Litigation Details for Silvergate Pharmaceuticals Inc. v. Bionpharma Inc. (D. Del. 2016)

Silvergate Pharmaceuticals Inc. v. Bionpharma Inc. (D. Del. 2016)

Docket		Date Filed	2016-09-28
Court	District Court, D. Delaware	Date Terminated	2018-10-05
Cause	35:271 Patent Infringement	Assigned To	Mitchell S. Goldberg
Jury Demand	None	Referred To
Parties	BIONPHARMA INC.; SILVERGATE PHARMACEUTICALS INC.
Patents	6,028,222; 6,977,257; 7,758,890; 8,568,747; 8,685,460; 8,778,366; 9,855,214; 9,968,553
Attorneys	Douglas H. Carsten; Kenneth Laurence Dorsney
Firms	Morris, Nichols, Arsht & Tunnell
Link to Docket	External link to docket

Details for Silvergate Pharmaceuticals Inc. v. Bionpharma Inc. (D. Del. 2016)

Date Filed	Document No.	Description	Snippet	Link To Document
2016-09-28				External link to document
2016-09-28	147		pertaining to U.S. Patent Nos. 8,568,747 (the “’747 patent”) and 8,778,366 (the “’366 patent”) (collectively…matter of the Patents-in-Suit or any patents or patent applications related to the Patents-in-Suit ….” …Fed. Cir. 2007). The faces of the patents-in-suit, and the U.S. Patent and Trademark Office’s electronic… Production of Assignments and Licenses of the Patents-In-Suit - filed by Bionpharma Inc.. (Attachments… PRODUCTION OF ASSIGNMENTS AND LICENSES OF THE PATENTS-IN-SUIT Defendant Bionpharma Inc. (“Defendant	External link to document
2016-09-28	198		U.S. Patent No. 8,568,747 (“the ’747 Patent”) and U.S. Patent No. 8,778,366 (“the ’366 Patent”), has…include a third patent. While this patent will be litigated with the ’747 and the ’366 Patents, because claim…address only Column 19 of the ’747 Patent, the ’747 Patent and ’366 Patent share a common specification. I…of seven terms contained in the ’747 Patent and the ’366 Patent’s claims.2 1 On May 18, 2017, Chief… before the expiration of the ’747 Patent. The ’366 Patent was issued to the same inventors on	External link to document
2016-09-28	215		judgment of non-infringement of U.S. Patent Nos. 8,568,747 B2 and 8,778,366 B2 - re 214 Order,,. (Dorsney, …2016 5 October 2018 1:16-cv-00876 830 Patent None District Court, D. Delaware	External link to document
2016-09-28	219		non-infringement of U.S. Pat ent Nos. 8,568,747 B2 and 8,778,366 B2 by Bionpharma Inc.. (Dorsney, Kenneth) (Entered…2016 5 October 2018 1:16-cv-00876 830 Patent None District Court, D. Delaware	External link to document

Silvergate Pharmaceuticals Inc. v. Bionpharma Inc.: A Comprehensive Litigation Summary and Analysis

Case Overview

The case of Silvergate Pharmaceuticals Inc. v. Bionpharma Inc. involves a patent infringement dispute centered around the generic version of the drug Epaned® (enalapril maleate), an angiotensin converting enzyme (ACE) inhibitor used to treat hypertension and other cardiovascular conditions. Here is a detailed summary and analysis of the key points in this litigation.

Background and Parties Involved

Silvergate Pharmaceuticals Inc., a subsidiary of Azurity Pharmaceuticals, Inc., is the plaintiff in this case. Bionpharma Inc., a company involved in developing, manufacturing, and selling generic pharmaceutical products, is the defendant. The case was heard in the United States District Court for the District of Delaware[1][4].

Patents-in-Suit and Drug Product

The patents at issue are U.S. Patent Nos. 10,039,745 (the ’745 patent) and 10,153,987 (the ’987 patent), which claim enalapril formulations for Epaned. Bionpharma filed an Abbreviated New Drug Application (ANDA) seeking to market and sell a generic version of Epaned, prompting Silvergate to sue for patent infringement[1][4].

Nature of the Case and Issues Presented

Silvergate alleged that Bionpharma’s generic product infringed on the patents-in-suit under the doctrine of equivalents, as Bionpharma’s product did not literally infringe the claims of the patents. The central issues revolved around two claim limitations: the buffer limitation and the preservative limitation[1][4].

Buffer Limitation

The buffer limitation required the presence of “a buffer comprising about 0.8 to about 3.5 mg/ml of citric acid and about 0.1 to about 0.8 mg/ml sodium citrate.” Bionpharma’s generic product did not contain citric acid or sodium citrate. Silvergate argued that certain compounds in the generic product were equivalent to the claimed buffer. However, the court rejected this argument based on prosecution-history estoppel. During patent prosecution, Silvergate had amended its claims to include specific concentrations of citric acid and sodium citrate, which the court found to be a narrowing amendment that surrendered all equivalents within the territory between the original claim and the amended claim[1][4].

Preservative Limitation

The preservative limitation required “about 0.7 to about 1.2 mg/mL sodium benzoate.” Bionpharma’s generic product did not contain sodium benzoate. Silvergate argued that the generic product infringed under the doctrine of equivalents, but the court rejected this argument based on the disclosure-dedication doctrine. The court found that Silvergate had dedicated the embodiment in Bionpharma’s generic product to the public, as it was described in the patent specification but not claimed[1][4].

Court Findings and Conclusions

After a five-day bench trial, the court concluded that:

• Silvergate was barred by prosecution history estoppel from asserting doctrine of equivalents (DOE) infringement of the buffer limitation.
• Silvergate failed to prove that Bionpharma’s proposed product contained an equivalent to the buffer of the claims.
• Silvergate disclosed and dedicated to the public the accused equivalent of the preservative limitation[1][4].

Impact of the Decision

The decision in this case highlights the importance of careful claim drafting and the implications of amendments made during patent prosecution. It also underscores the limitations imposed by the doctrine of equivalents and the disclosure-dedication doctrine in patent infringement cases.

Key Takeaways

• Prosecution History Estoppel: Amendments made during patent prosecution can significantly limit the scope of what can be claimed under the doctrine of equivalents.
• Disclosure-Dedication Doctrine: Embodiments described in the patent specification but not claimed are dedicated to the public and cannot be asserted as equivalents.
• Claim Limitations: Specific claim limitations, such as those related to buffers and preservatives, must be carefully considered to avoid narrowing amendments that surrender equivalents.

FAQs

Q: What was the main issue in the Silvergate Pharmaceuticals Inc. v. Bionpharma Inc. case?

A: The main issue was whether Bionpharma’s generic version of Epaned infringed on Silvergate’s patents under the doctrine of equivalents.

Q: What are the key claim limitations in this case?

A: The key claim limitations were the buffer limitation and the preservative limitation.

Q: Why did the court reject Silvergate’s argument on the buffer limitation?

A: The court rejected the argument based on prosecution-history estoppel, as Silvergate had made narrowing amendments during patent prosecution that surrendered all equivalents.

Q: What is the disclosure-dedication doctrine, and how did it apply in this case?

A: The disclosure-dedication doctrine states that embodiments described in the patent specification but not claimed are dedicated to the public. In this case, it applied to the preservative limitation, as Silvergate had described but not claimed the embodiment used in Bionpharma’s generic product.

Q: What was the outcome of the bench trial in this case?

A: The court found that Bionpharma’s generic product did not infringe on Silvergate’s patents, both literally and under the doctrine of equivalents.

Cited Sources

1. JD Supra, Silvergate Pharms. Inc. v. Bionpharma Inc., https://www.jdsupra.com/legalnews/silvergate-pharms-inc-v-bionpharma-inc-3621058/
2. CCH Business, IN THE UNITED STATES DISTRICT COURT FOR THE DISTRICT ..., https://business.cch.com/ipld/SilvergateBionpharma20210429.pdf
3. PharmaCompass, NOVARTIS PHARMACEUTICALS CORPORATION Plaintiff, v ..., https://www.pharmacompass.com/pdf/news/gilenya-fingolimod-novartis-pharmaceuticals-corporation-v-accord-healthcare-inc-et-al-1532017908.pdf