle engineering	Can create process barriers
Trademark rights	Delzicol brand and trade dress	Relevant to launch naming, not formulation freedom

The current Orange Book status must be assessed against the FDA’s live product-specific listings rather than historical patent databases. Patent expiry, pediatric exclusivity, regulatory exclusivity and listing status can change the launch analysis.[4]

A competitor should review:

• NDA 204412.
• Current Orange Book patent listings.
• Patent term adjustment.
• Patent term extension.
• Any Paragraph IV certifications.
• Active district-court or Federal Circuit litigation.
• Settlement agreements affecting generic launch dates.

No launch date should be inferred solely from the approval date. Delzicol was approved in 2013, but approval timing does not by itself establish the expiration of formulation patents or any generic-entry restriction.

When does Delzicol lose exclusivity?

Mesalamine is not protected by new chemical entity exclusivity in the same way as a newly discovered active ingredient. Delzicol’s practical exclusivity has depended on its dosage form, formulation, regulatory status and any listed patents.

The relevant milestones are:

Milestone	Delzicol significance
2013 NDA approval	FDA approval of Delzicol delayed-release capsules
Post-approval period	Potential product-specific regulatory exclusivity and patent enforcement
Patent expiry	Depends on each listed patent and adjusted term
ANDA approval	Requires FDA approval of a therapeutically equivalent product
Generic launch	Depends on patent certifications, litigation and settlement terms

A generic applicant can challenge listed patents through a Paragraph IV certification. The reference product sponsor may then file patent litigation, which can trigger a statutory stay of ANDA approval for up to 30 months, subject to statutory exceptions and court developments.[5]

What FDA regulatory issues affect a Delzicol generic?

The principal regulatory risks are formulation comparability and release performance.

A generic developer should establish:

• Assay and content uniformity.
• Acid-stage resistance.
• Buffer-stage dissolution.
• Multiparticulate size distribution.
• Coating weight uniformity.
• Moisture content.
• Capsule disintegration.
• Stability under long-term and accelerated conditions.
• Comparative bioavailability or bioequivalence.
• Compatibility with proposed labeling and administration instructions.

The development program should test the product under multiple dissolution conditions. A formulation that passes one pH condition but releases too slowly or too rapidly after transition to intestinal conditions may fail to demonstrate equivalence.

Manufacturing-process controls are also important. Enteric coating variability can arise from spray rate, inlet temperature, atomization pressure, bed temperature, polymer solids concentration and curing conditions.

How strong is the Delzicol patent estate?

The commercial strength of the Delzicol estate is likely to be moderate rather than absolute because:

• Mesalamine is a mature compound.
• Multiple competing formulations are approved.
• The formulation uses established excipient technologies.
• Design-around opportunities exist through polymer grade, coating architecture and capsule configuration.
• The product’s clinical value depends on release location and tolerability, not a new active mechanism.

The estate becomes stronger if it protects a narrow but difficult-to-reproduce combination of coating composition, release profile and manufacturing process. It becomes weaker when claims cover conventional enteric polymers and routine capsule excipients without a distinctive technical effect.

Which companies compete with Delzicol?

Delzicol competes within a broad mesalamine market rather than against a single product. Relevant competitors include:

Product or platform	Delivery concept	Competitive issue
Delzicol	Delayed-release 400 mg capsule	Reference product for formulation-focused competition
Lialda	Extended-release mesalamine tablet	Once-daily positioning and larger tablet platform
Apriso	Extended-release mesalamine capsule	Direct capsule and modified-release competition
Asacol HD	Delayed-release mesalamine tablet	Historical and formulation-platform relevance
Pentasa	Controlled-release mesalamine granules/capsules	Distinct release throughout the gastrointestinal tract
Generic mesalamine products	Multiple tablets, capsules and granules	Price pressure and formulary substitution

Commercial success depends on whether a product is positioned for induction, maintenance, pediatric use, once-daily dosing or lower acquisition cost.

What generic launch risks exist?

The primary launch risks are:

1. Paragraph IV litigation.
2. Failure to match dissolution and pharmacokinetic performance.
3. Manufacturing variability in enteric coating.
4. Supply disruption involving polymer or capsule-shell suppliers.
5. Payer preference for lower-cost alternatives.
6. Patient switching issues related to dosing frequency or capsule size.
7. Inability to support pediatric administration requirements.
8. Patent claims covering a manufacturing step rather than the final dosage form.

A design-around strategy should avoid unnecessary dependence on the reference product’s exact excipient ratios while maintaining the same critical release characteristics.

Key Takeaways

• Delzicol is a 400 mg delayed-release mesalamine capsule approved under NDA 204412 in 2013.
• The primary formulation challenge is coordinated pH-dependent release, not API novelty.
• Enteric polymer selection, plasticizer level, coating weight and capsule-shell choice are the highest-value excipient decisions.
• The strongest commercial opportunity is a reliable generic or differentiated delayed-release capsule with validated dissolution and bioequivalence.
• Pediatric dose flexibility, phthalate-free positioning, gelatin-free shells and supply-chain resilience provide secondary opportunities.
• Patent exposure must be assessed through current Orange Book listings, patent-term data, Paragraph IV certifications and litigation records.
• The Delzicol patent estate is more likely to be vulnerable to design-around strategies than a new chemical entity estate, but manufacturing and release-profile claims can still delay market entry.
• Commercial competition includes Lialda, Apriso, Asacol HD, Pentasa and other generic mesalamine platforms.

Frequently Asked Questions

Can Delzicol excipients be replaced in a generic formulation?

Yes. A generic does not necessarily need to use identical excipients, but the substituted formulation must meet applicable pharmaceutical equivalence, bioequivalence, dissolution, stability and quality requirements.

Is Delzicol a biologic or does it face biosimilar competition?

No. Delzicol contains the small-molecule drug mesalamine. It faces generic competition through the ANDA pathway, not biosimilar competition under the Public Health Service Act.

What is the main technical barrier to copying Delzicol?

The main barrier is reproducing the delayed-release profile across gastric and intestinal conditions while maintaining dose uniformity, stability and bioequivalence.

Can a Delzicol capsule be opened and mixed with food?

Administration instructions must follow the current FDA-approved labeling. Opening, crushing or dispersing a delayed-release product can change coating integrity and release behavior unless the label specifically permits that method.

Does a different enteric polymer create freedom to operate?

Not necessarily. A different polymer may support a design-around, but freedom to operate requires review of composition, formulation, method-of-use and manufacturing patent claims in each relevant jurisdiction.

References

1. U.S. Food and Drug Administration. (2024). Delzicol (mesalamine) delayed-release capsules: Prescribing information.
2. National Library of Medicine. (2024). DailyMed: Delzicol mesalamine delayed-release capsules.
3. U.S. Food and Drug Administration. (2022). Draft guidance on mesalamine oral dosage forms: Product-specific recommendations.
4. U.S. Food and Drug Administration. (2025). Approved drug products with therapeutic equivalence evaluations, Orange Book.
5. U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act of 1984, 21 U.S.C. § 355(j).