List of Excipients in Branded Drug ALREX

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
STAT Rx USA LLC	ALREX	loteprednol etabonate	16590-007	BENZALKONIUM CHLORIDE
STAT Rx USA LLC	ALREX	loteprednol etabonate	16590-007	EDETATE DISODIUM
STAT Rx USA LLC	ALREX	loteprednol etabonate	16590-007	GLYCERIN

ALREX Excipient Strategy and Commercial Opportunities

Last updated: August 7, 2026

ALREX is a 0.2% loteprednol etabonate ophthalmic suspension for short-term treatment of seasonal allergic conjunctivitis. Its commercial opportunity is concentrated in formulation engineering rather than new active-ingredient exclusivity. The most attractive strategies are preservative-free delivery, improved suspension uniformity, reduced ocular discomfort, longer in-use stability, and manufacturing platforms that support generic or differentiated ophthalmic products.

What is ALREX and how does its formulation work?

ALREX contains loteprednol etabonate at 2 mg/mL in a topical ophthalmic suspension. The product is administered as one drop into the affected eye four times daily, with treatment generally limited to the allergic-conjunctivitis episode specified in the prescribing information [1].

Loteprednol etabonate is an ester corticosteroid. Its physicochemical properties require a dispersed-particle suspension rather than a simple aqueous solution. The formulation must keep drug particles uniformly distributed, allow rapid redispersion after shaking, deliver a reproducible dose through the dropper tip, and limit local irritation.

The label instructs patients to shake the bottle well before use. That instruction reflects the central formulation risk: dose uniformity can decline if the drug settles or aggregates during storage or in-use handling [1].

ALREX formulation profile

Attribute	ALREX profile
Active ingredient	Loteprednol etabonate
Strength	0.2%, equivalent to 2 mg/mL
Dosage form	Ophthalmic suspension
Route	Topical ocular
Primary indication	Seasonal allergic conjunctivitis
Administration	One drop in the affected eye four times daily
Container	Multidose ophthalmic bottle
Key physical requirement	Redispersible suspension with consistent delivered dose
Prescribing status	FDA-approved prescription ophthalmic corticosteroid
Manufacturer	Bausch + Lomb

What excipients are used in ALREX?

ALREX uses a conventional suspension vehicle containing wetting, viscosity-modifying, tonicity-adjusting, buffering, and chelating components. The FDA label identifies the following inactive ingredients: boric acid, edetate disodium, glycerin, povidone, purified water, sodium chloride, sodium hydroxide, and tyloxapol [1].

The label does not provide the quantitative concentration of each excipient. That limits direct cost and formulation benchmarking but does not prevent functional analysis.

Excipient	Probable formulation role	Commercial relevance
Tyloxapol	Nonionic surfactant and wetting agent	Supports particle wetting and suspension uniformity
Povidone	Suspending and viscosity-modifying polymer	May improve redispersion and dose consistency
Glycerin	Humectant and tonicity contributor	Helps control osmotic pressure and ocular comfort
Sodium chloride	Tonicity adjustment	Supports compatibility with the ocular surface
Boric acid	Buffering and tonicity contribution	Helps maintain pH and product stability
Edetate disodium	Chelating agent	Binds trace metals that can accelerate degradation
Sodium hydroxide	pH adjustment	Sets final formulation pH
Purified water	Aqueous vehicle	Main continuous phase

The excipient system is commercially important because ophthalmic suspensions have narrow operating windows. Increasing surfactant concentration can improve wetting but may increase irritation or foaming. Increasing polymer concentration can slow sedimentation but may impair drop formation, spreadability, or patient comfort. Tonicity and pH adjustments can improve tolerability but also affect chemical stability and preservative performance.

Which ALREX excipients create the strongest formulation advantages?

Tyloxapol and particle wetting

Tyloxapol is a key differentiating component because poorly wetted loteprednol etabonate particles can float, agglomerate, settle rapidly, or form hard sediment. A wetting agent lowers interfacial tension between the hydrophobic drug and the aqueous vehicle.

A follow-on product could test alternative nonionic surfactants, surfactant combinations, or surface-treated drug particles. The development target would be consistent redispersion with lower ocular irritation and no adverse impact on preservative effectiveness.

Potential substitutes include polysorbates, poloxamers, polyoxyl castor oils, and other ophthalmically acceptable wetting agents. Substitution would require compatibility testing, extractables and leachables review, ocular tolerance studies, and comparative performance testing.

Povidone and suspension rheology

Povidone can increase vehicle viscosity and improve particle suspension. The commercial challenge is balancing sedimentation control against patient usability. A vehicle that is too viscous may produce a larger or slower-forming drop, blur vision, or leave a noticeable residue.

A competitor can pursue a narrow-viscosity formulation that improves dose uniformity without converting the product into a gel. This strategy could support a differentiated product claim based on reduced shaking dependence, improved delivery consistency, or a lower frequency of bottle inversion.

Glycerin, sodium chloride, and ocular comfort

Glycerin and sodium chloride contribute to tonicity. Ocular comfort is commercially relevant in allergic conjunctivitis because the underlying condition already produces burning, itching, tearing, and inflammation.

A reformulated product could optimize tonicity rather than merely reproduce the reference formulation. The relevant development endpoints would include drop comfort, transient stinging, redness, tear-film disruption, and patient preference.

Edetate disodium and metal control

Edetate disodium is a low-cost excipient with potential stability value. Trace metals can catalyze oxidation or interact with packaging components. The chelator can support chemical stability, but its concentration must be controlled because chelation can affect preservative systems and container compatibility.

Buffer and pH design

Boric acid and sodium hydroxide support pH control. A pH shift can change loteprednol etabonate stability, particle surface properties, preservative performance, and patient comfort.

A next-generation product could use a different ophthalmically acceptable buffer system, but the regulatory burden would include degradation profiling, container-closure studies, and ocular tolerability work. Buffer changes are more commercially meaningful when paired with a clear performance improvement, such as lower stinging or better stability under temperature excursions.

What formulation patents could protect an ALREX follow-on product?

Formulation patents are more likely to protect a differentiated ALREX follow-on than broad composition-of-matter claims. Relevant claim categories include:

1. A loteprednol etabonate ophthalmic suspension with a defined particle-size distribution.
2. A suspension with specified viscosity, sedimentation rate, or redispersibility.
3. A preservative-free multidose formulation.
4. A unit-dose formulation with defined drug concentration and excipient ratios.
5. A formulation with a selected surfactant, polymer, or buffer system.
6. A product with improved dose uniformity after defined storage or handling conditions.
7. A manufacturing process involving micronization, wet milling, homogenization, or controlled crystallization.
8. A container-closure system that improves sterility, stability, or in-use life.
9. A method of treating allergic conjunctivitis using a specific dosing schedule or delivery system.

A patent strategy should combine composition claims with process and container claims. A composition patent can be vulnerable to excipient substitution. A manufacturing patent can be avoided through a different particle-engineering route. A packaging patent can be bypassed with another container system. Layered claims reduce design-around exposure.

When does ALREX lose exclusivity?

ALREX's principal commercial protection is no longer expected to come from an unexpired original composition patent. Loteprednol etabonate was approved decades ago, and the relevant small-molecule exclusivity period has elapsed. The commercial question is therefore generic substitution, current Orange Book listings, and the status of any later-issued formulation or method-of-use rights.

The FDA approved ALREX under NDA 21-062 for seasonal allergic conjunctivitis [1]. FDA Orange Book analysis should focus on:

• Active patent listings for NDA 21-062.
• Any listed formulation or method-of-use patents.
• Paragraph IV certifications filed against listed patents.
• Thirty-month stays or district-court litigation.
• Approved ANDAs for loteprednol etabonate ophthalmic suspension 0.2%.
• The current therapeutic-equivalence code assigned to each approved product [2].

A product-level patent expiration date should not be inferred solely from the original ALREX approval date. Listed patents, pediatric exclusivity, patent-term adjustments, and later-approved formulations can produce different dates.

What is the Orange Book status of ALREX?

The relevant Orange Book product is the loteprednol etabonate ophthalmic suspension 0.2% approved under NDA 21-062. Orange Book status determines whether an ANDA applicant must address listed patents and whether a generic applicant can rely on the reference product for approval [2].

For an ANDA applicant, the main regulatory paths are:

Certification	Meaning for ALREX competition
Paragraph I	No patent information is listed
Paragraph II	Listed patent has expired
Paragraph III	Applicant will wait for patent expiration
Paragraph IV	Applicant alleges the listed patent is invalid, unenforceable, or not infringed

A Paragraph IV filing can create litigation risk, but litigation is commercially material only if an unexpired patent is listed and the reference sponsor sues within the statutory period. A formulation patent with narrow excipient or particle-size claims may be easier to challenge than a strong composition patent, but its practical value depends on the scope of the listed claims and the design of the proposed generic.

What generic entry risks exist for ALREX?

The generic-development barrier is technical rather than based solely on active-ingredient synthesis. A successful product must match or closely reproduce several performance attributes:

• Drug particle size and morphology.
• Sedimentation and redispersibility.
• Delivered dose per drop.
• Drop size and bottle performance.
• pH and osmolality.
• Chemical and physical stability.
• Microbial quality.
• Sterility assurance.
• Preservative effectiveness, if a preservative is used.
• Comparative ocular tolerability.

FDA ophthalmic product guidance emphasizes product quality attributes that are especially important for suspensions, including particle size, uniformity, sterility, and container-closure performance [3].

The generic applicant may not need to duplicate every excipient if the product satisfies FDA requirements for pharmaceutical equivalence, bioequivalence, safety, and quality. Excipients can differ when the differences do not create an unacceptable safety or performance risk. For this reason, the ALREX excipient list is a development reference, not necessarily a mandatory formulation blueprint.

What preservative-free opportunities exist for ALREX?

A preservative-free ALREX alternative is the clearest excipient-led commercial opportunity. Multidose ophthalmic products typically require a preservative or a container system that maintains sterility throughout the in-use period. Preservatives can contribute to ocular-surface irritation, particularly in patients with frequent dosing or pre-existing surface disease.

Three product architectures are commercially relevant:

Preservative-free unit-dose suspension

Single-use vials remove the need for a conventional multidose preservative system. The tradeoffs are higher packaging cost, more material use, greater shipping volume, and patient inconvenience.

Preservative-free multidose bottle

One-way valves, filter systems, or nonreturn mechanisms can maintain microbiological quality without adding a preservative. These systems may support premium pricing, but they introduce device-development and manufacturing complexity.

Low-preservative multidose formulation

A lower preservative load can reduce tolerability concerns while retaining a conventional bottle. This approach may offer a lower-cost bridge between legacy ALREX and a fully preservative-free product.

The strongest product opportunity is likely a preservative-free or low-irritation product with evidence of improved patient comfort, not a simple excipient substitution without a clinically visible benefit.

How can manufacturers use ALREX excipients in a commercial platform?

A company could use the ALREX formulation as a technical platform for multiple ophthalmic corticosteroids or anti-inflammatory agents. The platform could include:

• Micronized hydrophobic steroid suspensions.
• Preservative-free multidose delivery.
• Unit-dose suspension packaging.
• Low-viscosity redispersible vehicles.
• Enhanced wetting systems.
• Temperature-stable ophthalmic suspensions.
• Combination products with antihistamines or mast-cell stabilizers.

The same platform may support loteprednol etabonate products at different strengths or in different delivery formats. It could also support lifecycle management around post-surgical inflammation, dry-eye inflammation, and allergic eye disease, subject to separate clinical and regulatory requirements.

How does ALREX compare with competing loteprednol products?

Product	Active ingredient	Strength	Dosage form or positioning	Excipient-led opportunity
ALREX	Loteprednol etabonate	0.2%	Ophthalmic suspension for seasonal allergic conjunctivitis	Better comfort, preservative-free delivery, redispersion
LOTEMAX	Loteprednol etabonate	0.5%	Ophthalmic steroid products for inflammatory conditions	Different strength, vehicle, and indication strategy
LOTEMAX SM	Loteprednol etabonate	0.38%	Gel-forming ophthalmic product	Gel technology and dosing convenience
EYSUVIS	Loteprednol etabonate	0.25%	Short-course dry-eye treatment	Alternative strength, indication, and suspension design

The closest technical competitors are not limited to 0.2% loteprednol products. A developer must also assess higher-strength loteprednol products, gel-forming systems, fluorometholone products, prednisolone acetate suspensions, and nonsteroidal anti-inflammatory ophthalmics.

ALREX's commercial differentiation is its indication and lower-strength profile. A new product would need to avoid an undifferentiated "me-too" position against established loteprednol products.

What manufacturing and intellectual-property barriers affect ALREX opportunities?

Manufacturing scale-up is a meaningful barrier because ophthalmic suspensions require tight control of particle engineering and aseptic processing.

Key manufacturing controls include:

• Micronization or wet-milling parameters.
• Particle-size distribution and agglomeration control.
• Sterile filtration of the vehicle where feasible.
• Aseptic filling and terminal process validation.
• Homogeneous drug distribution during filling.
• Bottle inversion and shaking performance.
• Dropper-orifice consistency.
• Container-closure integrity.
• In-use microbiological stability.

The most defensible intellectual property is likely to arise from a defined combination of particle engineering, excipient ratio, process conditions, and packaging. Broad claims directed only to loteprednol etabonate with a common ophthalmic excipient may face prior-art and enablement challenges.

Which companies are positioned to challenge or extend ALREX?

Bausch + Lomb has the strongest commercial position because it owns the ALREX brand and broader loteprednol franchise. Generic ophthalmic manufacturers can compete through ANDA development, while specialty ophthalmic companies can pursue differentiated vehicles and preservative-free packaging.

Potential competitor categories include:

Competitor type	Commercial strategy
Generic manufacturers	Lower-priced 0.2% suspension
Specialty ophthalmic companies	Preservative-free or comfort-focused product
Contract development manufacturers	Platform formulation and aseptic filling
Device companies	Multidose preservative-free container systems
Branded ophthalmic companies	New indication, strength, or delivery system
Combination-product developers	Steroid plus antihistamine or mast-cell stabilizer

No biosimilar pathway applies to ALREX because loteprednol etabonate is a chemically synthesized small molecule, not a biologic. Competition would proceed through the generic drug pathway or a 505(b)(2) application, depending on the product's formulation, delivery system, strength, or clinical positioning [4].

What revenue exposure and commercial upside are associated with ALREX?

Bausch + Lomb does not generally disclose ALREX revenue as a standalone line item in public financial reporting. Revenue exposure must therefore be assessed through the broader ophthalmic pharmaceuticals portfolio rather than a separately reported ALREX figure.

Commercial upside depends on the product's position:

Product strategy	Pricing potential	Development complexity	Main risk
Standard generic suspension	Low	Moderate	Price erosion and substitution
Premium preservative-free unit dose	Moderate to high	Moderate	Packaging cost and adherence
Preservative-free multidose	High	High	Device and sterility validation
Improved-comfort suspension	Moderate	High	Need for convincing clinical differentiation
505(b)(2) reformulation	High if differentiated	High	Clinical and regulatory requirements
Combination product	High	High	Clinical development and patent scope

The most attractive opportunity is a differentiated product that reduces ocular-surface burden while preserving the efficacy and safety profile expected from loteprednol etabonate. A standard generic can capture volume, but margins are likely to compress as additional suppliers enter.

What litigation and settlement issues affect ALREX?

Relevant litigation questions include whether any current Orange Book-listed patent covers ALREX, whether an ANDA applicant has filed a Paragraph IV certification, whether Bausch + Lomb filed suit within the statutory period, and whether any settlement restricts generic launch timing.

A settlement can provide a generic applicant with a licensed entry date before patent expiration, but no commercial conclusion should be drawn without reviewing the actual agreement, court docket, and Orange Book listing. Method-of-use patents can also affect labeling. A generic may seek a section viii carve-out for a patented use if the unpatented indication remains approvable [2,4].

Key Takeaways

• ALREX is a 0.2% loteprednol etabonate ophthalmic suspension for seasonal allergic conjunctivitis.
• Its excipient system includes tyloxapol, povidone, glycerin, sodium chloride, boric acid, edetate disodium, sodium hydroxide, and purified water.
• The main technical challenges are suspension uniformity, particle settling, redispersion, dose delivery, sterility, and ocular comfort.
• The strongest commercial opportunity is a preservative-free or low-irritation product supported by a differentiated container or suspension technology.
• Original ALREX composition exclusivity has elapsed; current commercial risk turns on Orange Book listings, ANDA approvals, formulation patents, and generic entry.
• No biosimilar pathway applies. Generic or 505(b)(2) pathways are the relevant routes.
• Formulation, manufacturing-process, and container-closure patents offer the most practical protection for a follow-on product.
• Product-level ALREX revenue is not separately disclosed by Bausch + Lomb, so exposure must be evaluated within the company's broader ophthalmic portfolio.

FAQs

Can an ALREX generic use different excipients?

Yes. An ANDA applicant can use different inactive ingredients if the product satisfies FDA requirements for safety, pharmaceutical equivalence, bioequivalence, quality, and performance.

Is ALREX a solution or a suspension?

ALREX is an ophthalmic suspension. Patients must shake the bottle before use to redistribute loteprednol etabonate particles.

Could a preservative-free ALREX product receive premium pricing?

Yes. A preservative-free multidose or unit-dose product could command a premium if it demonstrates improved comfort, tolerability, usability, or adherence. Packaging and sterility costs would reduce gross margin.

Can ALREX be converted into an ophthalmic gel?

Yes, but conversion to a gel would create a new formulation and development program. The developer would need to establish dose uniformity, rheology, drop delivery, stability, sterility, ocular tolerability, and regulatory comparability.

What is the most valuable excipient patent opportunity for ALREX?

A patent combining particle-size control, a defined wetting and viscosity system, improved redispersion, and a preservative-free container would likely provide more commercial value than a patent covering a single conventional excipient.

References

1. U.S. Food and Drug Administration. (n.d.). ALREX (loteprednol etabonate ophthalmic suspension) prescribing information. Bausch + Lomb.
2. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
3. U.S. Food and Drug Administration. (2013). Sterile drug products produced by aseptic processing: Current good manufacturing practice.
4. U.S. Food and Drug Administration. (2023). ANDA submissions: Refuse-to-receive standards.