Merck Sharp & Dohme Corp. v. Ajanta Pharma Limited et al.

I'll research this case across dockets, court records, and industry sources.

Good initial hits. Let me dig deeper into the MDL, the stipulation, PTAB proceedings, and the settlement.

Let me pin down the Ajanta-specific disposition and the outcome of the parallel IPR/appeals.

Overview & Background

Parties. Merck Sharp & Dohme Corp. is the plaintiff — a U.S. operating subsidiary of Merck & Co., Inc. (NYSE: MRK), the innovator/originator manufacturer that markets Januvia, Janumet, and Janumet XR. Its Rule 7.1 disclosure in this case identifies Merck & Co., Inc. as its parent (docket, June 2020). The defendants are Ajanta Pharma Limited, a Mumbai-based Indian generic manufacturer (no parents/affiliates listed in its Rule 7.1 disclosure), and its U.S. marketing affiliate Ajanta Pharma USA Inc. This is therefore a classic innovator-vs.-generic Hatch-Waxman dispute, not an NPE/PAE assertion: Merck is asserting its own commercial patent to block a generic competitor's ANDA. Ajanta is a pure generic filer here and appears in FDA records as the applicant on sitagliptin ANDA No. 214784 (25/50/100 mg tablets) and on a sitagliptin/metformin ANDA (No. 216516), both of which FDA records list with tentative rather than final approval — consistent with the '708 patent's Orange Book listing through May 24, 2027.

Patents and accused product. The sole patent asserted in this action is U.S. Patent No. 7,326,708, titled "Phosphoric acid salt of a dipeptidyl peptidase-IV inhibitor" (Cypes et al.; assigned to Merck; issued Feb. 5, 2008, from a June 2003 priority filing). Claim 1 covers the dihydrogenphosphate (DHP) salt of sitagliptin — the DPP-4 inhibitor that is the active moiety in Januvia/Janumet — with dependent claims directed to the crystalline monohydrate of that salt, XRPD-characterized forms, a pharmaceutical composition, and a method of treating Type 2 diabetes (see Judge Andrews's claim-construction opinion, C.A. No. 19-311-RGA, D.I. 135 (Nov. 17, 2020), and inventor Wenslow's PTAB declaration). The accused technology is Ajanta's proposed generic sitagliptin phosphate tablets (Januvia generic), submitted under ANDA No. 214784 with a Paragraph IV certification against the '708 patent; Merck received notice of that certification "no earlier than May 6, 2020," which triggered this suit filed June 17, 2020. The docket's ANDA cover sheet lists the '708 patent expiry as Nov. 24, 2026 and a 30-month-stay deadline of no earlier than Nov. 6, 2022.

Procedural posture, venue, and significance. The case was assigned to Judge Richard G. Andrews in the District of Delaware (Wilmington) — the district where Merck filed the overwhelming majority of its sitagliptin suits. It was quickly swept into the JPML's coordinated proceeding, In re Sitagliptin Phosphate ('708 & '921) Patent Litigation, MDL No. 19-2902-RGA, with 1:20-cv-00815 appearing on the MDL's associated-case line; the JPML expressly selected Delaware and Judge Andrews to prevent inconsistent claim-construction and validity rulings across what Merck described as 26 ANDAs (JPML transfer order). The docket shows the parties stipulated regarding infringement and the authenticity of documents in late October 2020, with the orders entered Nov. 4, 2020 — i.e., the fight narrows to validity/invalidity-type issues, with claim construction handled MDL-wide on Nov. 17, 2020. The case is notable on several axes: (1) it is part of a coordinated "second-wave" salt/polymorph patent strategy, in which Merck used the later-expiring '708 patent to extend Januvia/Janumet exclusivity past the Jan. 2023 expiry of the earlier compound/first-wave protection, with the franchise generating roughly $5–6 billion in annual sales and over $75 billion cumulative; (2) it is tightly linked to a parallel PTAB wave — IPR2020-00040 (Mylan), plus IPR2020-01045 (Teva/Watson), IPR2020-01060 (Dr. Reddy's), and IPR2020-01072 (Sun) — with Merck reporting that the Board upheld all challenged '708 claims on May 7, 2021 (Merck press release); and (3) it links to the parallel N.D. W. Va. litigation against Viatris/Mylan, where the court in September 2022 found both the '708 and the '921 formulation patents valid and infringed. Ultimately, Merck's sitagliptin actions resolved through a wave of consent judgments/settlements (Dr. Reddy's, Anchen/Par, and others) that permit generic Januvia/Janumet entry in May 2026 (Janumet XR: July 2026), and the MDL was terminated on Feb. 27, 2023, consistent with this case's "settled" status.

Sourcing caveats. The docket, party identities, judge, filing date, ANDA cover-sheet dates, the stipulations, and the MDL consolidation are well documented. Two points are less firmly sourced: I could not retrieve the specific docket entry recording Ajanta's dismissal or consent judgment in 1:20-cv-00815 (the "settled" characterization comes from the case metadata; Merck's own disclosures reference settlements with "ten generic companies" without naming Ajanta in the public excerpt), and Ajanta's FDA tentative-approval dates should be treated as database-reported rather than confirmed from the approval letters themselves. Ajanta also appears as a defendant in a related Delaware action, 1:20-cv-01496 (Merck Sharp & Dohme LLC v. Ajanta Pharma Ltd., filed Nov. 3, 2020, terminated Sept. 14, 2021), which likely concerns the '921 combination patent given Ajanta's sitagliptin/metformin ANDA — but I have not independently verified the patent asserted there.

I'll research this case across multiple sources.

Let me dig deeper into the docket, the IPRs, and the final disposition.

Let me pin down the MDL claim construction order, the certificate of correction, and settlement terms.

Merck Sharp & Dohme Corp. v. Ajanta Pharma Ltd., No. 1:20-cv-00815-RGA (D. Del.)

Bottom line

This was a Hatch‑Waxman § 271(e)(2) case on U.S. Pat. No. 7,326,708 (the sitagliptin dihydrogenphosphate (DHP) salt patent) arising from Ajanta's Paragraph IV ANDA for generic Januvia® (sitagliptin phosphate) tablets. It never reached trial. Ajanta conceded infringement early, the case was litigated as part of MDL No. 2902, In re Sitagliptin Phosphate ('708 & '921) Patent Litigation before Judge Richard G. Andrews, and it terminated by consent judgment on 2021‑09‑15, roughly three weeks before the scheduled 2021‑10‑04 bench trial. There were no contested motions to dismiss, transfer, or stay. The most consequential external event was the PTAB's 2021‑05‑07 Final Written Decision upholding the '708 claims in Mylan v. Merck, IPR2020‑00040 — which Merck promptly put before Judge Andrews (D.I. 58).

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1. Filing and initial pleadings

Note on counterclaims: the docketed title of D.I. 8 is "ANSWER to Complaint and Affirmative Defenses" — i.e., on the face of the public docket, Ajanta pleaded invalidity/non‑infringement defenses but did not file declaratory‑judgment counterclaims. I could not verify this from a full text of D.I. 8 and flag it as a modest uncertainty; the eventual consent judgment dismissed "all claims, counterclaims, affirmative defenses" in the parallel settlements, which suggests counterclaims may have been present in some of the sister cases. Source: Patexia docket compilation for 1:20‑cv‑00815; UniCourt docket summary

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2. Pre-trial motions of substance

There were none of the classic dispositive/venue category in 20‑815. No motion to dismiss, no § 1404 transfer motion, no motion to stay pending IPR, and no motion for summary judgment appears on the docket. Three structural reasons:

1. MDL consolidation did the venue/coordination work. Merck moved under 28 U.S.C. § 1407, and on 2019‑08‑08 the JPML centralized 14 sitagliptin actions (13 already in D. Del., plus the N.D. W. Va. Mylan case) into **MDL No.

I'll research the counsel of record for the plaintiff in this case.

Let me dig into the actual docket and appearances for the plaintiff.

Let me pull the actual docket and complaint filings.

I'll research the docket and counsel for the Ajanta defendants in this D. Del. action.

Let me verify firm affiliations and roles for each defense attorney.

Defense Counsel of Record — Merck Sharp & Dohme Corp. v. Ajanta Pharma Ltd., No. 1:20-cv-00815-RGA (D. Del.)

Bottom line: The Ajanta defendants were represented by a two-tier team typical of ANDA litigation in Delaware — a Wilmington firm as local/Delaware counsel of record, plus a Chicago-based Hatch-Waxman defense group admitted pro hac vice. All six attorneys below appear on the docket as defense counsel. No in-house attorney appeared on the docket in this case.

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1. Delaware counsel of record (file all papers under LR 83.5(d))

Because D. Del. Local Rule 83.5(d) requires Delaware counsel to be the registered CM/ECF users and to file all papers (a point expressly recited in the docket's pro hac vice entry of Aug. 7, 2020), Phillips and Bilson are the operative counsel of record and the proper service contacts.

2. Out-of-state counsel admitted pro hac vice

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Caveats and sourcing notes

• Docket basis: Defense appearances are drawn from the D. Del. docket entries for 1:20-cv-00815 (Answer, D.I. 8; Rule 7.1 disclosures, D.I. 9–10; pro hac vice motions, D.I. 11–12; orders entered Aug. 7, 2020), as reflected on Justia Dockets, UniCourt, and Patexia. The docket reflects no separate in-house counsel appearance.
• Firm name at time of appearance: I confirmed the demographics of the four pro hac vice attorneys as a single Chicago-based Hatch-Waxman defense group that has appeared together for Ajanta, Zydus/Cadila and others, but I could not verify from a primary source (the certifications themselves are not in the public excerpts retrieved) the exact firm name printed on the 2020 pro hac vice certifications. Public professional profiles place Michael J. Gaertner at Locke Lord LLP (Chicago) during this era and at Buchanan Ingersoll & Rooney PC today. Treat the precise 2020 letterhead for Blessing/Cassella/Abramowitz as unverified.
• Relationship to the coordinated litigation: The docket shows this case associated with In re: Sitagliptin Phosphate ('708) Patent Litigation, 1:19-md-02902-RGA before Judge Andrews, so the Ajanta defense team was working within the consolidated sitagliptin MDL.
• Parallel PTAB proceedings: The '708 patent was the subject of IPR petitions (e.g., IPR2020-01060). In that IPR the petitioner was represented by Lerner, David, Littenberg, Krumholz & Mentlik LLP (Russell W. Faegenburg, lead; Tedd W. Van Buskirk; Michael H. Teschner), and Merck/patent owner was represented by Williams & Connolly LLP (Stanley E. Fisher, Bruce R. Genderson, Jessamyn S. Berniker, Alexander S. Zolan, Elise M. Baumgarten, Shaun P. Mahaffy, Anthony H. Sheh). I did not independently confirm that Lerner David's IPR petitioner client was Ajanta, so I would not attribute that IPR representation to the Ajanta defendants without further verification.
• Case status: The case proceeded through fact discovery into late 2020 (per Patexia, filings through D.I. 45, Dec. 17, 2020) and was ultimately settled, consistent with the case metadata. No trial counsel designations or sealed leadership appointments were located in the public record.