Last updated: August 4, 2026
Alcon sued Padagis Israel Pharmaceuticals Ltd. in the U.S. District Court for the District of Delaware after Padagis filed an abbreviated new drug application seeking approval for a generic version of Pazeo, Alcon’s olopatadine hydrochloride ophthalmic solution, 0.7%. The case was a Hatch-Waxman patent action under 35 U.S.C. § 271(e)(2). Alcon asserted U.S. Patent Nos. 8,598,172 and 9,066,856, which covered ophthalmic compositions containing olopatadine. The case was resolved without a reported trial judgment, and the docket was later closed following settlement-related dismissal activity. [1][2]
What drug and patents were involved in Alcon v. Padagis?
The dispute concerned Pazeo, an ophthalmic solution containing olopatadine hydrochloride at a concentration of 0.7%. Pazeo was approved by the FDA under NDA No. 205650 for the treatment of ocular itching associated with allergic conjunctivitis. [3]
| Item |
Details |
| Reference drug |
Pazeo |
| Active ingredient |
Olopatadine hydrochloride |
| Strength |
0.7% ophthalmic solution |
| Dosage form |
Topical ophthalmic solution |
| NDA holder |
Alcon Laboratories Inc. |
| NDA number |
205650 |
| Litigation court |
U.S. District Court for the District of Delaware |
| Case number |
1:22-cv-01422 |
| Complaint date |
2022 |
| Statutory basis |
Hatch-Waxman, 35 U.S.C. § 271(e)(2) |
| Defendant |
Padagis Israel Pharmaceuticals Ltd. |
| Asserted patents |
U.S. Patent Nos. 8,598,172 and 9,066,856 |
The complaint followed Padagis’ Paragraph IV notice to Alcon. By making a Paragraph IV certification, Padagis represented that the listed patents were invalid, unenforceable, or would not be infringed by the proposed generic product. [1]
What patents protected Pazeo and what did they cover?
Alcon asserted two composition patents directed to ophthalmic formulations containing olopatadine.
U.S. Patent No. 8,598,172
U.S. Patent No. 8,598,172 addressed ophthalmic compositions containing olopatadine and formulation components intended to provide an effective, tolerable treatment for allergic eye disease. The patent was assigned to Alcon and had an expiration date in late 2029, subject to any applicable patent-term adjustment or extension reflected in the official patent record. [4]
The commercial relevance of the patent was its coverage of the formulation rather than the broad discovery of olopatadine as an antihistamine. The asserted claims were directed to specific ophthalmic composition parameters, including olopatadine concentration and excipient characteristics.
U.S. Patent No. 9,066,856
U.S. Patent No. 9,066,856 was a related Alcon patent covering ophthalmic compositions containing olopatadine. It was also listed in connection with Pazeo and had a patent term extending into 2029. [2][5]
The two patents created overlapping protection around the commercial formulation. In a Hatch-Waxman case, that overlap can increase the cost of a Paragraph IV challenge because the generic applicant must prevail against each asserted patent or obtain a settlement permitting a defined launch date.
When did Pazeo lose exclusivity?
Pazeo’s FDA exclusivity and patent protection had different timelines.
| Protection |
Relevant date or period |
| FDA approval of Pazeo |
2015 |
| New chemical entity exclusivity |
Not available because olopatadine had previously been approved |
| Listed patent protection |
Extended into 2029 |
| Paragraph IV litigation |
Filed in 2022 |
| Potential statutory stay |
Up to 30 months from receipt of the Paragraph IV notice, subject to statutory exceptions |
| Generic entry |
Governed by the settlement and FDA approval status |
Pazeo did not receive five-year new chemical entity exclusivity because olopatadine had already been approved in earlier products, including Patanol and Pataday formulations. Its principal remaining barrier was patent protection, not NCE exclusivity. [3][6]
The 30-month stay under 21 U.S.C. § 355(j)(5)(B)(iii) would have delayed FDA approval of Padagis’ ANDA unless the litigation ended earlier, the court entered a judgment, or another statutory exception applied. The precise stay calculation depends on the date Alcon received Padagis’ Paragraph IV notice and the procedural record.
What was the Paragraph IV challenge in Alcon v. Padagis?
Padagis’ ANDA included a Paragraph IV certification against Alcon’s listed Pazeo patents. The certification created the statutory act of infringement that permitted Alcon to file suit before commercial marketing of the generic product.
The central legal issues were expected to include:
- Whether the proposed Padagis formulation fell within the asserted composition claims.
- Whether the asserted claims were invalid for anticipation or obviousness.
- Whether the patents were unenforceable because of inequitable conduct or other equitable defenses.
- Whether the asserted claims were adequately tied to the formulation described in the ANDA.
- Whether Padagis’ proposed product could be approved and marketed before the listed patent expiration dates.
The case did not produce a reported merits opinion determining validity or infringement. That limits the precedential value of the dispute. The settlement outcome, rather than a judicial claim-construction or invalidity ruling, determined the commercial effect.
What was the litigation status and how did the case end?
The action proceeded as a standard Delaware ANDA case. Alcon filed the complaint after receiving Padagis’ Paragraph IV notice. The parties later resolved the dispute, and the case was closed through dismissal filings rather than a public trial verdict. [1]
No reported decision established that either asserted patent was invalid or not infringed. There also was no reported finding of willful infringement, inequitable conduct, or antitrust liability.
The settlement terms were not publicly disclosed in the docket materials typically available for this type of dismissal. As a result, the public record does not establish the agreed generic launch date, any launch acceleration provisions, royalty terms, supply arrangements, or restrictions on authorized generic competition.
Settlement implications
A settlement in an ANDA case can include:
- A permitted-entry date before patent expiration.
- A later entry date tied to one or more patent expirations.
- A license covering the asserted patents.
- A covenant not to sue.
- An authorized-generic arrangement.
- Manufacturing or supply provisions.
- Acceleration provisions if another generic entrant obtains an earlier launch right.
The dismissal confirms that the litigation ended, but it does not by itself reveal which commercial provisions the parties adopted. The absence of a public merits judgment means the case should not be treated as a judicial validation of Alcon’s patent claims.
What was the Orange Book status of Pazeo?
Pazeo was listed in the FDA Orange Book as an approved olopatadine ophthalmic solution. The relevant patent listings included Alcon patents directed to the drug’s formulation. [2]
Orange Book listing gives the NDA holder a mechanism to trigger Hatch-Waxman litigation when an ANDA applicant files a Paragraph IV certification. It does not establish that the listed patent will survive an invalidity challenge. It also does not prevent an ANDA applicant from filing a Paragraph III certification, although a Paragraph III certification generally defers approval until patent expiration.
The Pazeo dispute illustrates the commercial importance of formulation patents. Olopatadine itself was an established active ingredient. Alcon’s patent position instead depended on claims directed to the particular 0.7% ophthalmic formulation and its composition parameters.
How strong was Alcon’s Pazeo patent estate?
Alcon’s patent estate was commercially meaningful but narrower than a new chemical entity patent estate.
Strengths
The estate had several advantages:
- It covered the approved Pazeo formulation rather than only a broad therapeutic use.
- The listed patents extended into 2029.
- Two related patents increased the number of barriers a generic applicant had to address.
- The patents were listed in the Orange Book, enabling Hatch-Waxman enforcement.
- The product had a defined commercial formulation that could be compared against the ANDA.
Limitations
The estate also had structural limitations:
- Olopatadine was an established active ingredient.
- The patents were formulation-focused and therefore potentially vulnerable to claim-scope and obviousness arguments.
- A generic applicant could seek approval by designing around claimed excipient, concentration, or formulation limitations.
- The 0.7% olopatadine market had other commercial products and substitution risks.
- A settlement could permit entry materially before the nominal 2029 patent expiration.
The absence of a merits decision leaves the ultimate validity and infringement strength unresolved. The patents should therefore be viewed as effective litigation assets during the settlement period, but not as patents whose validity was confirmed by the court.
Which companies were challenging Alcon’s Pazeo patents?
Padagis was the defendant in this case. The company develops and markets generic and specialty pharmaceutical products and had an ANDA strategy directed at the Pazeo formulation.
Other generic manufacturers may have pursued olopatadine ophthalmic products under separate ANDAs or different strengths, including 0.1% and 0.2% products. Those products do not necessarily present the same patent issues as a 0.7% Pazeo generic. Product strength, formulation composition, preservative system, and Orange Book certifications determine whether a separate ANDA triggers the same patent claims.
The case should therefore be distinguished from litigation involving Patanol or Pataday formulations. Those products contain olopatadine but are not interchangeable for patent-analysis purposes.
What generic launch risks existed for Pazeo?
The principal generic-entry risks were:
| Risk |
Business impact |
| Paragraph IV settlement |
Could authorize Padagis entry before 2029 |
| Formulation design-around |
Could permit approval without infringing all asserted claims |
| Multiple ANDA applicants |
Could accelerate price erosion |
| OTC and prescription substitution |
Could reduce branded Pazeo retention |
| Limited formulation differentiation |
Could increase pharmacy substitution |
| Settlement disclosure limits |
Makes launch timing difficult to determine from public filings |
The largest commercial uncertainty was the settlement launch date. If Padagis received a license for entry before patent expiration, Alcon could face price erosion and share loss before 2029. If the settlement deferred entry until near patent expiry, Alcon would retain a longer period of formulation exclusivity.
The practical impact also depended on whether Padagis obtained a first-filer position. A first applicant with a qualifying Paragraph IV certification may receive 180-day generic exclusivity under the FDCA. The public case record does not establish that Padagis held an operative first-filer exclusivity position or that it obtained a 180-day exclusivity period.
Did biosimilar risk apply to Pazeo?
No. Pazeo is a small-molecule drug, not a biologic. Biosimilar provisions under the Biologics Price Competition and Innovation Act do not apply. The relevant competitive pathway was an ANDA under the Hatch-Waxman Act.
The competitive risks were ordinary generic risks: Paragraph IV litigation, formulation design-around, settlement-based entry, and post-approval substitution.
How did Alcon’s Pazeo estate compare with a biologic patent estate?
Alcon’s Pazeo estate was narrower and more expiration-driven than a typical biologic estate.
| Factor |
Pazeo |
Biologic reference product |
| FDA pathway |
ANDA |
Biologics license and biosimilar application |
| Active ingredient |
Small molecule |
Biologic |
| Main challenge |
Paragraph IV |
Biosimilar or patent litigation |
| Orange Book |
Applicable |
Generally not the primary listing system |
| Substitution |
Pharmacy substitution may apply |
State-law and interchangeability rules matter |
| Key patent risk |
Formulation and method claims |
Composition, formulation, process, and manufacturing claims |
| Regulatory exclusivity |
Drug exclusivity rules |
Biologic exclusivity rules |
Pazeo did not benefit from biologic reference-product exclusivity. Its defense depended on the listed formulation patents and the commercial terms of the litigation settlement.
What revenue exposure did the case create for Alcon?
The case exposed Alcon’s Pazeo revenue to generic erosion. The public litigation docket does not provide a verified product-level revenue figure for Pazeo, so the case value cannot be quantified from the complaint alone.
Revenue exposure depended on:
- Pazeo prescription volume at the time of generic approval.
- The negotiated Padagis launch date.
- The number of other approved olopatadine products.
- The degree of pharmacy substitution.
- Any authorized-generic or supply arrangement.
- Alcon’s ability to shift demand to Pataday or other allergy products.
Because olopatadine was available in multiple strengths and brands, Pazeo faced substitution risk independent of the litigation. The case primarily protected the 0.7% formulation and did not create broad exclusivity over all olopatadine ophthalmic products.
Key Takeaways
- Alcon sued Padagis in Delaware over an ANDA for generic Pazeo, a 0.7% olopatadine hydrochloride ophthalmic solution.
- The asserted patents were U.S. Patent Nos. 8,598,172 and 9,066,856.
- The patents were formulation patents with terms extending into 2029.
- Padagis filed a Paragraph IV challenge, triggering Hatch-Waxman litigation.
- The case ended through settlement-related dismissal without a reported validity or infringement ruling.
- Public filings do not establish the settlement’s generic launch date or commercial terms.
- Pazeo had no biosimilar risk because it is a small-molecule drug.
- Alcon’s principal exposure was generic price erosion after any settlement-authorized Padagis launch.
FAQs About Alcon v. Padagis
Did Alcon win the patent case against Padagis?
The docket does not show a reported trial judgment or merits ruling for Alcon. The parties resolved the litigation through settlement-related dismissal.
What generic drug did Padagis seek to market?
Padagis sought FDA approval for a generic olopatadine hydrochloride ophthalmic solution corresponding to Pazeo, including the 0.7% strength at issue in the litigation.
Did the settlement allow Padagis to launch before 2029?
The public record does not disclose the settlement’s launch date. The nominal patent expirations do not establish the actual agreed entry date.
Are Pazeo and Pataday covered by the same patents?
They contain the same active ingredient, olopatadine, but have different formulations, strengths, regulatory histories, and patent listings. Patent coverage must be assessed product by product.
Could another generic company challenge the same Pazeo patents?
Yes. A separate ANDA applicant could file its own Paragraph IV certification or pursue a design-around formulation. Any later challenge would depend on the applicant’s formulation and the patents listed for the relevant NDA.
References
-
Alcon Inc. v. Padagis Israel Pharmaceuticals Ltd., No. 1:22-cv-01422, U.S. District Court for the District of Delaware, docket filings and complaint (2022-2024).
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U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, Orange Book: Pazeo and NDA No. 205650.
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U.S. Food and Drug Administration. (2015). Pazeo prescribing information and approval materials, NDA No. 205650.
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U.S. Patent and Trademark Office. (2009-2029). U.S. Patent No. 8,598,172, patent and assignment records.
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U.S. Patent and Trademark Office. (2016-2029). U.S. Patent No. 9,066,856, patent and assignment records.
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Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 355(j), abbreviated new drug applications and patent certifications.
