List of Excipients in Branded Drug CREXONT

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Amneal Pharmaceuticals LLC	CREXONT	carbidopa and levodopa	64896-967	ALCOHOL
Amneal Pharmaceuticals LLC	CREXONT	carbidopa and levodopa	64896-967	AMMONIA
Amneal Pharmaceuticals LLC	CREXONT	carbidopa and levodopa	64896-967	BUTYL ALCOHOL

CREXONT Excipient Strategy and Commercial Opportunities

Last updated: August 5, 2026

CREXONT is Amneal Pharmaceuticals’ extended-release carbidopa/levodopa capsule, approved by the FDA in August 2024 for Parkinson’s disease. Its commercial differentiation depends on a multiparticulate delivery system that combines immediate-release and extended-release drug fractions. The excipient opportunity is therefore concentrated in bead engineering, release control, capsule manufacture, process robustness, and generic design-around technology rather than in novel active pharmaceutical ingredients.

The main commercial opportunities are controlled-release excipient supply, multiparticulate coating services, analytical and bioequivalence support, formulation licensing, and manufacturing technologies that reproduce the pharmacokinetic profile without infringing Amneal’s formulation patents. CREXONT is a small-molecule product, so biosimilar risk is not applicable. Generic competition will depend on FDA approval of an abbreviated new drug application and the scope and enforceability of listed formulation and method-of-use patents.

What is CREXONT and how does its formulation work?

CREXONT contains carbidopa and levodopa in an extended-release capsule. It is available in three strengths:

CREXONT strength	Carbidopa	Levodopa
35 mg/140 mg	35 mg	140 mg
52.5 mg/210 mg	52.5 mg	210 mg
70 mg/280 mg	70 mg	280 mg

The product uses two release populations:

1. Immediate-release granules for an early levodopa exposure.
2. Extended-release pellets or multiparticulates intended to prolong levodopa exposure.

This design addresses a major limitation of conventional immediate-release carbidopa/levodopa: fluctuating plasma concentrations, wearing-off periods, and frequent dosing. CREXONT is administered orally, with dosing individualized according to response and tolerability. The FDA label identifies food effects, including delayed absorption and reduced exposure under certain high-fat meal conditions, as clinically relevant factors.[1]

The formulation strategy has three technical objectives:

• Deliver levodopa rapidly enough to reduce time to clinical response.
• Sustain exposure between doses.
• Maintain consistent release despite variation in gastrointestinal pH, transit time, food intake, and manufacturing conditions.

What excipients are used in CREXONT?

The FDA prescribing information identifies inactive ingredients used in CREXONT capsules, including common pharmaceutical excipients associated with granulation, flow, lubrication, coating, and capsule manufacture.[1]

Publicly disclosed excipient categories include:

Excipient category	Likely formulation function
Microcrystalline cellulose	Core diluent, compressibility, pellet structure
Mannitol	Diluent and processing aid
Hypromellose	Binder or release-controlling polymer
Povidone	Binder and granulation aid
Crospovidone	Disintegrant for rapid-release fractions
Colloidal silicon dioxide	Glidant and moisture-flow control
Magnesium stearate	Lubricant
Sodium lauryl sulfate	Wetting or dissolution aid
Talc	Anti-tacking and coating-process aid
Titanium dioxide and colorants	Capsule identification and appearance
Gelatin	Hard-capsule shell material

The public label does not disclose the quantitative percentage of each excipient, the specific grade of each material, the polymer molecular-weight distribution, or the coating-process parameters. Those undisclosed variables can be commercially important because multiparticulate drug products are sensitive to particle size, porosity, polymer viscosity, coating weight gain, curing conditions, and residual moisture.

Which excipients are most strategically important?

The highest-value excipient functions are likely to be:

Release-controlling polymers

Hypromellose and related hydrophilic polymers can control water penetration, gel formation, and drug diffusion. Commercial value depends on polymer grade, viscosity, particle size, substitution pattern, and compatibility with levodopa and carbidopa.

A supplier that can provide tight lot-to-lot control may have an advantage over a lower-cost commodity supplier. A change in polymer viscosity or particle morphology can alter dissolution profiles and potentially trigger a regulatory comparability exercise.

Pellet-core excipients

Microcrystalline cellulose, mannitol, binders, and wetting agents determine the density, porosity, friability, and drug loading of the multiparticulate core. These properties affect coating uniformity and release kinetics.

Core materials with narrow particle-size distributions can reduce process variation during extrusion-spheronization, layering, or fluid-bed processing.

Coating excipients

The extended-release fraction likely depends on a polymeric coating system or a matrix architecture. Coating suppliers can compete through:

• Film-forming polymers.
• Plasticizers.
• Anti-tacking agents.
• Pore formers.
• Colorants.
• Functional coatings that resist premature drug release.

The commercial opportunity is strongest where the supplier provides both the excipient and validated process support.

Capsule-shell materials

Capsule shell color, opacity, mechanical strength, and moisture transmission are relevant to product identification and stability. Capsule suppliers may compete on high-speed filling performance, defect reduction, and compatibility with multiparticulate fills.

What formulation patents protect CREXONT?

CREXONT’s principal intellectual-property value is expected to reside in formulation and delivery-system claims rather than composition-of-matter claims covering carbidopa or levodopa. Both active ingredients are longstanding generic compounds.

Potential patent claim categories include:

• Capsules containing immediate-release and extended-release carbidopa/levodopa populations.
• Multiparticulate or pellet-based dosage forms.
• Specific drug-to-polymer ratios.
• Coating thickness or coating weight gain.
• Dissolution profiles.
• Pharmacokinetic parameters.
• Dosing methods for reducing wearing-off.
• Conversion from immediate-release carbidopa/levodopa.
• Manufacturing processes for producing coated pellets.
• Stability and moisture-control configurations.

The commercial strength of these patents depends on claim breadth and whether a generic applicant can alter the polymer, pellet structure, release profile, capsule configuration, or dosing instructions while achieving FDA approval.

The key distinction is between broad platform claims and narrow implementation claims. A broad claim covering a capsule with both immediate-release and extended-release carbidopa/levodopa fractions could create a meaningful barrier. A narrow claim limited to a particular polymer grade, coating ratio, or dissolution range may be easier to design around.

Patent numbers and Orange Book listing status should be evaluated against the current FDA Orange Book and the applicable patent-family prosecution records. Public product materials alone do not establish the complete patent estate or the enforceability of every claim.

What is the Orange Book status of CREXONT?

CREXONT was approved under NDA 216962.[2] As a small-molecule prescription drug approved under the Federal Food, Drug, and Cosmetic Act, it is eligible for Orange Book patent listing if Amneal submits patents that meet FDA listing criteria.

The relevant Orange Book categories may include:

Patent type	Commercial effect
Drug-product patent	Can delay or complicate generic approval
Formulation patent	Targets release architecture, excipient system, or dosage form
Method-of-use patent	May protect a labeled Parkinson’s disease dosing method
Manufacturing patent	Usually has less direct effect on ANDA approval unless linked to product claims
Process patent not eligible for listing	May support separate litigation but generally does not block ANDA approval by itself

A patent listed in the Orange Book does not establish that the patent is valid or infringed. It gives the innovator a basis to pursue statutory patent litigation after a Paragraph IV certification.

When does CREXONT lose exclusivity?

CREXONT’s regulatory exclusivity and patent exclusivity are separate.

Exclusivity element	Timing or status
FDA approval	August 2024
New chemical entity exclusivity	Not expected because carbidopa and levodopa are established active ingredients
Three-year clinical-investigation exclusivity	Possible only for qualifying new clinical investigations supporting approval
Orphan-drug exclusivity	Not indicated by the approved Parkinson’s disease use
Patent exclusivity	Depends on issued, listed patents and patent-term adjustments
Generic entry	Depends on ANDA approval, certifications, litigation, and settlements

Because CREXONT uses old active ingredients, its principal protection is likely to come from formulation patents, method-of-use patents, regulatory exclusivity associated with qualifying clinical investigations, and manufacturing know-how.

A generic applicant could seek approval through an ANDA if it can demonstrate pharmaceutical equivalence and bioequivalence or otherwise satisfy FDA requirements for a modified-release product. The ANDA applicant would need to address listed patents through Paragraph II, III, or IV certifications.

What Paragraph IV challenges could affect CREXONT?

A Paragraph IV certification asserts that a listed patent is invalid, unenforceable, or not infringed. If Amneal sues within the statutory period, FDA approval can be subject to a 30-month stay, subject to statutory exceptions and litigation outcomes.[3]

Likely Paragraph IV pressure points include:

• Whether a generic uses the same immediate-release and extended-release architecture.
• Whether dissolution results fall within a claimed range.
• Whether the generic uses an equivalent polymer system.
• Whether a method-of-use patent can be avoided through a section viii statement.
• Whether the generic can rely on a different dosing instruction.
• Whether the patent claims are obvious in view of earlier carbidopa/levodopa controlled-release products.

The greatest litigation risk is likely to arise from formulation patents that claim functional performance, such as dissolution or exposure profiles. Such claims can be difficult to design around if FDA bioequivalence requirements effectively force a generic toward similar release behavior.

What generic entry risks exist for CREXONT?

CREXONT faces generic risk from three principal pathways.

Direct multiparticulate ANDA

A competitor could replicate the overall release architecture using different excipients or different coating processes. This route creates the highest patent risk but may offer the closest clinical and commercial substitute.

Alternative extended-release formulation

A generic applicant could develop a different matrix, coated-pellet, or osmotic design. The product would still need to meet FDA requirements for strength, release performance, and bioequivalence. A sufficiently different design could reduce infringement exposure but increase development risk.

Conventional levodopa substitution

Physicians may use immediate-release carbidopa/levodopa, controlled-release tablets, or other levodopa products as alternatives. These products may not be therapeutically interchangeable with CREXONT, but they create price pressure and can limit the premium available to an extended-release capsule.

The main technical barrier is not simply reproducing the dose. It is matching the clinical exposure profile while controlling food effects, dose-to-dose variability, and capsule fill uniformity.

What commercial opportunities exist for excipient suppliers?

Controlled-release excipient supply

Suppliers of hypromellose, methacrylate polymers, ethylcellulose, pore formers, plasticizers, and coating aids can target the CREXONT ecosystem. The strongest value proposition is a complete controlled-release platform supported by dissolution modeling and scale-up data.

Multiparticulate manufacturing

Contract development and manufacturing organizations can offer:

• Drug layering.
• Extrusion and spheronization.
• Fluid-bed coating.
• Pellet classification.
• Capsule filling.
• In-process particle-size control.
• Dissolution method development.

A CDMO with experience in low-dose, high-potency, or moisture-sensitive multiparticulates may be positioned to support generic or lifecycle-management programs.

Analytical and bioequivalence services

Commercial demand is likely for:

• Discriminating dissolution methods.
• Multiparticulate assay and content-uniformity testing.
• Polymer characterization.
• In vitro-in vivo correlation.
• Food-effect assessment.
• Bioequivalence study design.
• Stability testing under ICH conditions.

Because modified-release products can fail bioequivalence despite matching nominal strength, analytical capability is a central competitive factor.

Excipient-based design-around licensing

A polymer supplier or formulation company could license a release-control platform that avoids Amneal’s claims. The most defensible platform would combine:

• A distinct polymer system.
• A different pellet-core architecture.
• A validated dissolution profile.
• Freedom-to-operate analysis.
• Scale-up and stability data.

The value of such a license would depend on whether it reduces Paragraph IV litigation risk while preserving FDA approval prospects.

How strong is the CREXONT patent estate?

CREXONT has a potentially meaningful formulation patent position because the product depends on a specialized multiparticulate delivery system. Its strength should be assessed across five dimensions:

Factor	Assessment
Active-ingredient protection	Weak or unavailable because carbidopa and levodopa are old compounds
Formulation differentiation	Potentially strong if claims cover the combined release architecture
Manufacturing know-how	Potentially important but harder to use as an ANDA barrier
Method-of-use protection	Dependent on claim scope and available section viii pathways
Design-around risk	Material because alternative polymers and pellet systems may be feasible

The estate is stronger if patents claim measurable product attributes that a generic must reproduce to obtain approval. It is weaker if claims depend on narrow excipient identities or process steps that a competitor can readily replace.

What licensing deals affect CREXONT?

CREXONT was developed and commercialized by Amneal Pharmaceuticals through its proprietary IPX203 technology. Public commercial materials identify the product as an Amneal product rather than as a licensed asset from a large multinational innovator.[4]

The licensing opportunity is therefore more likely to involve downstream platform transactions than an existing originator-to-originator deal. Potential counterparties include:

• Controlled-release polymer suppliers.
• Specialty CDMOs.
• Generic manufacturers.
• Parkinson’s disease commercial partners.
• Regional distributors.
• Companies seeking rights to multiparticulate delivery technology.

No public licensing arrangement should be treated as material to CREXONT’s freedom to operate unless it is disclosed in SEC filings, FDA records, patent assignments, or transaction documents.

What FDA regulatory issues affect excipient commercialization?

Excipient changes can affect regulatory status even when the active ingredients remain unchanged. Risk areas include:

• Modified dissolution profiles.
• Changes in food-effect behavior.
• Capsule fill-weight variation.
• Drug-excipient compatibility.
• Residual solvents.
• Nitrosamine or elemental impurity controls.
• Moisture uptake.
• Polymer lot variability.
• Stability after scale-up.
• Differences in particle-size distribution.

For an approved product, a change in excipient supplier or grade may require comparability data and could trigger a postapproval supplement. For an ANDA, the proposed formulation must satisfy the applicable sameness and bioequivalence requirements. The excipient must also be acceptable for the route, dosage form, and exposure level.

Is biosimilar competition relevant to CREXONT?

No. CREXONT is a small-molecule drug, not a biologic. Biosimilar approval under the Public Health Service Act is not the relevant competitive pathway.

The relevant competitors are:

• Generic carbidopa/levodopa products.
• Extended-release carbidopa/levodopa products.
• Other levodopa delivery technologies.
• Continuous intestinal or subcutaneous dopaminergic therapies.
• Future oral or nonoral Parkinson’s disease treatments.

Key Takeaways

• CREXONT’s commercial differentiation comes from an immediate-release and extended-release multiparticulate carbidopa/levodopa system.
• The highest-value excipient opportunities involve release-control polymers, pellet-core materials, coating systems, capsule manufacture, and analytical support.
• Carbidopa and levodopa do not provide meaningful composition-of-matter protection because both are established active ingredients.
• Patent value is likely concentrated in formulation, pharmacokinetic, method-of-use, and manufacturing claims.
• Generic risk will depend on Orange Book listings, Paragraph IV certifications, bioequivalence requirements, and the feasibility of excipient-based design-around strategies.
• Biosimilar competition is irrelevant; CREXONT faces conventional generic and therapeutic-substitution risk.
• Excipient suppliers with validated controlled-release platforms and scale-up expertise have the strongest commercial positioning.
• Quantitative excipient composition and process parameters are not fully disclosed in the FDA label, making manufacturing know-how a potentially important barrier.

FAQs

Can a generic use different excipients from CREXONT?

Yes. A generic may use different inactive ingredients if it meets FDA requirements for pharmaceutical equivalence, bioequivalence, safety, and product performance. Different excipients can also support a noninfringing formulation strategy.

Which excipient is most likely to control CREXONT’s release profile?

The release-controlling polymer system is likely to have the greatest effect, but pellet porosity, coating thickness, plasticizer content, pore-former level, and manufacturing conditions can materially change dissolution.

Can an excipient supplier patent a CREXONT alternative?

Yes. A supplier or formulation company may patent a distinct polymer combination, pellet structure, coating system, dissolution profile, or manufacturing process. Patentability will depend on novelty, nonobviousness, written description, and claim scope.

Does a change in capsule color create meaningful patent protection?

Usually not. Capsule color and shell composition can support product identification, quality control, and trade dress, but they generally provide weaker protection than release-system and formulation claims.

Can CREXONT be substituted automatically with generic carbidopa/levodopa?

Substitution depends on the generic product’s FDA rating, dosage form, strength, release characteristics, state pharmacy law, and prescriber instructions. Immediate-release or other extended-release products should not be assumed to be therapeutically interchangeable solely because they contain the same active ingredients.

References

1. U.S. Food and Drug Administration. (2024). CREXONT (carbidopa and levodopa) extended-release capsules: Prescribing information. https://www.accessdata.fda.gov
2. U.S. Food and Drug Administration. (2024). CREXONT approval history and NDA 216962. https://www.accessdata.fda.gov
3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book
4. Amneal Pharmaceuticals, Inc. (2024). CREXONT product information and investor disclosures. https://investors.amneal.com