List of Excipients in Branded Drug KATERZIA

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Azurity Pharmaceuticals Inc	KATERZIA	amlodipine	52652-5001	CITRIC ACID MONOHYDRATE	2039-04-11
Azurity Pharmaceuticals Inc	KATERZIA	amlodipine	52652-5001	HYPROMELLOSE	2039-04-11
Azurity Pharmaceuticals Inc	KATERZIA	amlodipine	52652-5001	MALTODEXTRIN	2039-04-11
Azurity Pharmaceuticals Inc	KATERZIA	amlodipine	52652-5001	POLYSORBATE 80	2039-04-11
Azurity Pharmaceuticals Inc	KATERZIA	amlodipine	52652-5001	SILICON DIOXIDE	2039-04-11

Katerzia Excipient Strategy and Commercial Opportunities in Amlodipine Oral Suspension

Last updated: August 4, 2026

Katerzia is a 1 mg/mL oral suspension of amlodipine besylate developed for patients who cannot reliably swallow tablets, including pediatric patients. Its commercial differentiation depends less on the active ingredient than on excipient-controlled palatability, dose uniformity, physical stability, preservative performance, and administration-device usability. The main opportunities are generic or follow-on oral suspensions, improved pediatric formulations, alternative flavor systems, preservative-free presentations, and institutional products with lower administration costs.

What is Katerzia and how does its formulation differ from amlodipine tablets?

Katerzia contains amlodipine besylate equivalent to 1 mg of amlodipine per mL. It is an immediate-release oral suspension indicated for hypertension in adults and pediatric patients six years of age and older. The product is supplied with an oral dosing syringe and requires shaking before use. The FDA approved Katerzia under NDA 214439 in 2021 through the 505(b)(2) pathway, relying in part on established amlodipine safety and efficacy information.[1]

Attribute	Katerzia
Active ingredient	Amlodipine besylate
Strength	1 mg/mL amlodipine equivalent
Dosage form	Immediate-release oral suspension
Primary use	Hypertension
Pediatric use	Patients 6 years and older
Regulatory pathway	505(b)(2) NDA
Sponsor	Azurity Pharmaceuticals
Original FDA approval	2021
Administration	Oral syringe
Storage	Controlled room temperature under the approved label
Key use case	Patients unable to swallow tablets

Amlodipine tablets have a long-established generic market. Katerzia addresses a different administration problem: tablets cannot be easily titrated or administered to patients who need liquid dosing. The suspension also creates a product category where excipient design directly affects clinical usability.

What excipients are used in Katerzia?

Katerzia’s inactive ingredients are designed to support suspension stability, viscosity control, taste masking, preservation, and dose delivery. The FDA prescribing information identifies excipients including suspending and viscosity-modifying materials, buffering agents, a chelating agent, humectants, sweetener, preservative, flavoring, and purified water.[1]

Public labeling identifies the following excipient classes and components:

Excipient or excipient class	Likely formulation function
Microcrystalline cellulose and carmellose sodium	Structured suspension vehicle and sedimentation control
Hypromellose	Viscosity enhancement and particle suspension
Glycerin	Humectant and mouthfeel modifier
Citric acid and sodium citrate	Buffering and pH control
Disodium edetate	Chelation and preservative-support function
Methylparaben	Antimicrobial preservation
Sucralose	Sweetness and taste masking
Raspberry flavor	Palatability improvement
Purified water	Continuous aqueous phase

The exact commercial value lies in the combination rather than in any individual excipient. A cellulose-based structured vehicle can maintain uniformity after shaking while keeping viscosity low enough for an oral syringe. Buffer selection affects amlodipine stability, preservative efficacy, flavor perception, and container compatibility. Sucralose and raspberry flavor address the bitterness and medicinal taste associated with an active pharmaceutical ingredient that is difficult to administer chronically to children.

How does Katerzia’s excipient strategy support pediatric adherence?

Pediatric liquid medicines are subject to practical failure modes that do not appear in tablet products. Children may reject a formulation because of bitterness, aftertaste, mouthfeel, excessive viscosity, or flavor intensity. Caregivers may also administer inaccurate doses if the suspension settles rapidly or if the product does not flow consistently through the dosing syringe.

Katerzia’s formulation strategy addresses four linked requirements:

1. The suspension must remain physically uniform long enough for routine dosing.
2. The product must redisperse with ordinary shaking.
3. The liquid must pass through an oral syringe without excessive force.
4. The flavor and sweetness must support repeated administration.

The cellulose and polymer system is commercially important because a suspension that settles quickly can produce a low-dose supernatant followed by a concentrated sediment. Excessive viscosity creates a different risk: incomplete syringe withdrawal, residue in the bottle, and caregiver dosing errors.

The formulation therefore has a design tradeoff between sedimentation resistance and delivery force. A follow-on product that improves one parameter while worsening the other may fail to achieve practical equivalence even if the active ingredient concentration is identical.

What formulation attributes create commercial opportunities around Katerzia?

Taste and flavor systems

Katerzia uses a sweetener and fruit flavor system. Competitors could pursue alternative profiles such as strawberry, cherry, grape, vanilla, or flavorless formulations. The commercial opportunity is strongest in pediatric subgroups with differing flavor preferences and in patients who receive multiple chronic medicines.

Flavor changes can affect more than acceptance. They may alter pH perception, preservative performance, container adsorption, and the apparent bitterness of amlodipine. A successful alternative requires human palatability data, not only analytical flavor matching.

Preservative systems

Katerzia uses methylparaben according to public labeling. A competing formulation could investigate potassium sorbate, benzoate systems, phenoxyethanol, or preservative-free packaging. Each approach carries different technical constraints.

Preservative-free products could target:

• Infants or medically complex children with excipient sensitivity concerns
• Hospital and specialty-pharmacy use
• Single-dose or unit-dose packaging
• Patients receiving multiple preserved liquid medicines

The main barriers are multidose microbiological protection, in-use stability, packaging cost, and validated administration after opening. A preservative-free product is commercially attractive only if the packaging system reduces contamination risk without making the product materially more expensive.

Suspending-agent systems

Cellulose combinations are established tools for oral suspensions, but alternative systems can be developed using xanthan gum, carbomers, starch derivatives, silica-containing systems, or other pharmaceutical-grade polymers. The commercial objective is not simply to prevent sedimentation. It is to optimize:

• Redispersion after storage
• Sedimentation volume
• Syringe withdrawal force
• Dose uniformity
• Mouthfeel
• Pourability
• Manufacturing robustness

A lower-viscosity system may improve administration but increase settling. A highly structured vehicle may improve uniformity but produce unacceptable mouthfeel or dosing resistance.

Buffer and pH systems

Amlodipine formulation development must control pH, chemical stability, preservative activity, and taste. Citrate buffering is commercially familiar, but competing products could evaluate phosphate, acetate, or other systems where compatible with stability and safety requirements.

Buffer selection can create formulation differentiation without changing the active ingredient. It can also generate patentable combinations if the sponsor demonstrates a defined stability, taste, redispersibility, or preservative-performance advantage.

Device and container integration

The dosing syringe is part of the product’s commercial performance. Opportunities include:

• Low-friction oral syringes
• Syringes with dose markings optimized for pediatric titration
• Bottle adapters that reduce spillage
• Unit-dose sachets or cups
• Child-resistant bottles with easier caregiver access
• Packaging that limits oxygen or light exposure
• Connected dosing aids for adherence monitoring

Device differentiation may support a combination-product strategy, although the regulatory burden rises if the device has a substantive dosing or delivery function.

What patents protect Katerzia and its excipient formulation?

Katerzia was approved through an NDA rather than as a conventional new chemical entity product. Amlodipine itself has extensive prior art and a mature generic tablet market. Any defensible formulation position is therefore more likely to arise from the oral suspension composition, manufacturing process, packaging, device, or method of use than from the active ingredient.

The relevant intellectual-property categories are:

IP category	Potential scope
Composition patents	Specific excipient combinations, concentrations, pH ranges, or viscosity profiles
Suspension patents	Redispersibility, sedimentation control, and dose uniformity
Stability patents	Chemical or microbiological stability during storage and in-use periods
Flavor patents	Specific sweetener-flavor systems or taste-masking combinations
Device patents	Bottle adapters, syringes, dosing interfaces, or packaging
Manufacturing patents	Mixing sequence, homogenization, deaeration, or filling process
Method-of-use patents	Liquid amlodipine administration for defined patient populations

The FDA label and public regulatory record establish the approved formulation and use, but they do not alone determine the full private patent position. Patent claims must be assessed by jurisdiction, claim status, terminal disclaimers, maintenance fees, and any Orange Book listing.

What is the Orange Book and regulatory status of Katerzia?

Katerzia is an FDA-approved prescription drug marketed as an oral suspension of amlodipine besylate. Its 505(b)(2) approval allowed the sponsor to rely on existing information for amlodipine while providing product-specific data for the suspension formulation and proposed use.[1]

The relevant regulatory considerations are:

Regulatory issue	Katerzia assessment
FDA approval	Approved
NDA type	505(b)(2)
Active ingredient exclusivity	No new-chemical-entity exclusivity expected because amlodipine is established
Clinical-investigation exclusivity	Potentially applicable to product-specific investigations, subject to FDA listing and expiry
Orange Book role	Relevant for listed patents and exclusivity
Generic pathway	Depends on FDA classification, reference-product status, and product-specific requirements
Biosimilar pathway	Not applicable; Katerzia is a small-molecule drug
Paragraph IV risk	Possible if a listed patent blocks an ANDA or 505(b)(2) application

Amlodipine has no biosimilar risk because biosimilars apply to biological products. The competitive threat is generic or follow-on oral suspension entry.

When does Katerzia lose exclusivity?

Katerzia’s market protection is likely to depend on three separate concepts:

1. Regulatory exclusivity associated with the 505(b)(2) approval.
2. Any formulation or device patents listed for the product.
3. Commercial advantages created by pediatric usability, prescriber familiarity, and distribution.

A three-year period of exclusivity may apply where FDA determined that the NDA relied on new clinical investigations essential to approval. That period does not provide the same protection as five-year new chemical entity exclusivity and generally does not block all competing products outside the protected approval conditions. Product-specific patent expiry dates must be confirmed from the current Orange Book and the relevant patent records before making a launch forecast.[2]

A generic applicant could challenge listed patents through a Paragraph IV certification. The commercial timing would then depend on patent litigation, a 30-month stay if statutory conditions are met, settlement terms, and the applicant’s ability to obtain final approval.

What generic entry risks exist for Katerzia?

The primary generic-entry risk is a lower-cost amlodipine oral suspension that matches the reference product’s concentration and provides acceptable pharmaceutical equivalence and bioequivalence.

Potential entry routes include:

ANDA entry

An ANDA applicant would seek approval based on the reference listed drug and would need to satisfy FDA requirements for dosage form, strength, quality, stability, labeling, and bioequivalence. Suspensions present additional technical challenges compared with tablets because the applicant must control particle size, sedimentation, redispersion, viscosity, and dose uniformity.

505(b)(2) entry

A sponsor could pursue a separate oral liquid with a different formulation, flavor, concentration, device, or patient population. This route may be useful where the product is not sufficiently identical to the reference product for an ANDA or where the sponsor wants formulation-specific claims.

Compounding substitution

Compounded amlodipine liquids may compete in hospitals, specialty pharmacies, and pediatric practices. Compounded products can be less expensive and may offer customized concentrations, but they usually have less standardized stability, packaging, flavor, and commercial distribution than an FDA-approved product.

How strong is Katerzia’s patent estate?

The formulation patent estate is potentially stronger than the active-ingredient estate because amlodipine is an old, heavily genericized molecule. The strength of any Katerzia patent position depends on claim specificity and the availability of design-around options.

A strong formulation patent would ideally claim a narrow combination that produces measurable advantages, such as:

• Improved redispersibility after defined storage conditions
• Reduced dose variability between the first and last doses
• Improved chemical stability
• Longer in-use stability
• Defined viscosity and syringe-force parameters
• Preservative efficacy at reduced preservative concentration
• Superior palatability supported by controlled studies

Weak claims would cover broad classes of conventional excipients without a demonstrated technical effect. Generic developers can often avoid broad composition claims by changing polymer ratios, buffer concentrations, flavor systems, preservatives, or packaging.

The strongest commercial barrier may therefore be a layered estate covering composition, process, packaging, and device rather than a single excipient patent.

Which companies could challenge Katerzia?

Potential competitors include:

• Large generic manufacturers with pediatric liquid capabilities
• Specialty generic companies focused on oral liquids
• Contract development and manufacturing organizations
• Hospital-compounding networks
• Branded pediatric formulation companies
• Companies developing liquid antihypertensive portfolios

The most credible challengers are manufacturers already operating liquid dosage-form plants with validated suspension processes and pediatric oral-syringe packaging. Tablet-focused generic manufacturers would have to add capabilities for microbiological control, suspension homogeneity, bottle filling, shake-labeling, and in-use stability.

What licensing and partnership opportunities exist?

Katerzia’s excipient and delivery platform could support licensing in four areas:

Regional commercialization

A partner with pediatric and specialty-pharmacy coverage could commercialize the product outside the sponsor’s strongest markets. The liquid format may have greater value in countries where pediatric hypertension treatment relies on hospital pharmacies or where tablet swallowing is a significant barrier.

Pediatric liquid platform licensing

The formulation technology could be adapted to other calcium-channel blockers or cardiovascular drugs. The most valuable platform attributes would be a scalable suspending system, reliable taste masking, and a common bottle-and-syringe presentation.

Hospital and specialty-pharmacy supply

Institutional contracts could use Katerzia or a follow-on formulation to reduce pharmacy compounding. The economic case depends on labor savings, reduced preparation errors, shelf-life, and procurement price.

Device licensing

A dose-delivery system optimized for low-volume pediatric suspensions could be licensed independently or bundled with a drug product. Device ownership may provide a separate barrier to substitution.

How does Katerzia compare with competing amlodipine formulations?

Product type	Main advantage	Main weakness	Commercial position
Katerzia suspension	Ready-to-use FDA-approved liquid	Higher price than tablets; excipient and taste constraints	Branded pediatric and swallowing-impaired segment
Amlodipine tablets	Low cost and broad availability	Difficult for some patients to swallow or titrate	Dominant adult generic market
Extemporaneous compounded liquid	Flexible concentration and flavor	Variable stability, quality, and availability	Institutional and individualized use
Future generic suspension	Potentially lower price with ready-to-use dosing	Must overcome formulation and regulatory barriers	Direct Katerzia competitor
Alternative 505(b)(2) liquid	Opportunity for differentiated concentration, flavor, or device	Development and approval costs	Lifecycle and specialty-market opportunity

What is the revenue exposure from Katerzia substitution?

The exposure is concentrated in the liquid-dosing segment rather than the total amlodipine market. Generic tablet substitution does not fully solve the administration needs of children and adults with dysphagia. Katerzia can retain value if it demonstrates lower caregiver burden, better adherence, reliable dose delivery, and reduced use of compounded products.

Revenue pressure would be greatest if a competitor offers:

• The same 1 mg/mL concentration
• A comparable or better flavor
• Equal or longer in-use stability
• A lower price
• A familiar oral syringe
• Broad retail and specialty-pharmacy distribution

A lower-priced generic suspension could expand the total liquid market by converting patients from compounded products while reducing the branded product’s price and share. The net market effect would depend on payer coverage and the spread between branded and generic acquisition costs.

What manufacturing and IP barriers affect follow-on products?

Manufacturing barriers include maintaining uniform particle distribution, controlling microbial burden, preventing foaming, minimizing air entrapment, and achieving consistent fill weights. The process must remain robust across commercial batch sizes.

Critical development studies include:

• Particle-size characterization
• Sedimentation and redispersion testing
• Dose uniformity through the full bottle
• Viscosity and syringe-delivery testing
• Preservative effectiveness
• Forced-degradation studies
• Container-closure compatibility
• Extractables and leachables
• Freeze-thaw and temperature-cycle stability
• In-use stability after opening

The principal IP barrier is likely claim differentiation. A follow-on manufacturer can often avoid a formulation claim by using a different preservative, flavor, polymer ratio, buffer, or package. Process patents become more important when the composition is difficult to reproduce without a defined mixing or homogenization sequence.

Key Takeaways

• Katerzia is a 1 mg/mL FDA-approved amlodipine oral suspension for patients who need liquid dosing.
• Its excipient strategy centers on suspension structure, pH control, preservation, sweetening, flavor, and syringe compatibility.
• Amlodipine itself provides little meaningful composition-of-matter protection because it is an established generic molecule.
• The most valuable IP is likely to cover excipient combinations, stability, redispersibility, manufacturing, packaging, and dosing devices.
• Generic suspension entry is technically more difficult than generic tablet entry but remains commercially plausible.
• Preservative-free packaging, alternative flavors, improved syringes, and hospital-oriented presentations are the clearest lifecycle opportunities.
• Katerzia has no biosimilar risk. Its competitive risks are generic oral suspensions, 505(b)(2) liquids, compounded products, and tablet substitution.
• Exact patent expiry and Paragraph IV exposure require confirmation against the current Orange Book and live patent records.

FAQs

Can Katerzia be replaced with amlodipine tablets?

Amlodipine tablets contain the same active moiety but are not always practical substitutes for patients who cannot swallow tablets or require liquid administration. Substitution should follow the prescriber’s dosing instructions.

Is Katerzia an extended-release amlodipine product?

No. Katerzia is an immediate-release oral suspension. Its differentiation is the liquid dosage form, not modified release.

Could a preservative-free amlodipine suspension compete with Katerzia?

Yes. A preservative-free product could target pediatric, hospital, and specialty-pharmacy segments, but it would require an effective multidose packaging and microbiological-control strategy.

Does a different flavor avoid Katerzia formulation patents?

Not necessarily. A flavor change may avoid some composition claims, but broader claims could cover the suspending system, buffer, preservative, manufacturing process, or device.

Are compounded amlodipine liquids a major commercial threat?

They can compete in localized settings, particularly hospitals and specialty pharmacies. Their disadvantages are variable availability, shorter or less predictable stability, and the absence of the standardized manufacturing and labeling associated with an FDA-approved product.

References

1. U.S. Food and Drug Administration. (2021). Katerzia (amlodipine besylate) oral suspension: Prescribing information. Azurity Pharmaceuticals.

2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. FDA, Center for Drug Evaluation and Research.

3. U.S. Food and Drug Administration. (2024). Drugs@FDA: Katerzia, NDA 214439. Center for Drug Evaluation and Research.

4. U.S. Food and Drug Administration. (2019). ANDA submissions: Content and format of an abbreviated new drug application. Center for Drug Evaluation and Research.

5. U.S. Food and Drug Administration. (2016). Waiver of in vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms based on a biopharmaceutics classification system. Center for Drug Evaluation and Research.