List of Excipients in Branded Drug QUETIAPINE

Generic Drugs Containing QUETIAPINE

Company	Ingredient	NDC	Excipient
Teva Pharmaceuticals USA Inc	quetiapine	0093-2063	CELLULOSE, MICROCRYSTALLINE
Teva Pharmaceuticals USA Inc	quetiapine	0093-2063	DIBASIC CALCIUM PHOSPHATE DIHYDRATE
Teva Pharmaceuticals USA Inc	quetiapine	0093-2063	FD&C YELLOW NO. 6
Teva Pharmaceuticals USA Inc	quetiapine	0093-2063	FERRIC OXIDE YELLOW

What are the Most Frequently-Used Excipients in QUETIAPINE?

# Of NDCs	Excipient
75	CELLULOSE, MICROCRYSTALLINE
48	DIBASIC CALCIUM PHOSPHATE DIHYDRATE
4	ETHYLCELLULOSE
3	FD&C YELLOW NO. 6

Quetiapine Excipient Strategy and Commercial Opportunities

Last updated: August 16, 2026

Quetiapine is a mature, genericized atypical antipsychotic with limited active-ingredient patent protection and substantial formulation opportunity. The strongest commercial positions are in extended-release delivery, orally disintegrating or sprinkle products, taste masking, dose flexibility, adherence support, and differentiated excipient systems that improve manufacturability or reduce food-effect variability.

Quetiapine fumarate is marketed primarily as immediate-release tablets and extended-release tablets. The reference products are Seroquel and Seroquel XR, originally developed by AstraZeneca. FDA-approved generics are widely available for both dosage forms. Biosimilar risk is not relevant because quetiapine is a chemically synthesized small molecule rather than a biologic.[1][2]

What is the commercial status of quetiapine?

Quetiapine is approved for schizophrenia and bipolar disorder, including manic episodes and depressive episodes, and as adjunctive therapy for major depressive disorder in selected patients. The immediate-release product is generally administered two or three times daily depending on the indication. Seroquel XR is administered once daily.[1][2]

Product	Active ingredient	Dosage form	Commercial position
Seroquel	Quetiapine fumarate	Immediate-release tablet	Reference product; generic competition established
Seroquel XR	Quetiapine fumarate	Extended-release tablet	Reference product; generic competition established
Generic quetiapine	Quetiapine fumarate	Immediate-release tablet	Broad generic supply
Generic quetiapine ER	Quetiapine fumarate	Extended-release tablet	Multiple approved or marketed competitors

Quetiapine is a high-volume, low-cost generic active pharmaceutical ingredient. Value is concentrated in manufacturing scale, hospital and institutional supply contracts, controlled-release technology, differentiated dosage forms, and regulatory execution rather than in the molecule itself.

What patents protect quetiapine and Seroquel?

The original quetiapine compound and pharmaceutical composition patents have expired. The main commercial patent barrier was the original Seroquel patent estate, which supported protection for quetiapine fumarate and related pharmaceutical compositions. Immediate-release generic entry began after expiration and patent litigation involving Paragraph IV certifications.

Seroquel XR relied on later controlled-release formulation protection. The key extended-release patent period ended in the mid-2010s, with generic competition entering after settlement and regulatory developments. The practical result is that quetiapine XR is no longer protected by a commercially meaningful composition-of-matter monopoly in the United States.

What is the Orange Book status of quetiapine?

FDA Orange Book listings historically identified patents associated with Seroquel and Seroquel XR, including patents covering the active ingredient and extended-release formulations. Current commercial analysis should distinguish:

1. Expired active-ingredient patents.
2. Expired or commercially exhausted formulation patents.
3. Any remaining listed patents applicable to specific reference products.
4. Regulatory exclusivity, which is separate from patent term.

For generic applicants, the relevant pathway is an ANDA supported by bioequivalence to the listed reference drug. A Paragraph IV certification can challenge an unexpired listed patent, but the commercial importance of such challenges is now limited because the principal quetiapine patent barriers have expired.[3]

When did quetiapine lose exclusivity?

Quetiapine lost effective exclusivity in stages rather than on a single date.

Exclusivity layer	Approximate status	Commercial effect
Original quetiapine compound protection	Expired in the 2000s	Enabled immediate-release generic entry
Seroquel immediate-release market protection	Expired by the late 2000s	Broad generic substitution
Seroquel XR formulation protection	Expired or became commercially ineffective in the mid-to-late 2010s	Generic ER competition
Regulatory exclusivity	Expired for the principal indications	No meaningful current barrier
Formulation and device opportunities	Potentially available for new products	Requires separate patenting and FDA support

The remaining opportunity is therefore not classic lifecycle management based on the original molecule. It is product differentiation through excipient selection, release control, dosage-form engineering, manufacturing economics, and patient-use advantages.

What excipients are used in quetiapine tablets?

Quetiapine products use conventional tablet excipients. The exact composition varies by manufacturer, strength, dosage form, coating system, and manufacturing process.

Typical immediate-release excipient categories include:

• Lactose or another diluent
• Microcrystalline cellulose
• Povidone or copovidone as a binder
• Sodium starch glycolate or crospovidone as a disintegrant
• Magnesium stearate as a lubricant
• Colloidal silicon dioxide as a glidant
• Film-coating polymers, plasticizers, pigments, and opacifiers

Extended-release formulations use a different excipient architecture. Common technologies include hydrophilic matrix polymers such as hypromellose, hydrophobic release modifiers, polymeric coatings, and combinations of high- and low-viscosity grades.

The FDA Inactive Ingredient Database is the principal regulatory reference for determining prior use of excipients in approved drug products and dosage forms.[4] A formulation developer must evaluate the maximum daily exposure, route, dosage form, inactive-ingredient precedent, and proposed concentration.

Which excipients are most commercially relevant?

Excipient class	Function in quetiapine	Commercial opportunity
Hypromellose	Controls hydration and drug release	XR matrix optimization
Polyvinylpyrrolidone	Granulation binder and precipitation control	Process robustness
Crospovidone	Rapid tablet disintegration	IR and ODT development
Sodium starch glycolate	Swelling disintegrant	Low-cost IR performance
Microcrystalline cellulose	Diluent and compression aid	High-speed tableting
Mannitol	Diluent, mouthfeel, cooling effect	ODT and pediatric formats
Copovidone	Binder and film former	Direct compression and coating
Ethylcellulose	Hydrophobic release barrier	Multi-particulate or coated systems
Methacrylate polymers	pH-dependent or sustained release	Enteric and delayed-release concepts
Sweeteners and flavors	Taste masking	ODT, liquid, and sprinkle products
Lipid excipients	Solubility and release modification	Suspension and multiparticulate systems

What formulation patents could protect quetiapine products?

New protection is more likely to arise from a defined formulation, process, or use than from quetiapine itself. Patentable claim areas include:

Extended-release matrix systems

A developer could claim a specific polymer ratio, tablet hardness, dissolution profile, manufacturing process, or release behavior across fed and fasted conditions. Broad claims to generic sustained-release quetiapine are likely to face prior-art pressure, but narrow claims covering a reproducible dissolution profile or manufacturing method may retain value.

Multiparticulate and sprinkle formulations

A capsule or sachet containing coated quetiapine pellets could support administration to patients with swallowing difficulty. Protection may cover:

• Pellet size distribution
• Polymer coating thickness
• Drug layering process
• Food compatibility
• Stability after opening
• Dose titration by pellet count or weight

This format has commercial relevance in psychiatric populations where swallowing difficulty, institutional administration, or adherence problems limit tablet use.

Orally disintegrating tablets

ODT products can target patients who resist tablets, have dysphagia, or require supervised administration. Patentable features may include:

• Fast disintegration
• Low friability
• Taste masking
• Low-dose uniformity
• Co-processed excipient systems
• Manufacturing by direct compression or freeze-drying

Quetiapine has a strong bitter taste profile, making taste masking a central technical problem. Ion-exchange resins, polymeric coatings, cyclodextrins, lipid barriers, and flavor systems are possible approaches, but each must preserve rapid drug release after swallowing.

Liquid and suspension products

An oral suspension or ready-to-use liquid could address pediatric, geriatric, psychiatric-care, or tube-feeding use cases. Critical technical issues include sedimentation, redispersibility, chemical stability, microbial control, dose uniformity, and adsorption to administration equipment.

A liquid product may face a higher regulatory burden than a conventional tablet. It could also create a more defensible formulation estate if the product solves a specific stability or administration problem.

How should excipients be selected for immediate-release quetiapine?

Immediate-release quetiapine is a cost-sensitive product. The preferred formulation should use common, globally available excipients and a robust process with minimal sensitivity to raw-material variability.

A conventional development strategy is:

1. Select a diluent system that supports dose uniformity across strengths.
2. Use a binder that produces strong granules without slowing disintegration.
3. Screen superdisintegrants for rapid release at high tablet hardness.
4. Optimize magnesium stearate concentration and blending time to avoid dissolution slowdown.
5. Control particle-size distribution and segregation during compression.
6. Establish dissolution similarity against the reference product.
7. Confirm stability under high humidity because moisture can alter tablet hardness and disintegration.

For low-cost generic products, the best commercial excipient strategy is often a manufacturing advantage rather than a novel ingredient. Direct compression, continuous manufacturing, reduced coating weight, and fewer processing steps can improve gross margin without creating regulatory complexity.

How should excipients be selected for quetiapine extended-release products?

Extended-release quetiapine presents a more valuable technical opportunity because release performance is central to product quality and clinical dosing.

A matrix formulation must control:

• Initial drug release
• Matrix hydration
• Polymer erosion
• Dose dumping risk
• Fed-versus-fasted performance
• Release across the gastrointestinal tract
• Strength proportionality
• Tablet size and swallowability

Hydrophilic matrices based on hypromellose are practical, scalable, and well established. A higher-viscosity polymer can reduce release rates but may increase tablet size or create sensitivity to compression force. A lower-viscosity polymer can improve manufacturability but may produce excessive early release.

Hydrophobic polymers and coated multiparticulates may offer greater control but add process steps, solvent or coating risks, and scale-up complexity. The commercial choice depends on whether the product is intended as a low-cost ANDA or a differentiated 505(b)(2) product.

What FDA regulatory pathways apply to new quetiapine formulations?

ANDA pathway

An ANDA is appropriate when the proposed product is therapeutically equivalent to a reference listed drug. The applicant must demonstrate pharmaceutical equivalence and bioequivalence. Excipient changes are acceptable if the final product meets the applicable quality and bioequivalence requirements.[5]

An ANDA strategy is commercially attractive for standard immediate-release tablets and conventional ER tablets, but it limits product differentiation and pricing.

505(b)(2) pathway

A 505(b)(2) application may be appropriate for a new dosage form, route, strength, formulation, or delivery system that relies partly on published literature or FDA findings for an approved product. Potential targets include:

• Oral suspension
• ODT
• Sprinkle capsule
• Modified-release formulation with a differentiated profile
• New administration method for patients unable to swallow tablets

A 505(b)(2) product can obtain its own formulation and method-of-use patents, although it remains exposed to generic substitution and patent challenges after approval.[6]

New chemical entity pathway

A new chemical entity pathway is not applicable to ordinary quetiapine fumarate reformulation. The molecule is established, and any value must come from the product design, not new active-ingredient status.

What commercial opportunities exist for quetiapine excipient suppliers?

Excipient companies can pursue both direct formulation partnerships and platform licensing.

Modified-release polymer systems

Suppliers of hypromellose, ethylcellulose, methacrylate polymers, and co-processed matrix systems can offer formulation development packages that include:

• Excipient grade selection
• Dissolution modeling
• Fed-state risk assessment
• Scale-up support
• Regulatory documentation
• Design-space development

The strongest opportunity is a reproducible ER platform that reduces bioequivalence failures.

Taste-masking systems

Taste masking is relevant to ODT, liquid, and sprinkle products. Commercial systems may combine ion exchange, polymer coating, lipid barriers, and flavor correction. The supplier’s defensibility improves when the system provides both taste suppression and rapid post-swallow release.

Co-processed excipients

Co-processed excipients can improve flow, compactibility, tablet strength, and disintegration. They are attractive for high-speed production and lower tooling pressure. A platform that allows direct compression of quetiapine across multiple strengths could reduce manufacturing cost and simplify site transfer.

Pediatric and geriatric dosage forms

Quetiapine is used in patient populations where swallowing and administration challenges are common. A liquid, ODT, or sprinkle system could support institutional, home-care, and specialty-pharmacy channels. Commercial value depends on clinical positioning, dosing flexibility, stability, and payer acceptance.

How strong is the quetiapine formulation patent estate?

The legacy estate is weak for the original molecule and stronger only where a specific delivery system remains technically distinct.

Patent area	Strength assessment	Reason
Quetiapine compound	Low	Expired composition protection
Conventional IR tablet	Low	Mature technology and extensive prior art
Conventional hydrophilic ER tablet	Moderate to low	Prior art is extensive; narrow claims may survive
Taste-masked ODT	Moderate	Combination of taste, disintegration, and release claims
Sprinkle multiparticulates	Moderate	Process and coating parameters can be product-specific
Oral suspension	Moderate	Stability and dosing claims may differentiate
Manufacturing process	Moderate	Stronger if it reduces impurities, variability, or cost
Device-linked administration	Variable	Depends on the device and use claims

The most defensible estate would combine formulation claims, process claims, dissolution specifications, stability data, and method-of-use claims. A single broad excipient claim is unlikely to provide durable protection in a mature small-molecule market.

Which companies compete in quetiapine?

Competition includes large generic manufacturers, specialty generic companies, contract development and manufacturing organizations, API suppliers, and excipient vendors. The principal competitive advantages are:

• Reliable quetiapine fumarate API supply
• Low-cost tablet production
• Strong ANDA portfolio management
• Ability to support multiple strengths
• Hospital and institutional contracting
• Controlled-release formulation capability
• Global registration and manufacturing coverage

Excipient suppliers should target manufacturers developing differentiated dosage forms rather than competing only for standard IR tablet volume. The premium opportunity lies in formulation support, regulatory packages, and manufacturing transfer rather than commodity excipient sales.

What generic launch risks exist for quetiapine?

Generic launch risk is lower for standard immediate-release tablets because the product is mature and widely manufactured. Risks remain in several areas:

• Bioequivalence failure for extended-release products
• Food-effect differences
• Dissolution mismatch
• Strength proportionality problems
• Tablet size and mechanical-strength tradeoffs
• Stability failures under humidity
• Taste-masking failure in ODT or liquid formats
• Inactive-ingredient exposure limits
• API impurity or polymorph control
• Manufacturing-site transfer delays

For ER products, a formulation that passes dissolution testing may still fail in vivo if the release profile changes under fed conditions. Excipient grade and supplier consistency therefore have direct commercial significance.

What licensing opportunities exist for quetiapine formulations?

Licensing opportunities are most credible in three categories:

1. Proprietary modified-release platforms that can support an ANDA or 505(b)(2) program.
2. Taste-masking and fast-disintegrating systems for ODT or sprinkle products.
3. Stable liquid or multiparticulate delivery systems for dysphagia and supervised administration.

A licensing agreement may include an upfront payment, development milestones, manufacturing rights, territory-specific commercialization rights, and supply commitments. Platform owners should avoid relying solely on broad composition claims. The strongest package combines patent protection with demonstrated bioequivalence, scalable manufacturing, and a defined clinical-use advantage.

Key Takeaways

• Quetiapine’s original active-ingredient exclusivity has expired, and conventional tablets are heavily genericized.
• The main commercial opportunity is formulation differentiation, not molecule ownership.
• Extended-release, ODT, sprinkle, liquid, and taste-masked products offer the clearest excipient-led opportunities.
• Hypromellose, ethylcellulose, methacrylate polymers, crospovidone, mannitol, co-processed excipients, and taste-masking systems are commercially relevant.
• ANDA products offer lower regulatory risk but limited pricing power.
• 505(b)(2) products may support stronger differentiation but require more clinical, regulatory, and commercial investment.
• Formulation patents should be supported by process, dissolution, stability, and administration claims.
• No biosimilar pathway applies to quetiapine.
• The highest-value excipient strategy is one that improves bioequivalence probability, manufacturing economics, patient administration, or release control.

FAQs

Can a new excipient extend quetiapine market exclusivity?

A new excipient alone does not restore exclusivity for quetiapine. It can support patent protection for a specific formulation if the product has a novel, non-obvious, and adequately described technical configuration.

Is quetiapine suitable for an orally disintegrating tablet?

Yes. Quetiapine is a candidate for ODT development, but its bitter taste and dose size require effective taste masking, rapid disintegration, acceptable tablet strength, and preservation of dissolution performance.

Can quetiapine be developed as a liquid for pediatric use?

Yes. A liquid or suspension could address dosing flexibility and swallowing limitations. The principal development issues are chemical stability, sedimentation, redispersibility, microbial control, and dose uniformity.

What is the best excipient strategy for quetiapine XR?

A robust hydrophilic matrix using a carefully selected hypromellose grade is a practical starting point. The formulation must be optimized for dissolution, food effect, tablet size, compression behavior, and in vivo release.

Are quetiapine excipient patents likely to block generic entry?

Broad excipient patents are unlikely to block standard generic quetiapine entry. Narrow patents covering a particular ER matrix, taste-masking architecture, multiparticulate coating, or administration method could affect specific differentiated products.

References

1. U.S. Food and Drug Administration. (2013). Seroquel prescribing information. AstraZeneca Pharmaceuticals LP.

2. U.S. Food and Drug Administration. (2013). Seroquel XR prescribing information. AstraZeneca Pharmaceuticals LP.

3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov

4. U.S. Food and Drug Administration. (2024). Inactive Ingredient Database. https://www.accessdata.fda.gov/scripts/cder/iig/index.cfm

5. U.S. Food and Drug Administration. (2024). ANDA submissions: Content and format. https://www.fda.gov

6. U.S. Food and Drug Administration. (2024). Applications covered by Section 505(b)(2). https://www.fda.gov