List of Excipients in Branded Drug PROLENSA

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Bausch & Lomb Incorporated	PROLENSA	bromfenac sodium	24208-602	BENZALKONIUM CHLORIDE
Bausch & Lomb Incorporated	PROLENSA	bromfenac sodium	24208-602	BORIC ACID
Bausch & Lomb Incorporated	PROLENSA	bromfenac sodium	24208-602	EDETATE DISODIUM

PROLENSA Excipient Strategy and Commercial Opportunities

Last updated: August 10, 2026

PROLENSA is a once-daily bromfenac ophthalmic solution used for the treatment of postoperative inflammation and prevention of ocular pain in patients undergoing cataract surgery. Its commercial differentiation depends on more than bromfenac concentration. The formulation uses buffering, chelation, viscosity modification, antioxidant protection, and pH control to support chemical stability, ocular tolerability, and once-daily dosing.

The principal commercial opportunities are preservative-free delivery, sulfite-free stabilization, improved multidose packaging, lower-irritation formulations, and generic or branded products that match PROLENSA’s dosing convenience while reducing formulation-related liabilities.

What excipients are in PROLENSA?

PROLENSA contains bromfenac sodium sesquihydrate equivalent to 0.07% bromfenac. The inactive ingredients listed in the prescribing information are boric acid, edetate disodium, povidone, sodium borate decahydrate, sodium sulfite, sodium hydroxide, and water for injection. The product is supplied as a sterile topical ophthalmic solution.[1]

Component	Likely formulation function	Commercial relevance
Boric acid	Buffering and tonicity control	Helps maintain ocularly acceptable pH and osmolality
Sodium borate decahydrate	Borate buffering system	Supports pH stability and bromfenac solubility
Edetate disodium	Chelating agent	Binds trace metals that can accelerate oxidation
Povidone	Viscosity modifier and lubricant	May improve residence time and ocular comfort
Sodium sulfite	Antioxidant	Protects bromfenac or other formulation components from oxidative degradation
Sodium hydroxide	pH adjustment	Controls final formulation pH
Water for injection	Aqueous vehicle	Provides the sterile delivery medium

The label also identifies sodium sulfite as a potential source of allergic-type reactions, including anaphylactic symptoms and asthmatic episodes in susceptible patients.[1]

How does PROLENSA’s excipient system support product performance?

PROLENSA’s excipient strategy addresses the central formulation challenges of topical ophthalmic NSAIDs: low ocular residence time, hydrolytic or oxidative instability, pH sensitivity, and the need to minimize dosing frequency.

Buffering and pH control

The boric acid and sodium borate system establishes a controlled aqueous environment. Bromfenac’s solubility and chemical stability can change with pH, making the buffer system commercially important even though it is not itself a therapeutic ingredient.

The pH must balance several competing requirements:

• Bromfenac solubility
• Chemical stability during shelf life
• Ocular tolerability
• Compatibility with the container closure
• Drop consistency during repeated use

A generic developer that changes the buffer ratio, pH, or ionic strength may achieve pharmaceutical equivalence but still face development risk from precipitation, degradation, variable delivery, or increased ocular discomfort.

Chelation with edetate disodium

Edetate disodium is commonly used in ophthalmic formulations to bind trace metal ions. Metal contamination can catalyze oxidation and reduce stability. In PROLENSA, the chelator likely works with sodium sulfite to control oxidative degradation.

The commercial implication is that the antioxidant system may not be fully replaceable by a single excipient. A developer removing edetate disodium would need to demonstrate that the substitute stabilization strategy maintains impurity limits through the proposed shelf life.

Povidone and ocular residence time

Povidone can increase viscosity and provide a lubricating effect. In a topical ophthalmic solution, modest viscosity modification may slow drainage through the nasolacrimal system and improve surface contact without creating the administration problems associated with gels or suspensions.

Povidone concentration is a potential design-around variable. Changing its molecular weight or concentration can affect:

• Drop size
• Spreadability
• Blinking sensation
• Residence time
• Initial blur
• Container-drug interaction
• Patient preference

The formulation opportunity is to preserve once-daily dosing while improving comfort and reducing transient visual disturbance.

Sodium sulfite and oxidative protection

Sodium sulfite is a meaningful technical component because it may protect the formulation from oxidation. Its presence also creates a market opportunity for sulfite-free alternatives.

A sulfite-free product could use a different antioxidant, oxygen-reduction strategy, chelation system, nitrogen headspace, light-protective packaging, or a combination of these approaches. Each option creates new regulatory and manufacturing requirements. The substitute must be compatible with ocular administration and must not introduce new irritation, discoloration, particulate, or extractables risks.

What formulation opportunities exist for PROLENSA competitors?

The strongest opportunities are products that retain the clinical convenience of once-daily bromfenac while improving tolerability, packaging, or stability.

Sulfite-free bromfenac ophthalmic solution

A sulfite-free formulation is the clearest excipient-driven opportunity. It could target patients with known sulfite sensitivity or clinicians seeking to avoid sulfite exposure in the postoperative setting.

The development challenge is replacing the oxidative protection provided by sodium sulfite without reducing shelf life. Potential strategies include:

• Alternative ophthalmic-grade antioxidants
• Lower dissolved oxygen
• Improved container oxygen barrier
• Chelator optimization
• Light-resistant packaging
• Nitrogen flushing
• Single-dose packaging

A sulfite-free claim would require comparative stability data and a clear clinical-tolerability rationale. It would not, by itself, establish superior efficacy.

Preservative-free multidose delivery

PROLENSA’s listed excipients do not include benzalkonium chloride. That creates a distinction from many preserved ophthalmic products, but a product should not be described as preservative-free merely because it lacks benzalkonium chloride. Sodium sulfite is an antioxidant, not a conventional antimicrobial preservative.

A commercial competitor could pursue:

1. A conventional multidose bottle with validated microbial protection.
2. A preservative-free multidose container using a one-way valve or sterilizing filter.
3. Unit-dose ampoules for high-sensitivity patients.
4. A low-waste multidose device for postoperative use.

The key value proposition is reduced ocular-surface exposure to preservatives without sacrificing usability. Packaging is likely to become as important as the excipient composition.

Lower-irritation formulations

Postoperative patients often use multiple topical products, including antibiotics, corticosteroids, and NSAIDs. A formulation that reduces burning, stinging, or transient blur could compete even without changing the active ingredient.

Relevant levers include:

• Tighter pH control
• Reduced ionic strength
• Optimized osmolality
• Alternative buffering systems
• Lower viscosity or different povidone grade
• Reduced sulfite concentration
• Improved drop-size control

These changes must be assessed against ocular-surface tolerability, corneal healing, preservative exposure, and dosing accuracy.

Unit-dose and combination products

A unit-dose bromfenac product could reduce contamination concerns and simplify postoperative regimens. Its disadvantages are higher packaging cost, increased material consumption, and potentially lower patient adherence if the patient must open multiple units.

A fixed-combination product containing bromfenac and another postoperative agent could create convenience value, but it would face formulation compatibility and regulatory complexity. The most commercially practical combination opportunity may be coordinated packaging rather than a single bottle.

How does PROLENSA compare with competing ophthalmic NSAIDs?

PROLENSA competes primarily on dosing frequency, bromfenac potency, formulation performance, and postoperative convenience.

Product or active ingredient	Typical concentration	Common dosing positioning	Formulation or commercial consideration
PROLENSA, bromfenac	0.07% bromfenac	Once daily after cataract surgery	Branded once-daily solution with sulfite-containing excipient system
Bromfenac 0.09% products	0.09% bromfenac	Often once or twice daily depending on product	Generic and legacy branded competition
Xibrom, bromfenac	0.09%	Twice daily historical positioning	Earlier bromfenac product
Bromday, bromfenac	0.09%	Once daily historical positioning	Earlier once-daily bromfenac product
NEVANAC, nepafenac	0.1% nepafenac	Multiple daily doses	Prodrug approach and suspension formulation
ILEVRO, nepafenac	0.3% nepafenac	Once daily	Direct once-daily NSAID competitor
Ketorolac ophthalmic	0.4% or 0.5% depending on product	Multiple daily doses	Low-cost generic competition
Diclofenac ophthalmic	0.1%	Multiple daily doses	Generic and legacy competition

The closest branded commercial comparison is ILEVRO because both products offer once-daily postoperative NSAID dosing. PROLENSA’s opportunity is to differentiate through bromfenac formulation, comfort, bottle design, and supply reliability rather than concentration alone.

What FDA regulatory status and exclusivity apply to PROLENSA?

PROLENSA was approved by the U.S. Food and Drug Administration under NDA 205530 in 2013 for the treatment of postoperative inflammation and prevention of ocular pain in patients undergoing cataract surgery.[1][2]

Regulatory issue	PROLENSA position
Active ingredient	Bromfenac sodium sesquihydrate
Strength	Equivalent to 0.07% bromfenac
Dosage form	Sterile ophthalmic solution
Administration	One drop once daily, beginning one day before surgery and continuing through the first 14 days after surgery, according to labeling
U.S. approval pathway	505(b)(2) or new-drug application framework reflected by the NDA
Sponsor and commercial owner	Bausch + Lomb commercialized the product; ownership history traces to ISTA Pharmaceuticals
Therapeutic area	Postoperative ocular inflammation and pain
Pediatric status	Not established for routine pediatric use under the product labeling

The three-year exclusivity associated with a new clinical investigation supporting an NDA would not be the principal barrier to current generic entry. Commercial barriers now depend more heavily on Orange Book-listed patents, non-listed formulation and manufacturing know-how, FDA product-specific requirements, and the economics of ophthalmic manufacturing.[2][3]

What patents protect PROLENSA and how strong is the formulation estate?

PROLENSA’s commercial protection is likely to involve a combination of active-ingredient, formulation, dosing, and manufacturing claims rather than a single excipient patent.

The relevant claim categories are:

• Bromfenac ophthalmic compositions at defined concentrations
• Once-daily postoperative treatment methods
• Buffer systems and pH ranges
• Stability-enhancing excipient combinations
• Antioxidant and chelator systems
• Viscosity-modified aqueous solutions
• Container and delivery systems
• Manufacturing processes that control impurities and sterility

Formulation patents can be commercially useful even when the active ingredient is old. A generic applicant may be able to use the same bromfenac concentration while avoiding one claimed excipient combination. A narrow claim covering the complete composition may be easier to design around than a broader method-of-use claim, but the practical outcome depends on the exact patent language and Orange Book listing.

Paragraph IV and generic entry risk

A generic bromfenac applicant may file an ANDA with a Paragraph IV certification against unexpired listed patents. The principal litigation questions would include:

1. Whether the proposed formulation falls within the asserted composition claims.
2. Whether the once-daily method is an approved labeling requirement or can be carved out.
3. Whether the proposed excipient system is materially different.
4. Whether the patent claims are obvious in view of earlier bromfenac ophthalmic products.
5. Whether the listed patents remain enforceable and relevant to the proposed product.

A successful Paragraph IV challenge could permit launch before patent expiry. A settlement could delay entry until an agreed date, subject to antitrust and regulatory considerations.

What manufacturing and intellectual-property barriers affect generic launch?

Ophthalmic products have higher manufacturing sensitivity than many oral solid-dose products. A prospective PROLENSA competitor must control:

• Sterility assurance
• Particulate matter
• Drop uniformity
• Fill volume
• Container closure integrity
• Extractables and leachables
• Bromfenac degradation products
• Oxygen exposure
• pH drift
• Viscosity variation
• Microbial contamination during repeated use

The excipient system creates specific manufacturing dependencies. Sodium sulfite concentration can affect oxidative protection and tolerability. Povidone grade can affect viscosity and drop formation. Borate ratios can affect pH and compatibility. Edetate disodium can interact with trace metals and packaging components.

These attributes may not create a complete legal barrier, but they can raise development cost, increase stability-study burden, and delay FDA approval.

What licensing and partnership opportunities exist?

The most attractive licensing opportunities are likely to sit outside the bromfenac molecule itself.

Delivery-device licensing

A device company with a validated preservative-free multidose ophthalmic system could license its platform to a bromfenac developer. The commercial value would come from platform reuse across antibiotics, corticosteroids, NSAIDs, and glaucoma products.

Excipient and stabilization technology

A sulfite-free stabilization platform could support a differentiated bromfenac product and be extended to other oxidation-sensitive ophthalmic drugs. The strongest asset would be a formulation package that includes composition claims, stability data, and compatible packaging.

Contract manufacturing

A manufacturer with sterile ophthalmic filling, low-volume ophthalmic production, and validated multidose packaging could become a strategic partner. Supply reliability is commercially relevant because ophthalmic shortages can rapidly affect prescriber substitution and formulary positioning.

Regional commercialization

Bausch + Lomb has global ophthalmology capabilities, but regional rights may still be commercially relevant where branded bromfenac, generic substitution, or local registration requirements differ. Geographic opportunities depend on national patent status, regulatory exclusivity, reimbursement, and local manufacturing rules.

What is the revenue exposure and competitive outlook for PROLENSA?

Bausch + Lomb does not generally report PROLENSA revenue as a separately disclosed public line item in its principal financial reporting. Revenue exposure must therefore be assessed through the broader ophthalmic pharmaceutical portfolio rather than a verified standalone PROLENSA figure.[4]

The product’s commercial strengths are:

• Once-daily dosing
• Established postoperative indication
• Recognized bromfenac brand
• Ophthalmology-focused commercial infrastructure
• Potential patient and prescriber preference for lower dosing frequency

The principal risks are:

• Generic bromfenac substitution
• Once-daily competition from nepafenac
• Price erosion
• Limited differentiation from other topical NSAIDs
• Sulfite sensitivity concerns
• Reimbursement pressure
• Formulation and device replication

A differentiated successor product would need a measurable advantage, such as sulfite-free delivery, preservative-free multidose use, reduced ocular discomfort, lower waste, or improved adherence.

Key Takeaways

• PROLENSA uses borate buffering, edetate disodium, povidone, sodium sulfite, sodium hydroxide, and water for injection around bromfenac 0.07%.
• Sodium sulfite is the most visible excipient-related commercial liability because the label includes a sulfite sensitivity warning.
• The strongest product opportunity is a sulfite-free, preservative-free, once-daily bromfenac formulation with validated multidose packaging.
• Povidone, buffer composition, chelation, pH, and antioxidant protection are central design variables.
• The closest branded comparator is ILEVRO, while generic bromfenac and ketorolac products create price pressure.
• Current generic risk depends on patents, FDA requirements, manufacturing capability, and the economics of sterile ophthalmic production.
• PROLENSA’s standalone revenue is not separately disclosed in public company reporting.
• Device licensing, stabilization technology, and ophthalmic contract manufacturing are the most practical adjacent commercial opportunities.

FAQs

Can PROLENSA be reformulated without sodium sulfite?

Yes. A developer could replace sodium sulfite with another stabilization system or use packaging and manufacturing controls that reduce oxidation. The replacement must support sterility, stability, ocular tolerability, and regulatory comparability.

Is PROLENSA preservative-free?

The labeled inactive ingredients do not include benzalkonium chloride or another conventional antimicrobial preservative. Sodium sulfite is listed as an antioxidant. The product’s regulatory and commercial description should follow the approved labeling and packaging configuration.

What is the most defensible excipient patent strategy for a PROLENSA follow-on?

A defensible strategy would combine a specific buffer-chelator-antioxidant system with defined pH, viscosity, stability, and packaging parameters. Broad claims covering routine ophthalmic excipients may face validity and obviousness challenges.

Could a generic use different excipients from PROLENSA?

Yes. An ANDA applicant generally may use a different inactive-ingredient system if the product meets applicable sameness, safety, performance, stability, and bioequivalence requirements. The applicant must also address any relevant patents.

Is a once-daily bromfenac product commercially differentiated from ketorolac?

Usually, yes. Once-daily dosing can support adherence and postoperative convenience. The advantage is commercially meaningful only if the product also achieves competitive pricing, tolerability, access, and supply reliability.

References

1. Bausch + Lomb. (2023). PROLENSA (bromfenac ophthalmic solution) prescribing information. U.S. Food and Drug Administration labeling repository.

2. U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drugs, NDA 205530. https://www.accessdata.fda.gov/scripts/cder/daf/

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-data-files

4. Bausch + Lomb Corporation. (2024). Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. U.S. Securities and Exchange Commission.