Last updated: September 24, 2026
Sun Pharmaceutical Industries, Inc. sued Perrigo Company in the U.S. District Court for the District of Delaware in 2018 under the Hatch-Waxman Act. The case concerned Perrigo’s abbreviated new drug application for a generic version of Sun’s BromSite ophthalmic product, a bromfenac sodium ophthalmic solution used to treat inflammation and prevent ocular pain after cataract surgery. The dispute was an ANDA patent case rather than a product-liability or antitrust action.
The case ended without a publicly reported merits decision establishing invalidity or noninfringement. The docket reflects resolution by stipulated dismissal, consistent with a confidential settlement. The public record does not establish Perrigo’s authorized launch date or the complete commercial terms.
What drug and FDA application were involved in Sun v. Perrigo?
The dispute involved BromSite, an ophthalmic solution containing bromfenac sodium at a 0.075% concentration. Sun markets BromSite for the treatment of postoperative ocular inflammation and prevention of ocular pain in patients undergoing cataract surgery.
| Item |
Information |
| Brand |
BromSite |
| Active ingredient |
Bromfenac sodium |
| Dosage form |
Ophthalmic solution |
| Strength |
0.075% |
| Reference sponsor |
Sun Pharmaceutical Industries, Inc. |
| Regulatory pathway |
ANDA litigation under Hatch-Waxman |
| Defendant |
Perrigo Company |
| Court |
U.S. District Court for the District of Delaware |
| Civil action |
1:18-cv-00703 |
| Case type |
Abbreviated New Drug Application patent infringement action |
Perrigo’s ANDA filing triggered Sun’s patent-infringement claims under 35 U.S.C. § 271(e)(2). That provision treats the filing of an ANDA seeking approval for a patented drug as an artificial act of infringement for purposes of resolving patent disputes before generic marketing.
BromSite’s commercial value comes from its formulation and dosing profile. Unlike a conventional bromfenac ophthalmic product, BromSite uses a formulation designed to provide a 0.075% concentration and support postoperative dosing. The litigation therefore focused on formulation and method-of-use rights rather than a broad chemical-composition patent on bromfenac itself.
What patents protect BromSite?
Sun’s BromSite patent estate included formulation and treatment patents listed in the FDA’s Orange Book or otherwise asserted in litigation involving generic bromfenac ophthalmic products. Publicly reported BromSite patent listings included patents in the following families:
| Patent family |
General subject matter |
Commercial relevance |
| U.S. Patent No. 8,859,623 |
Bromfenac ophthalmic compositions and delivery characteristics |
Formulation protection |
| U.S. Patent No. 9,278,096 |
Ophthalmic bromfenac treatment methods |
Method-of-use protection |
| U.S. Patent No. 9,675,653 |
Bromfenac ophthalmic treatment and dosing technology |
Method-of-use or formulation protection |
| Related continuation patents |
Formulation, dosing, and postoperative treatment claims |
Potentially extended patent coverage |
Patent scope and listing status can change as continuation applications issue, patents expire, or FDA listings are updated. The asserted patents in a specific ANDA case must be determined from the complaint, infringement contentions, and docket filings rather than from the product label alone.
The estate’s principal defensive value was its ability to combine formulation claims with method-of-use claims. A generic applicant might avoid a formulation claim by designing around a particular excipient or manufacturing parameter, but a method-of-use claim can create a separate obstacle if the proposed label instructs use for cataract-surgery patients.
When does BromSite lose patent exclusivity?
BromSite did not have a single exclusivity date. Its commercial protection depended on several separate patent families, regulatory exclusivity, and the outcome of generic litigation.
Patent exclusivity
The earliest BromSite patents were expected to expire before later-issued continuation patents. Patent-term adjustment, patent-term extension, terminal disclaimers, and maintenance status affect the actual expiration date of each patent.
The relevant commercial analysis is therefore based on the latest enforceable patent covering the generic product or its labeled use. Publicly available patent records indicate that later BromSite patents could extend into the late 2020s or early 2030s, depending on the specific patent and claim scope.
FDA exclusivity
BromSite’s FDA exclusivity was separate from patent protection. New-drug exclusivity may have restricted FDA approval of an ANDA for a defined period, but it would not prevent a generic applicant from filing an ANDA or initiating patent litigation. The practical launch date depended primarily on patent settlement terms and the Orange Book-listed patents.
What was Perrigo’s Paragraph IV challenge?
Perrigo’s ANDA certification placed the case within the Paragraph IV framework. A Paragraph IV certification asserts that an Orange Book-listed patent is invalid, unenforceable, or will not be infringed by the proposed generic product.
Sun’s lawsuit was the statutory response to that certification. Filing the action within 45 days of receiving Perrigo’s notice triggered the Hatch-Waxman 30-month stay under 21 U.S.C. § 355(j)(5)(B)(iii), unless the stay was shortened or terminated by a court order or settlement.
The case did not produce a public trial judgment resolving whether Perrigo’s product infringed the asserted BromSite claims. The absence of a merits decision means the docket does not establish that the patents were valid, that Perrigo’s ANDA product infringed, or that Perrigo’s noninfringement or invalidity arguments failed.
What was the litigation timeline?
| Date or period |
Event |
| 2018 |
Sun filed the patent-infringement action in the District of Delaware after receiving Perrigo’s ANDA notice |
| 2018-2019 |
Pleadings, ANDA-related discovery, and claim-construction activity proceeded under the Hatch-Waxman framework |
| Later period |
The parties resolved the dispute without a reported merits judgment |
| Case closure |
The action was dismissed by stipulation |
The public docket does not provide a judicial opinion holding the asserted patents invalid or infringed. The resolution therefore has limited precedential value for other BromSite cases, although settlement terms may have affected Perrigo’s launch rights.
What was the settlement between Sun and Perrigo?
The public record indicates that the dispute ended through a stipulated dismissal. The parties did not publicly disclose the material commercial terms.
A Hatch-Waxman settlement can include:
- An agreed generic launch date;
- A license to market an authorized or independent generic;
- A covenant not to sue;
- Restrictions on formulation or labeling;
- Supply arrangements;
- Allocation of litigation costs; or
- A contingent launch right tied to other patent litigation.
The docket does not establish which of these terms applied. No public record identified a litigated finding that the settlement was anticompetitive or an unlawful reverse-payment agreement.
What was the FDA and Orange Book status?
BromSite was FDA-approved as a prescription ophthalmic product. The Orange Book listed patents associated with the reference product, giving Sun the ability to receive notice of a Paragraph IV certification and bring an infringement action.
The Orange Book did not itself determine:
- Whether a patent claim was valid;
- Whether Perrigo’s proposed product infringed;
- Whether a patent covered every possible generic formulation;
- Whether Perrigo could launch after settlement; or
- Whether the patent remained commercially valuable after a covenant not to sue.
Those issues were controlled by the patent claims, FDA application details, court orders, and settlement documents.
Because BromSite is a small-molecule ophthalmic drug, biosimilar rules did not apply. A competing applicant would use the ANDA pathway rather than the Biologics Price Competition and Innovation Act pathway.
How strong was Sun’s BromSite patent estate?
Sun’s patent position was stronger than a single-patent estate but narrower than a broad active-ingredient monopoly.
Strengths
The estate had several commercial advantages:
- It covered a differentiated ophthalmic formulation rather than only bromfenac as a molecule.
- It could combine formulation claims with postoperative treatment claims.
- The reference product’s FDA-approved label could support method-of-use infringement theories.
- A generic applicant might face design-around and labeling constraints.
- Orange Book listing enabled a prelaunch patent challenge and 30-month stay.
Weaknesses
The estate also had litigation vulnerabilities:
- Formulation claims can be attacked with prior-art references covering bromfenac ophthalmic solutions.
- Method-of-use claims may be vulnerable to a proposed label that carves out patented indications or dosing instructions.
- Patent expiration dates were staggered, creating a risk that an early patent would expire before the later patents could sustain a launch bar.
- ANDA defendants can challenge written description, enablement, anticipation, obviousness, and claim-construction issues.
- A confidential settlement prevents market participants from determining how the parties assessed trial risk.
The absence of a merits ruling leaves patent strength commercially unresolved. Sun secured a negotiated outcome, but the settlement does not validate the asserted patents.
What generic entry risks existed?
Generic entry risk depended on the settlement’s launch provisions and the enforceability of the remaining patents.
Immediate launch
An immediate or early Perrigo launch could have reduced BromSite’s price and market share, particularly because ophthalmic products are often substitutable at the pharmacy and payer level. Sun’s exposure would have been higher if Perrigo had a first-filer position or if other ANDA applicants could rely on the same patent resolution.
Delayed launch
A delayed-entry settlement would preserve branded pricing for the agreed period but would not eliminate later competition. Other generic applicants could still challenge the patents or enter after expiration.
At-risk launch
An at-risk launch would have exposed Perrigo to damages and possible injunctive relief if Sun prevailed on an enforceable patent. The financial risk would have depended on BromSite sales, the duration of infringement, and whether Sun could prove lost profits or obtain a reasonable royalty.
How did BromSite compare with competing ophthalmic products?
BromSite competed with other postoperative nonsteroidal anti-inflammatory ophthalmic products, including generic bromfenac products and branded products containing nepafenac or ketorolac.
| Product category |
Active ingredient |
Patent profile |
Generic risk |
| BromSite |
Bromfenac sodium 0.075% |
Formulation and method-of-use patents |
Dependent on Orange Book patents and settlement |
| Generic bromfenac |
Bromfenac sodium, varying strengths |
Usually subject to separate product and use claims |
High after relevant patents expire or are licensed |
| Nevanac/Ilevro |
Nepafenac |
Separate formulation and method patents |
Product-specific litigation |
| Acular and generics |
Ketorolac tromethamine |
Older active ingredient and formulation estate |
Mature generic competition |
BromSite’s differentiation was tied to the 0.075% formulation and postoperative use. That differentiation could support branded pricing, but it also concentrated patent risk in formulation and dosing claims.
What is the commercial impact of the case?
The case presented a direct risk to Sun’s ophthalmic franchise. BromSite revenue could be affected by:
- The timing of Perrigo’s authorized launch;
- The number of additional ANDA applicants;
- Payer substitution policies;
- Wholesale acquisition price reductions;
- Sun’s ability to preserve premium pricing;
- Patent settlements with other generic companies; and
- The enforceability of later-issued continuation patents.
The public docket does not disclose BromSite revenue attributable to the Perrigo dispute or any settlement payment. A precise revenue-at-risk calculation cannot be derived from the case record alone.
Key Takeaways
- Sun v. Perrigo, 1:18-cv-00703, was a Hatch-Waxman action involving Perrigo’s proposed generic BromSite.
- BromSite contains bromfenac sodium 0.075% in an ophthalmic solution.
- Sun relied on formulation and method-of-use patent protection rather than a basic bromfenac molecule patent.
- Perrigo’s Paragraph IV certification triggered the litigation and the statutory 30-month stay framework.
- The case ended through stipulated dismissal without a public merits decision.
- The settlement terms and Perrigo’s authorized launch date were not publicly disclosed.
- No biosimilar pathway was involved because BromSite is a small-molecule drug.
- The case provides limited precedent on patent validity or infringement because the parties settled.
FAQs
Did Sun win the BromSite patent case against Perrigo?
No public merits judgment established a Sun victory. The case was resolved through stipulated dismissal, which indicates settlement but does not determine patent validity or infringement.
Could Perrigo launch a generic version of BromSite?
The public docket does not establish the precise launch date or settlement restrictions. Perrigo’s ability to launch depended on the confidential settlement and the surviving Orange Book patents.
Was BromSite protected by a composition-of-matter patent?
The commercial dispute centered primarily on ophthalmic formulation and method-of-use protection. The key protection was not a broad monopoly over bromfenac as an active ingredient.
Does Sun v. Perrigo affect other generic bromfenac products?
The case may have commercial relevance to other ANDA applicants, but a confidential settlement and absence of a merits opinion limit its precedential value. Other applicants would still face product-specific patent and label analysis.
Was the case related to a biosimilar challenge?
No. BromSite is a small-molecule ophthalmic drug. Any competing product would generally proceed through the ANDA pathway rather than the biosimilar pathway.
References
-
U.S. District Court for the District of Delaware. (2018). Sun Pharmaceutical Industries, Inc. v. Perrigo Company, No. 1:18-cv-00703. PACER docket.
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U.S. Food and Drug Administration. (n.d.). BromSite (bromfenac sodium ophthalmic solution) prescribing information. FDA.
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U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations. FDA Orange Book.
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U.S. Patent and Trademark Office. (n.d.). Patent Center and Patent Examination Data System records for U.S. Patent Nos. 8,859,623, 9,278,096, and 9,675,653. USPTO.
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Hatch, Waxman, and Drug Price Competition and Patent Term Restoration Act, 21 U.S.C. § 355(j); 35 U.S.C. § 271(e)(2).
