List of Excipients in Branded Drug OMIDRIA

Company	Tradename	Ingredient	NDC	Excipient	Potential Generic Entry
Omeros Corporation	OMIDRIA	phenylephrine and ketorolac	62225-600	CITRIC ACID MONOHYDRATE
Omeros Corporation	OMIDRIA	phenylephrine and ketorolac	62225-600	TRISODIUM CITRATE DIHYDRATE
Omeros Corporation	OMIDRIA	phenylephrine and ketorolac	62225-600	WATER
Rayner Surgical Inc	OMIDRIA	phenylephrine and ketorolac	82604-600	CITRIC ACID MONOHYDRATE
Rayner Surgical Inc	OMIDRIA	phenylephrine and ketorolac	82604-600	TRISODIUM CITRATE DIHYDRATE
Rayner Surgical Inc	OMIDRIA	phenylephrine and ketorolac	82604-600	WATER

OMIDRIA Excipient Strategy and Commercial Opportunities

Last updated: August 5, 2026

OMIDRIA is a preservative-free, single-use ophthalmic solution combining phenylephrine hydrochloride and ketorolac tromethamine for use during cataract surgery and intraocular lens implantation. Its excipient strategy is intentionally narrow: aqueous vehicle, citrate buffering, and pH adjustment support chemical stability, ocular tolerability, and operating-room convenience. The commercial opportunity is less likely to come from novel excipients than from preservative-free packaging, ready-to-use delivery, validated stability, hospital contracting, and differentiated formulations for ophthalmic surgery.

What is OMIDRIA and how does its formulation work?

OMIDRIA contains two active ingredients:

Component	Concentration	Functional role
Phenylephrine hydrochloride	1%	Maintains or enlarges the pupil during surgery
Ketorolac tromethamine	0.3%	Reduces intraoperative miosis and postoperative ocular pain

The product is supplied as a concentrate that is diluted into an ophthalmic irrigation solution before use. The FDA-approved label identifies the inactive ingredients as sodium citrate dihydrate, citric acid monohydrate, sodium hydroxide and/or hydrochloric acid for pH adjustment, and water for injection.[1]

The formulation is preservative-free. That characteristic is commercially important because the product is used directly in the anterior chamber during surgery. Avoiding benzalkonium chloride and other antimicrobial preservatives reduces concerns about epithelial toxicity and intraocular exposure.

What does each excipient do?

Excipient	Primary formulation function	Commercial relevance
Sodium citrate dihydrate	Buffering and pH control	Supports stability of the active ingredients
Citric acid monohydrate	Buffering and pH control	Works with citrate to control acidity
Sodium hydroxide and hydrochloric acid	Final pH adjustment	Enables batch-to-batch pH control
Water for injection	Sterile aqueous vehicle	Supports parenteral-grade manufacturing and ophthalmic use

The excipient burden is low. That reduces formulation complexity, but it also limits opportunities to differentiate the product through proprietary inactive ingredients.

What is the excipient strategy behind OMIDRIA?

OMIDRIA’s excipient strategy has four commercial objectives.

Preservative-free intraocular exposure

The product avoids conventional ophthalmic preservatives. This is relevant because surgery places the solution in close contact with sensitive ocular tissues, and preservatives can create tolerability concerns in repeated or prolonged topical use.

For an intraoperative product, preservative-free status is more valuable than a complex antimicrobial system. Sterility is achieved through manufacturing controls, container-closure integrity, and the product’s single-use format rather than through a preservative.

Narrow pH-control system

The citrate and citric acid combination provides a simple buffer system. Sodium hydroxide or hydrochloric acid permits final pH adjustment during manufacture.

A narrow buffer system can reduce the number of variables affecting:

• Active-ingredient stability
• Ocular tolerability
• Compatibility with the irrigation solution
• Sterilization and filling operations
• Lot-release testing

The trade-off is that the manufacturer must tightly control pH, osmolality, concentration, container interaction, and dilution performance.

Compatibility with intraoperative dilution

OMIDRIA is designed to be diluted into an ophthalmic irrigation solution used during surgery. The excipients therefore must remain compatible with the final diluted environment and must not generate visible particles, precipitation, unacceptable pH shifts, or clinically meaningful changes in osmolality.

This creates a product-specific performance requirement. A generic or follow-on product cannot rely only on matching the labeled active concentrations. It must demonstrate pharmaceutical equivalence and adequate performance after dilution.

Single-use sterile presentation

The single-use format limits the need for preservatives and reduces contamination risk in the operating room. Packaging, fill volume, withdrawal performance, and dilution instructions become part of the product’s value proposition.

The packaging system can be more commercially defensible than the excipients themselves. A reliable vial, ampoule, or other container that minimizes transfer steps can reduce preparation errors and support operating-room efficiency.

What commercial opportunities exist for OMIDRIA excipients?

The strongest opportunities are in manufacturing, packaging, supply-chain control, and product extensions rather than in selling the individual excipients.

Excipient supply and dual sourcing

Citrate salts, citric acid, sodium hydroxide, hydrochloric acid, and water for injection are widely available pharmaceutical materials. They are not likely to create durable exclusivity individually.

Their commercial value lies in:

• Compendial quality
• Low endotoxin levels
• Consistent trace-metal control
• Reliable global supply
• Validated compatibility with the active ingredients
• Sterile manufacturing capability
• Documented change-control procedures

A contract manufacturer or excipient supplier could compete by offering qualified, low-variability materials and integrated sterile fill-finish services.

Preservative-free ophthalmic platforms

OMIDRIA’s formulation architecture can support a broader platform for intraoperative ophthalmic products. Potential adjacent products include:

• Phenylephrine-only irrigation solutions
• Ketorolac-only intraoperative solutions
• Combination products with other anti-inflammatory agents
• Products for vitreoretinal surgery
• Products for glaucoma procedures
• Preservative-free postoperative ophthalmic preparations

The regulatory burden would depend on whether the product is a new drug, an abbreviated new drug application, a reformulation, or a line extension. A new excipient or materially different concentration could require additional safety and compatibility work.

Ready-to-use or lower-complexity presentations

A commercial extension could reduce preparation steps by providing a ready-to-use irrigation solution rather than a concentrate requiring dilution. The opportunity would depend on stability, container size, shipping cost, and the ability to maintain a commercially practical shelf life.

A ready-to-use product could also increase packaging volume and logistics costs. The value proposition must therefore be measured against pharmacy labor, operating-room time, preparation errors, and waste.

Alternative buffer systems

Alternative buffering agents, including phosphate or other physiologically compatible systems, could be evaluated for stability or tolerability advantages. Such changes would not be commercially meaningful unless they improve at least one measurable attribute:

• Longer shelf life
• Better stability under temperature excursions
• Lower particulate risk
• Improved compatibility after dilution
• Reduced manufacturing cost
• Better container compatibility

A buffer substitution would likely trigger comparative stability, analytical, and regulatory work. It could also create freedom-to-operate issues if the revised formulation falls within existing formulation claims.

What formulations are protected by OMIDRIA-related intellectual property?

The core intellectual-property value is more likely to reside in the combination of phenylephrine and ketorolac, ophthalmic-surgery use, concentration ranges, dilution conditions, and formulation characteristics than in citrate or water for injection alone.

Formulation patent considerations

Potential claim categories include:

• A combination of phenylephrine and ketorolac
• Specific concentration ranges
• Use during cataract surgery
• Prevention of intraoperative miosis
• Reduction of postoperative pain
• Preservative-free ophthalmic compositions
• Stability or pH ranges
• Dilution into an irrigation solution
• Single-dose or single-use presentations

The individual excipients are established pharmaceutical materials. Their use in isolation would generally provide little patent protection. A patent position may become stronger when the excipient system is claimed in combination with the active ingredients and a defined surgical-use method.

Patent scope must be assessed claim by claim. A supplier that changes the buffer, concentration, or container may avoid one claim while remaining within another.

Regulatory exclusivity versus patent exclusivity

OMIDRIA received FDA approval in 2014.[2] It is a small-molecule drug, not a biologic. Biosimilar approval under the Public Health Service Act is therefore not the relevant competitive pathway. Competition would normally arise through an abbreviated new drug application, a 505(b)(2) application, or a full new drug application.

FDA regulatory exclusivity and patent protection are separate. Regulatory exclusivity may prevent certain approvals for a defined period, while patents can extend beyond that period. The commercial entry date depends on the later of applicable regulatory barriers, patent constraints, litigation outcomes, and settlement terms.

When does OMIDRIA lose exclusivity?

OMIDRIA’s practical loss-of-exclusivity analysis requires four separate checks:

Barrier	Commercial question
FDA approval history	What regulatory exclusivity remains, if any?
Orange Book listings	Which patents are listed against the approved product?
Patent term	What are the expiration dates after patent-term adjustment or extension?
Litigation and settlements	Has an ANDA filer obtained a licensed or agreed launch date?

The 2014 approval date means the original new-drug exclusivity period is no longer the principal barrier. The remaining risk is generally patent-based, product-specific, and dependent on the current Orange Book record and any litigation or settlement agreements.

A Paragraph IV certification could challenge listed patents by asserting that they are invalid, unenforceable, or not infringed. The patent holder may then file an infringement action within the statutory period, potentially triggering a 30-month stay of FDA approval under the Hatch-Waxman framework.[3]

Which companies could challenge OMIDRIA?

The most likely challengers are generic ophthalmic manufacturers with:

• Sterile ophthalmic fill-finish capability
• Experience with ANDA development
• Access to preservative-free manufacturing
• Commercial relationships with ambulatory surgery centers
• Established distribution to ophthalmologists and hospital systems

Potential competitors would not need to reproduce every excipient exactly if they can demonstrate pharmaceutical equivalence, bioequivalence where applicable, and adequate product quality under the applicable FDA pathway.

The principal technical barriers are:

1. Maintaining active stability in a concentrated aqueous system.
2. Controlling pH and osmolality after dilution.
3. Demonstrating sterility and container-closure integrity.
4. Showing acceptable particulate and extractables profiles.
5. Establishing comparable performance in the surgical irrigation environment.
6. Avoiding listed-patent infringement.

What generic entry risks exist for OMIDRIA?

Generic entry could pressure price through hospital and ambulatory-surgery-center purchasing contracts. The impact would depend on whether the competitor offers the same concentrate format, a ready-to-use solution, or a lower-cost alternative requiring more preparation.

Likely generic launch scenarios

Scenario	Competitive effect
First generic matches the concentrate format	Direct price competition and formulary substitution
Generic uses a different buffer	Potential differentiation, but higher regulatory and technical burden
Ready-to-use competitor launches	Convenience-based competition and possible premium pricing
Hospital-compounded alternative expands	Lower acquisition cost but greater preparation and quality-control burden
Patent settlement permits delayed entry	Predictable erosion beginning on the agreed launch date

A generic may initially target high-volume cataract centers rather than the full ophthalmic market. Contracting, wholesaler access, and surgeon familiarity could determine uptake as much as price.

How strong is the OMIDRIA patent estate?

The patent estate should be considered moderate rather than inherently strong based solely on the excipient profile.

Strengths

• Combination of two active ingredients in a surgical setting
• Specific intraoperative use case
• Preservative-free positioning
• Potential claims covering concentration, dilution, and administration
• Clinical and operational value from one coordinated product

Weaknesses

• Excipients are conventional and widely used
• The formulation is aqueous and compositionally simple
• Generic developers may design around individual formulation claims
• Small-molecule products face conventional ANDA competition
• Patent strength depends on claim construction and prosecution history, not on the number of listed patents

The strongest defensibility is likely to come from claims that connect the composition to a defined surgical result or use condition. Broad claims covering only common excipients would face greater validity and obviousness pressure.

What is the FDA and Orange Book status of OMIDRIA?

OMIDRIA is an FDA-approved prescription ophthalmic product for use during cataract surgery or intraocular lens implantation.[1] Because it is a small-molecule drug, the relevant competitive framework is the Federal Food, Drug, and Cosmetic Act and Hatch-Waxman, not biosimilar interchangeability.

The Orange Book should be reviewed for:

• Active patent listings
• Patent use codes
• Pediatric exclusivity
• Approval status
• Reference listed drug designation
• Any approved generic or authorized-generic entry

The listed patent record can change through delisting, expiration, correction, or new FDA submissions. The current Orange Book entry is therefore the controlling source for an up-to-date listing analysis.[4]

How do licensing deals affect OMIDRIA’s commercial opportunity?

Commercial rights can materially affect market access even when formulation and patent rights remain unchanged. A rights holder may use a licensing or commercialization agreement to transfer:

• U.S. sales responsibility
• Hospital contracting
• Distribution
• Manufacturing
• Regulatory maintenance
• Lifecycle-management rights

For OMIDRIA, the commercial value of an agreement would depend on territory, royalty rate, minimum purchase obligations, supply commitments, and control over patent enforcement. A licensee with an established ophthalmology sales force could improve penetration without changing the formulation.

Deal diligence should test whether the agreement covers only OMIDRIA or also related formulations, pipeline products, manufacturing know-how, and future indications.

How can OMIDRIA improve its excipient and formulation strategy?

The highest-value development priorities are operational.

Prioritize stability and supply resilience

The manufacturer should qualify multiple sources for citrate, citric acid, sodium hydroxide, hydrochloric acid, and water for injection. Each source change requires comparability controls, but dual sourcing can reduce supply disruption risk.

Protect the container-closure system

Extractables and leachables, adsorption, silicone interaction, stopper compatibility, and particulate generation should be monitored across the product shelf life. Packaging improvements may create more practical differentiation than changing the buffer.

Evaluate a ready-to-use presentation

A ready-to-use format could reduce pharmacy preparation steps, but its economics must account for shipping volume, shelf life, cold-chain exposure if applicable, and operating-room waste.

Develop adjacent preservative-free products

A platform strategy using the same sterile manufacturing network could support additional intraoperative products. The most attractive candidates would share:

• Similar fill-finish requirements
• Comparable pH and osmolality controls
• Existing ophthalmic distribution
• A clear reduction in surgical preparation burden

Key Takeaways

• OMIDRIA uses a simple preservative-free aqueous formulation based on citrate buffering, pH adjustment, and water for injection.
• The individual excipients offer limited standalone patent value because they are conventional pharmaceutical ingredients.
• Commercial defensibility comes from the combined active ingredients, surgical use, sterile single-use presentation, stability, and operating-room workflow.
• OMIDRIA is a small-molecule product. Generic competition, not biosimilar substitution, is the relevant market risk.
• A Paragraph IV challenge would focus on listed patents covering the combination, concentrations, formulation, dilution, or method of use.
• The strongest lifecycle opportunities are ready-to-use packaging, additional preservative-free intraoperative products, supply-chain resilience, and hospital workflow differentiation.
• The current Orange Book listing and patent litigation record determine the operative entry risk.

FAQs

Can OMIDRIA’s citrate excipients be replaced without creating a new product?

A buffer substitution may be possible, but it would require comparative stability, pH, osmolality, particulate, sterility, container-compatibility, and regulatory assessments. It could also affect patent clearance.

Is OMIDRIA eligible for a biosimilar competitor?

No. OMIDRIA contains small-molecule active ingredients and is generally subject to generic-drug or other small-molecule FDA pathways rather than the biosimilar pathway.

Could a preservative-free generic use different inactive ingredients?

Potentially. The applicant would need to establish pharmaceutical equivalence, product quality, stability, and compatibility with the labeled dilution and surgical-use conditions.

Does a ready-to-use OMIDRIA product have automatic market exclusivity?

No. A ready-to-use presentation would require its own regulatory and patent analysis. It could receive protection only to the extent supported by applicable patents, regulatory exclusivity, or differentiated approval status.

Are OMIDRIA’s excipients the main barrier to generic entry?

No. The main barriers are sterile ophthalmic manufacturing, active-ingredient stability, dilution performance, product quality, regulatory equivalence, container compatibility, and the scope of listed patents.

References

1. U.S. Food and Drug Administration. (2014). OMIDRIA (phenylephrine hydrochloride and ketorolac tromethamine) ophthalmic solution prescribing information.
2. U.S. Food and Drug Administration. (2014). New drug application approval: OMIDRIA.
3. U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act of 1984, Pub. L. No. 98-417.
4. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.