Atossa Therapeutics Inc. v. Jina Pharmaceuticals Inc.

This case, Atossa Therapeutics Inc. v. Jina Pharmaceuticals Inc., PGR2026-00015, involved a Post-Grant Review (PGR) proceeding before the Patent Trial and Appeal Board (PTAB) of the U.S. Patent and Trademark Office, initiated by Jina Pharmaceuticals Inc. against Atossa Therapeutics Inc. Atossa Therapeutics is a clinical-stage biopharmaceutical company focused on developing novel therapeutics for oncology, particularly breast cancer, with its lead product candidate being (Z)-endoxifen, a potent Selective Estrogen Receptor Modulator/Degrader (SERM/D) also being explored for Duchenne Muscular Dystrophy. Jina Pharmaceuticals Inc. is also an operating pharmaceutical company engaged in the research, development, and commercialization of therapeutic products for cancer and other medical conditions, and has been developing Endoxifen in collaboration with Intas Pharmaceuticals.

The dispute centered on intellectual property related to Endoxifen. While the case metadata and previous sections specify U.S. Patent No. 12,245,997 as the patent at issue, public patent databases do not show an issued patent with this number related to Endoxifen or owned by Atossa Therapeutics. This suggests a potential transcription error in the provided information. However, within the broader settlement that resolved this PGR, Atossa Therapeutics' patents, particularly U.S. Patent Nos. 11,261,151 and 12,071,391, titled "Methods for Making and Using Endoxifen," were explicitly mentioned as being part of the resolved disputes. These patents generally cover methods for preparing and using Endoxifen, a key active metabolite of tamoxifen that is under development for treating various conditions, including estrogen receptor-positive breast cancer. In a PGR, there is no "accused product" in the traditional sense of infringement; instead, Jina Pharmaceuticals, as the Petitioner, challenged the validity of Atossa's patent to potentially clear the path for its own Endoxifen-related products or research.

The procedural posture of this case as a Post-Grant Review before the PTAB is significant because it provides an administrative alternative to district court litigation for challenging patent validity. PGRs allow for a broad range of patentability challenges and typically offer a faster and more cost-effective resolution compared to traditional litigation. This case is notable for several reasons. It involves Endoxifen, a drug with substantial market potential for breast cancer and other indications, representing a multi-billion dollar market. The proceeding was ultimately concluded by a comprehensive settlement agreement that included not only Jina Pharmaceuticals but also Intas Pharmaceuticals Ltd., resolving multiple parallel PTAB challenges concerning Endoxifen-related intellectual property. This broader resolution highlights the strategic importance of Endoxifen in the pharmaceutical industry and the parties' efforts to secure their respective positions in its development and commercialization.

This Post-Grant Review (PGR) proceeding, PGR2026-00015, initiated by Jina Pharmaceuticals Inc. against Atossa Therapeutics Inc., focused on the validity of U.S. Patent No. 12,245,997. The case was ultimately resolved through a comprehensive settlement agreement.

Here are the key legal developments and outcome:

Filing & Initial Pleadings:

• 2025-12-10: Jina Pharmaceuticals Inc. filed the petition for Post-Grant Review (PGR) against Atossa Therapeutics Inc., challenging U.S. Patent No. 12,245,997.

Pre-Institution Proceedings & Related Filings:

• 2025-12-12: Counsel for Petitioner (Intas Pharmaceuticals, with Jina Pharmaceuticals as a real party-in-interest) requested permission from the PTAB to amend its mandatory notices to formally add Jina Pharmaceuticals as a real party-in-interest (RPI) in related proceedings (IPR2025-00799 and PGR2025-00043). Atossa Therapeutics requested a conference call with the Board for guidance on this request and its interrelationship with Atossa's own motion for discovery.
• 2025-12-19: A conference call was held between counsel for Petitioner and Patent Owner and the PTAB judges to discuss adding Jina Pharmaceuticals as an RPI and whether this would moot Atossa's motions for additional discovery related to the RPI dispute.
• 2026-01-05: The PTAB issued an order in related proceedings (IPR2025-00799 and PGR2025-00043), addressing the request to add Jina Pharmaceuticals as an RPI and its impact on discovery motions.
• 2026-01-30: In a separate but related PGR (PGR2023-00043 concerning U.S. Patent No. 11,572,334), the PTAB issued a final written decision finding all challenged claims unpatentable. Atossa Therapeutics chose not to appeal this decision, stating it would pursue new patent applications for its current formulations.

Institution Decision:

• 2026-04-22: The PTAB instituted the Post-Grant Review for PGR2026-00015.

Final Disposition – Settlement:

• 2026-04-13: Atossa Therapeutics Inc. entered into a comprehensive Settlement Agreement with Intas Pharmaceuticals Ltd. and Jina Pharmaceuticals Inc. to resolve all Endoxifen-related patent disputes, including the pending PTAB challenges such as PGR2026-00015.
• 2026-04-16: Atossa Therapeutics publicly announced the settlement.
• 2026-05-11: The PTAB officially recorded the outcome of PGR2026-00015 as "Settlement".
  • The settlement agreement included mutual covenants not to challenge specified Endoxifen-related patents and applications, with limited exceptions. It preserved Atossa's ability to develop and commercialize Z-endoxifen base for oncology, endocrine dysfunction disorders, and muscular dystrophy-related diseases. Atossa expected its two issued U.S. Patents 11,261,151 and 12,071,391, titled "Methods for Making and Using Endoxifen," to remain issued and enforceable against other third parties.

Parallel PTAB IPR/PGR Proceedings:

• This PGR was one of several parallel PTAB challenges concerning Endoxifen-related intellectual property. Jina Pharmaceuticals Inc. was identified as a real party-in-interest in other related PTAB proceedings, specifically IPR2025-00799 and PGR2025-00043, both involving Atossa Therapeutics' patents 11,261,151 and 12,071,391. The comprehensive settlement resolved these multiple challenges.
• The broader landscape of PTAB proceedings in 2025 and 2026 saw evolving policies, including the USPTO Director's increased control over institution decisions and consideration of U.S. manufacturing activity as a discretionary factor, aiming to make the PTAB a more patent owner-friendly forum.

I'll search for counsel of record for Atossa Therapeutics in these PTAB proceedings.

Counsel of record — Plaintiff Atossa Therapeutics, Inc. (Petitioner)

Threshold correction first. The earlier sections of this case file inverted the parties. Per the case metadata (Plaintiff: Atossa) and the PGR2026‑00015 record, Atossa is the Petitioner in PGR2026‑00015, challenging Jina Pharmaceuticals' U.S. Patent No. 12,245,997 (claims directed to a method of treating bipolar I disorder with endoxifen). Jina is the Patent Owner. Two statements in the prior sections should be flagged as contradicted by the search record:

• The "Case overview" statement that Jina initiated the proceeding against Atossa is wrong; the caption's plaintiff (Atossa) filed the petition. Atossa's counsel signs correspondence in this docket expressly as "Counsel for Petitioner Atossa." (PTAB correspondence, Apr. 13, 2026)
• The "Case overview" assertion that no issued patent numbered 12,245,997 exists in public databases is also incorrect; databases index PGR2026‑00015 as Atossa Therapeutics, Inc. v. Jina Pharmaceuticals, Inc. involving Jina's '997 patent. (Arctic Invent case page; IP Verse)

Because this is a PTAB proceeding, there is no PACER docket and no "local counsel" requirement — all appearing counsel must be USPTO-registered practitioners, and appearances are recorded in PTAB E2E/PTAB Center filings rather than a court docket sheet.

Attorneys appearing for Atossa Therapeutics, Inc.

Sourcing detail. Raymond signed the April 13, 2026 request for authorization to file the joint motion to terminate as "Counsel for Petitioner Atossa," with Milea and Baughman copied. Milea signed the February 17, 2026 email requesting that the Board strike Patent Owner's 24-page discretionary-denial request as "Counsel for Petitioner." (Feb. 17, 2026 correspondence) The same Groombridge Wu trio (Raymond, Baughman, Milea) appears on Atossa's side across the parallel Intas challenges — in PGR2025‑00043, third-party analytics list "Respondent Counsel: Raymond, Megan et al." for Atossa. (IP Verse, PGR2025‑00043)

Caveat on lead counsel designation. I could not retrieve the petition's cover-page "Lead Counsel / Backup Counsel" block for PGR2026‑00015 itself; the PTAB Center document links surfaced only the correspondence and the Patent Owner's response. So the firm and the appearing team are well documented, but which of Raymond or Baughman is formally designated Lead Counsel under 37 C.F.R. § 42.8(b)(3) in this specific PGR is not confirmed — in the related Intas matters the petition papers of record list Baughman as lead with Raymond as backup, and that pattern likely repeats here, but I am flagging it as inference rather than record fact. Also note that PTAB petitions typically append a boilerplate reservation for "all practitioners associated with [firm] appearing in any updated mandatory notices," so additional firm attorneys may appear without separate notice.

No in-house counsel identified. Atossa's public filings and the docket correspondence show outside counsel only; I found no Atossa in-house attorney appearing of record. Steven Quay (CEO) is the corporate signatory on Atossa's 8‑Ks, not litigation counsel.

For cross-reference — opposing side (Patent Owner Jina)

Not asked, but corrects the prior "Defendant representatives" section, which treated Jina as the defendant and reported no counsel found. Jina's counsel of record is McAndrews, Held & Malloy — docket correspondence is copied to Alex Menchaca and Ben J. Mahon, with a dedicated service address pgr2026-00015@mcandrews-ip.com. Attorney names were not independently verified against the petition's counsel block, so treat firm affiliation as solid and individual roles as provisional.

Procedural note affecting counsel research

Both sides' appearances exist only in the PTAB's own filing system, and the proceeding was terminated by settlement (joint motion to terminate authorized April 13, 2026; agreement dated April 13, 2026; PTAB recorded "Terminated-Settled"). Settlement-terminated PGRs generate a thin public record, which is why no opinion or press coverage names counsel. There is also an internal date tension in the prior sections worth resolving: they list institution on 2026‑04‑22 but settlement on 2026‑04‑13 and Board authorization of a joint motion to terminate on 2026‑04‑13 — the settlement/termination authorization predates the stated institution date, suggesting either a pre-institution termination or a transposed date in the earlier section.

I'll research this. First, let me establish the party roles and look for docket/filing records.

The docket documents reveal a critical role inversion. Let me dig into the actual PGR filings.

Now let me verify the full counsel lineup and check for additional appearances.

⚠️ Threshold correction: the party roles in the earlier sections are inverted

Before naming counsel, the docket record from PTACTS requires a correction to the previously generated sections — and it changes who the "defendant" is.

The actual caption of PGR2026-00015 is Atossa Therapeutics, Inc. (Petitioner) v. Jina Pharmaceuticals, Inc. (Patent Owner), concerning Jina's U.S. Patent No. 12,245,997, "Endoxifen for the treatment of bipolar I disorder" (issued March 11, 2025; App. No. 17/226,671; priority April 10, 2020; assignee Jina Pharmaceuticals, Inc., Libertyville, IL).

• The Board's own email of April 13, 2026 states: "Petitioner Atossa and Patent Owner Jina have entered into a settlement agreement resolving their dispute in the above-captioned matter," signed "Megan Raymond, Counsel for Petitioner Atossa." (PTACTS artifact)
• Jina's Patent Owner Preliminary Response refers to "Atossa Therapeutics, Inc. ('Petitioner')" petitioning for review of claims 1–10. (PTACTS artifact)

Consequences for the earlier sections (flagging explicitly, per instructions):

1. Prior sections wrongly describe Jina as the petitioner and Atossa as patent owner. It is the reverse.
2. The '997 patent is Jina's, not Atossa's — so the earlier statement that public databases "do not show an issued patent with this number" is incorrect; US 12,245,997 B2 issued March 11, 2025 to Jina.
3. The "Institution Decision — 2026-04-22" entry is inconsistent with the record: the case was terminated by joint motion prior to institution following the April 13, 2026 settlement (Arctic Invent case note). Institution could not have issued a week after termination.
4. The PGR2023-00043 final written decision date is January 29, 2025 (Paper 37), not January 30, 2026, per the Intas petition's own citation.
5. Atossa's "plaintiff" counsel are identifiable (contrary to the prior "Plaintiff representatives" section) — see the cross-reference table below.

Counsel of record for the defendant(s) — Jina Pharmaceuticals, Inc. (Patent Owner)

Jina's appearances come from its Patent Owner's Power of Attorney filed in PGR2026-00015, which appoints two named practitioners plus every practitioner associated with PTO Customer Number 23446 (McAndrews, Held & Malloy, Ltd.):

Source: Patent Owner's Power of Attorney, PGR2026-00015 (service copy certifying service on Petitioner's counsel; the certificate's date reads "December 31, 2026," which is almost certainly an OCR/typo for 2025 given the December 2025 filing of the petition).

Points to note on the Jina side:

• No local counsel, and none required — the PTAB does not use local-counsel rules; McAndrews (Chicago) appears pro hac vice-free under its registration numbers.
• No in-house counsel for Jina appears on the public record. I found no Jina-employed attorney listed in any Board filing; Jina's named inventors (Ateeq Ahmad, Imran Ahmad, Moghisuddin Ahmad, Shoukath M. Ali, Saifuddin Sheikh) are not registered practitioners of record.
• Conflict/overlap flag: the same firm and the same two attorneys represent Intas Pharmaceuticals Ltd. against Atossa in IPR2025-00799 and PGR2025-00043, while representing Jina here. That overlap is what drove Atossa's RPI/discovery motions described in the earlier sections, and Atossa argued Intas was "the sole party funding this PGR" while Jina had "its own interest in the outcomes." This is well documented in Intas's responsive filing (PTACTS artifact).
• Unconfirmed additional practitioner: Amanda C. Jackson (Reg. 77,549, McAndrews) was named backup counsel on the Intas-side petitions and would fall within Customer No. 23446, but I could not confirm she made an appearance in PGR2026-00015 specifically. Treat as unverified.
• Docket anomaly worth noting: an exhibit-support declaration filed by McAndrews paralegal Sayem Osman in PGR2026-00015 carries the caption "INTAS PHARMACEUTICALS LTD., Petitioner v. JINA PHARMACEUTICALS, INC., Patent Owner" (PTACTS artifact). That appears to be template carry-over from the firm's Intas filings; the operative caption throughout the Board's own correspondence is Atossa v. Jina.
• Sealing: the settlement agreement and joint motion papers were kept confidential under 35 U.S.C. § 327, but counsel appearances themselves are not sealed — the POA and service list are public.

Cross-reference: Petitioner/plaintiff side (correcting the earlier gap)

Since the prior "Plaintiff representatives" section reported that no names could be found, here is the record evidence — useful for completeness rather than as the answer to this task:

Service address for Petitioner: Atossa-Intas@groombridgewu.com.

Sourcing caveats

The attorney identities, registration numbers, firm addresses, and roles above are drawn directly from PTAB filings and Board emails in the PTACTS record for PGR2026-00015 and are reliable. The experience notes are grounded in docket documents I retrieved (the Intas petitions and cited FWD), but I was cut off before completing bio verification on McAndrews' and Groombridge's firm websites, so I have deliberately not supplied Bar-admission dates, law-school details, or case lists beyond what the PTAB papers themselves show. Nothing here should be treated as confirming current firm titles (e.g., "shareholder") or office relocations.