US Patent 8,784,789: Bepotastine Ophthalmic Formulation Scope, Expiration, and Patent Landscape

US Patent 8,784,789 protects aqueous formulations of bepotastine, particularly bepotastine besilate ophthalmic and nasal preparations containing a light-stabilizing concentration of a water-soluble metal chloride. The strongest commercial relevance is to Bepreve, the 1.5% bepotastine besilate ophthalmic solution. The core formulation limitation is a chloride concentration of 0.2% to 1.2% w/v, with claim 11 narrowing the range to 0.2% to 0.8% w/v for sodium chloride.

The patent is a formulation patent, not a basic compound or composition-of-matter patent. It does not broadly prevent manufacture of bepotastine. It targets aqueous products that use the claimed chloride-based light-stabilization approach, especially products containing bepotastine besilate, sodium chloride, phosphate buffer, benzalkonium chloride and water.

What drug and product does US Patent 8,784,789 cover?

The active ingredient identified in the claims is bepotastine, specifically the (+)-(S) stereoisomer:

(+)-(S)-4-[4-[(4-chlorophenyl)(2-pyridyl)methoxy]piperidino]butyric acid

The commercially relevant salt is bepotastine besilate, also called bepotastine benzenesulfonate. Bepreve is an ophthalmic solution containing bepotastine besilate at a strength equivalent to 1.5% bepotastine.[1]

Item	Description
Active ingredient	Bepotastine
Commercial salt	Bepotastine besilate
Main US product	Bepreve ophthalmic solution
Dosage form	Sterile aqueous eye drop
Strength	1.5% bepotastine besilate, labeled as bepotastine equivalent
Therapeutic category	Ophthalmic antihistamine and mast-cell stabilizer
FDA approval	Bepreve NDA 22-135, approved Sept. 8, 2009
Patent type	Aqueous formulation and light-stabilization patent
Patent number	US 8,784,789
Issue date	July 22, 2014
Patent owner or applicant	Ube Industries, Ltd., based on published patent-family records
Projected patent expiry	Approximately December 2029, subject to the official USPTO term calculation

The formulation described in the Bepreve labeling includes bepotastine besilate, sodium chloride, benzalkonium chloride, sodium phosphate, sodium hydroxide and purified water. That composition closely tracks the limitations in claims 10 and 11.[1]

What does US Patent 8,784,789 claim?

The patent has two principal claim groups.

Broad aqueous preparation claims

Claim 1 covers an aqueous liquid preparation containing:

Bepotastine or a pharmacologically acceptable acid-addition salt;
A water-soluble metal chloride;
Water;
A chloride concentration from 0.2% to 1.2% w/v; and
Optional buffer, preservative, chelating agent or flavor.

The chloride is used in a light-stabilizing effective amount. Claims 2 and 8 broaden the chloride identity to sodium chloride, potassium chloride, calcium chloride, alkali-metal chlorides and alkaline-earth-metal chlorides.

The claim is not limited to an eye drop. Claim 1 covers an aqueous liquid preparation generally, while claims 6 and 7 specify eye drops and nasal drops.

Narrow commercial formulation claims

Claims 9 through 11 target more defined ophthalmic compositions.

Claim	Principal limitations	Commercial significance
9	Aqueous eye drop containing bepotastine, water-soluble metal chloride, sodium dihydrogen phosphate buffer, preservative, water and optional disodium edetate	Covers a formulation class resembling Bepreve
10	Bepotastine formulation containing metal chloride, benzalkonium chloride, sodium dihydrogen phosphate dihydrate, sodium hydroxide and water	Closely tracks the labeled excipient architecture
11	Bepotastine monobenzenesulfonate, sodium chloride and sodium chloride at 0.2% to 0.8% w/v	The most product-specific claim and likely the central infringement risk for matching products

Claim 11 is particularly important because it identifies the besilate salt and narrows the chloride to sodium chloride. A generic ophthalmic product containing the same active salt and sodium chloride at a concentration within 0.2% to 0.8% w/v would face a direct literal-infringement issue if the remaining formulation limitations are also present.

How broad is the scope of claim 1?

Claim 1 has meaningful breadth because it does not restrict the product to an eye drop, a particular pH, a specific preservative or a specific chloride salt. A product may fall within claim 1 if it contains:

Bepotastine or an acceptable acid-addition salt;
Any qualifying water-soluble metal chloride;
An aqueous vehicle;
Chloride at 0.2% to 1.2% w/v; and
A light-stabilizing function attributable to the chloride.

The optional excipient language does not require a buffer, preservative, chelator or flavor. A formulation without those materials can still meet claim 1.

The claim has several limiting features that constrain enforcement.

The active ingredient is stereochemically defined

The claim requires the (+)-(S) form of bepotastine. A different stereoisomer or a racemic product could create a noninfringement argument, although regulatory equivalence and pharmacological performance would need separate assessment.

The claim also covers pharmacologically acceptable acid-addition salts. Claim 4 specifically identifies the monobenzenesulfonate salt, which is bepotastine besilate.

The chloride must be water-soluble and within a defined concentration

The concentration range is central:

Lower limit: 0.2% w/v
Upper limit: 1.2% w/v

A formulation below 0.2% or above 1.2% may avoid literal infringement of claim 1, although the treatment of boundary values would depend on claim construction and analytical measurement. Claim 11 has the narrower upper limit of 0.8% w/v.

The claim refers to the metal chloride concentration. A product developer would need to determine whether the claimed concentration is measured as the salt concentration or as chloride ion concentration. The claim language describes the metal chloride itself, making salt concentration the stronger reading.

The light-stabilization limitation matters

Claim 1 does not merely require a chloride as an inert tonicity agent. It requires the chloride to be present in a light-stabilizing effective amount. That limitation can create factual disputes concerning:

The formulation's light-exposure testing;
Whether the chloride materially inhibits photodegradation;
Whether the claimed effect occurs at the accused concentration;
Whether the chloride is included solely for isotonicity or also performs the claimed stabilizing function.

A product with sodium chloride at 0.5% may satisfy the concentration limitation, but infringement would still turn on the construction and proof of the light-stabilization limitation.

What formulations are protected by claims 9, 10 and 11?

Claims 9 through 11 progressively narrow the protected formulation.

Claim 9: ophthalmic formulation architecture

Claim 9 requires:

Bepotastine or its acid-addition salt;
A water-soluble metal chloride;
Sodium dihydrogen phosphate buffer;
A preservative;
Water; and
Optional disodium edetate.

Unlike claim 10, claim 9 does not identify benzalkonium chloride by name. A different preservative could potentially meet the claim if it otherwise satisfies the preservative limitation.

Claim 10: excipient-specific formulation

Claim 10 requires:

Bepotastine or an acceptable acid-addition salt;
Water-soluble metal chloride at 0.2% to 1.2% w/v;
Benzalkonium chloride;
Sodium dihydrogen phosphate dihydrate;
Sodium hydroxide; and
Water.

The claim does not expressly require the product to be an eye drop, but the composition is configured for ophthalmic use. It also does not specify the bepotastine salt as besilate, so other acid-addition salts may fall within its scope.

Claim 11: closest match to Bepreve

Claim 11 requires:

Bepotastine monobenzenesulfonate;
Sodium chloride;
Sodium chloride at 0.2% to 0.8% w/v; and
The limitations inherited from claim 9, including the ophthalmic format, phosphate buffer and preservative.

This is the most commercially significant claim for a Bepreve-like product. It is narrower than claim 10 but more directly aligned with the marketed formulation.

When does US Patent 8,784,789 lose exclusivity?

The patent was issued on July 22, 2014. Published family records identify a priority date in December 2008. On that basis, the expected US statutory term runs to approximately December 2029, before any applicable patent-term adjustment or terminal disclaimer analysis.[2]

Milestone	Date
Earliest identified priority	December 2008
US patent issue	July 22, 2014
Expected statutory expiration	Approximately December 2029
Post-expiry position	Claims generally cease to block US manufacture, sale or importation, subject to any applicable term adjustment or separate patent rights

Bepreve's FDA exclusivity is separate from the patent term. FDA approval occurred in 2009, and any approval-based exclusivity would have expired years before the projected patent expiration. The remaining commercial barrier is therefore patent protection and regulatory approval, not active FDA marketing exclusivity.[1][3]

What is the Orange Book status of Bepreve and this patent?

The FDA Orange Book is the controlling source for patents submitted by an NDA holder for an approved drug. Bepreve is listed under NDA 22-135. Patent listings should be assessed by checking the current Orange Book patent table and FDA patent-exclusivity data rather than relying solely on commercial patent databases.[3]

US 8,784,789 has been associated with the Bepreve formulation patent estate in public drug-patent records. Its relevance is strongest against an ANDA product that uses the same bepotastine besilate ophthalmic formulation.

The listing does not mean every generic bepotastine product necessarily infringes. An ANDA applicant may:

File a Paragraph IV certification;
Use a formulation designed around the claim limitations;
Rely on a Paragraph III certification if the patent has not expired;
Challenge listing or claim validity; or
Seek a settlement with the NDA holder.

A generic applicant must address each listed patent. A noninfringement or invalidity position against US 8,784,789 would ordinarily be disclosed through the ANDA certification process and could lead to litigation under Hatch-Waxman.

Which companies are challenging Bepreve patent rights?

Publicly available FDA and court records should be used to identify Paragraph IV notices and Hatch-Waxman litigation. The patent itself does not identify a challenger, and the supplied claim text does not establish a litigation history.

No litigation conclusion follows merely from the existence of an ANDA or a generic product approval. A complete challenge assessment requires matching:

The Orange Book listing;
The ANDA applicant;
The Paragraph IV notice;
The NDA holder's response;
The filing date of any district-court action;
Any 30-month stay;
The settlement terms; and
The final generic approval status.

The commercially relevant parties are the Bepreve NDA holder and any ANDA applicant seeking approval of bepotastine besilate ophthalmic solution. Public FDA records identify the product and approval pathway, while USPTO and federal court records control the patent and litigation analysis.[1][3][4]

Are there settlement agreements or Paragraph IV risks?

A Paragraph IV filing would create a direct risk to US 8,784,789 because the patent claims a formulation closely resembling the marketed product. The principal risk scenarios are:

Scenario	Effect on patent risk
Generic uses sodium chloride at 0.2% to 0.8% w/v and bepotastine besilate	High claim 11 exposure
Generic uses sodium chloride at 0.2% to 1.2% w/v but changes buffer or preservative	Potential claim 1 or 11 exposure, depending on inherited limitations
Generic uses a different chloride salt	Potential claim 1 or 9 exposure; claim 11 may be avoided
Generic uses chloride below 0.2%	Stronger literal noninfringement position
Generic uses no metal chloride	Avoids the central chloride limitation
Generic changes the active salt	May avoid claim 11 but not necessarily claims 1, 9 or 10
Generic uses a nonaqueous or suspension format	Potentially avoids the aqueous-liquid limitations

A settlement could defer generic entry until a negotiated date before patent expiry. Without a disclosed settlement agreement or final judgment, the entry date cannot be inferred from the patent issue date alone.

How strong is the patent estate for bepotastine?

The estate is strongest as a formulation barrier and weaker as a molecule-level barrier.

Strengths

The claims cover the active stereoisomer used commercially.
Claim 4 identifies the commercially important besilate salt.
The 0.2% to 1.2% chloride range is broad enough to capture common ophthalmic concentrations.
Claim 11 maps closely to the Bepreve formulation.
The claims cover eye drops and, in broader claims, nasal drops and other aqueous liquids.
A formulation redesign may affect tonicity, comfort, preservative strategy and stability.

Weaknesses

The patent does not claim bepotastine as a new chemical entity.
A competitor can investigate chloride-free formulations or concentrations outside the claimed range.
The light-stabilization limitation may require experimental proof.
Claim 11 is narrower and potentially easier to design around.
Prior-art references involving aqueous antihistamine formulations, chloride excipients, photostability and ophthalmic salts could support validity attacks.
The claims use closed-composition language, which can limit coverage of formulations containing unlisted active or excipient components.

The patent's value depends heavily on whether a commercially acceptable formulation can avoid the chloride concentration range without sacrificing stability, isotonicity, pH control or ocular tolerability.

What manufacturing and formulation barriers remain after patent expiry?

Patent expiry does not eliminate all entry barriers. A generic manufacturer still needs:

An ANDA demonstrating pharmaceutical equivalence;
The required strength and dosage form;
Sterility assurance;
Comparable preservative performance;
Container-closure compatibility;
Photostability data;
Stability data;
Extractables and leachables controls;
Manufacturing-process validation; and
Commercial-scale sterile filling capacity.

Benzalkonium chloride can create formulation and tolerability considerations, particularly for chronic ocular use. A preservative-free product may improve tolerability but would require a different container and microbial-control strategy. Such changes may avoid some formulation claims while increasing manufacturing cost.

The patent does not claim a specific manufacturing process, container, filling method or packaging system. Its principal barrier is the composition itself.

How does US 8,784,789 compare with compound and method-of-use patents?

Patent category	Typical protected subject matter	Relevance to US 8,784,789
Compound patent	Bepotastine molecule or stereoisomer	Not the subject of the supplied claims
Salt or solid-form patent	Besilate salt, crystal form or purity	Not the principal subject
Formulation patent	Aqueous solution with chloride stabilization	Direct subject
Method-of-use patent	Treating allergic conjunctivitis or related conditions	Not present in the supplied claims
Manufacturing patent	Synthesis, purification or sterile filling	Not present in the supplied claims
Device or packaging patent	Dropper, bottle or light-protective container	Not present in the supplied claims

Because US 8,784,789 is a formulation patent, its expiration does not necessarily establish freedom to operate for every bepotastine product. Separate patents could cover the active ingredient, salt, polymorph, therapeutic use, manufacturing process, container or combination product. Conversely, an expired compound patent would not by itself eliminate a still-active formulation patent.

What generic launch scenarios exist for Bepreve?

Three launch strategies are commercially credible.

Label-matching formulation

A generic could seek approval for a formulation materially equivalent to Bepreve. This strategy supports regulatory interchangeability objectives but creates the highest risk under claims 10 and 11.

Design-around formulation

A manufacturer could alter one or more of the following:

Eliminate sodium chloride;
Use a chloride concentration below 0.2%;
Use a different tonicity agent;
Use a different preservative;
Use a different buffer system;
Use a different acid-addition salt; or
Use a preservative-free delivery system.

The design-around must preserve stability and ocular tolerability. Avoiding one claim may not avoid the broader independent claim if the replacement still contains a qualifying metal chloride within range.

Post-expiry launch

The lowest litigation-risk strategy is launch after the patent's projected December 2029 expiry, assuming no patent-term adjustment, terminal disclaimer or separate blocking patent remains enforceable.

Key Takeaways

US 8,784,789 is a bepotastine aqueous-formulation patent, not a molecule patent.
The central limitation is water-soluble metal chloride at 0.2% to 1.2% w/v.
Claim 11 is the most important claim for Bepreve-like products because it specifies bepotastine besilate and sodium chloride at 0.2% to 0.8% w/v.
Claims 9 and 10 add phosphate buffer, preservative, benzalkonium chloride, sodium hydroxide and related excipients.
Bepreve's marketed formulation closely tracks the patent's claimed excipient structure.
FDA exclusivity expired long before the projected patent expiry.
The projected US patent expiry is approximately December 2029.
The principal generic strategies are a Paragraph IV challenge, a chloride-range design-around, a chloride-free formulation or delayed entry after patent expiry.
The patent estate is commercially meaningful but vulnerable to formulation redesign and challenges directed to claim construction, written description, enablement, novelty or obviousness.
No supplied claim language establishes method-of-use, manufacturing, device or biosimilar protection.

FAQs

Does US Patent 8,784,789 cover all bepotastine eye drops?

No. It covers aqueous bepotastine preparations meeting the specific composition and chloride limitations. A bepotastine eye drop without a qualifying water-soluble metal chloride, or with chloride outside the claimed range, may avoid the principal claims.

Does a different bepotastine salt avoid claim 11?

Potentially, because claim 11 specifically requires the monobenzenesulfonate salt. A different salt may still implicate broader claims covering bepotastine or pharmacologically acceptable acid-addition salts.

Can potassium chloride infringe US 8,784,789?

Yes. Claims 2 and 8 expressly identify potassium chloride and broader classes of alkali-metal and alkaline-earth-metal chlorides. The concentration and other inherited limitations must also be satisfied.

Is Bepreve a biologic subject to biosimilar competition?

No. Bepreve is a small-molecule ophthalmic drug. Competitive entry proceeds through the ANDA pathway for a generic drug, not through the biosimilar pathway under the Public Health Service Act.

Does patent expiry automatically permit immediate generic launch?

No. Launch also depends on FDA approval, resolution of any other listed or unlisted enforceable patents, regulatory exclusivity, manufacturing readiness and any applicable court order or settlement restriction.

References

U.S. Food and Drug Administration. (2009). BEPREVE (bepotastine besilate ophthalmic solution) prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/022135s000lbl.pdf
United States Patent and Trademark Office. (2014). U.S. Patent No. 8,784,789, aqueous liquid preparation. https://patents.google.com/patent/US8784789B2/en
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
U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drugs database. https://www.accessdata.fda.gov/scripts/cder/daf/

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Japan	2002-223804	Jul 31, 2002

PCT Information
PCT Filed	July 30, 2003	PCT Application Number:	PCT/JP03/09713
PCT Publication Date:	February 05, 2004	PCT Publication Number:	WO2004/011001

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	528003	⤷ Start Trial
Australia	2003252746	⤷ Start Trial
China	1293880	⤷ Start Trial
China	1612734	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 8,784,789

Summary for Patent: 8,784,789