Details for Patent: 12,005,042

Which drugs does patent 12,005,042 protect, and when does it expire?

Patent 12,005,042 protects BARHEMSYS and is included in one NDA.

This patent has twenty-two patent family members in fourteen countries.

Summary for Patent: 12,005,042

Title:	Rescue treatment of post operative nausea and vomiting
Abstract:	Amisulpride is useful in the treatment of postoperative nausea and/or vomiting in a patient, wherein the patient has already been administered a prophylaxis drug for postoperative nausea and/or vomiting, and wherein the dose of amisulpride is 7.5 to 15 mg.
Inventor(s):	Julian Clive Gilbert, Robert William Gristwood, Gabriel Fox
Assignee:	Acacia Pharma Ltd
Application Number:	US17/746,032
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 12,005,042
Patent Claim Types: see list of patent claims	Use;

United States Patent 12,005,042: Amisulpride PONV Claims, Scope, Expiration Risk, and Patent Landscape

U.S. Patent No. 12,005,042 protects a narrow clinical-use protocol for intravenous racemic amisulpride in postoperative nausea and vomiting. The core combination is a 9.5-10.5 mg dose, prior administration of a non-amisulpride prophylaxis drug, and IV infusion over approximately 20 seconds to 20 minutes. The strongest commercial relevance is to BARHEMSYS, the FDA-approved intravenous amisulpride product for PONV.

The patent does not broadly protect amisulpride, all antiemetic uses, or every IV amisulpride regimen. Its enforceability depends on proving each limitation, including the prior prophylaxis, dose range, infusion duration, and PONV indication.

What does U.S. Patent 12,005,042 protect?

The independent claims protect two related methods:

Claim	Protected subject matter
Claim 1	Treating PONV with amisulpride at 9.5-10.5 mg after prior administration of a non-amisulpride prophylaxis drug, using IV infusion over approximately 20 seconds to 20 minutes
Claim 17	Treating PONV with racemic amisulpride at 10 mg after prior non-amisulpride prophylaxis, using IV infusion over approximately 20 seconds to 20 minutes

Claim 17 is narrower in chemical form and dose because it requires racemic amisulpride and exactly 10 mg. Claim 1 is broader on those points because it covers amisulpride generally within the 9.5-10.5 mg range, although dependent claim 7 separately specifies the racemate.

The claim structure is cumulative. A competing product or treatment protocol must satisfy every limitation of the asserted claim to create a direct literal infringement case.

How should the independent claims be construed?

Claim 1 limitation analysis

Limitation	Scope and commercial meaning
“Method for treating PONV”	The administration must be directed to postoperative nausea, postoperative vomiting, or both
“Administering amisulpride”	The active ingredient must be amisulpride; another D2 antagonist alone does not satisfy this limitation
“9.5 mg to 10.5 mg”	The range covers the claimed endpoints and ordinary doses within the range, including 10 mg
“Patient has been administered a non-amisulpride prophylaxis drug prior to surgery”	The patient must receive a prophylactic drug before surgery, and that drug cannot be amisulpride
“IV infusion”	The drug must be delivered intravenously by infusion rather than oral, intramuscular, or other administration
“About 20 seconds up to about 20 minutes”	The infusion must fall within the claimed approximate period, subject to construction of “about”

The prior prophylaxis limitation is commercially significant. It narrows the patent to rescue or treatment use after a patient has already received another prophylactic drug. A 10 mg IV amisulpride treatment administered to a patient who received no preoperative antiemetic would not meet this limitation as written.

Claim 17 limitation analysis

Claim 17 requires:

1. PONV treatment;
2. racemic amisulpride;
3. a 10 mg dose;
4. prior non-amisulpride prophylaxis; and
5. IV infusion over approximately 20 seconds to 20 minutes.

This claim is likely the most directly aligned with a standard 10 mg BARHEMSYS administration protocol, but it is also more vulnerable to design-around strategies involving a non-racemic form, a dose outside 10 mg, or a delivery mode that is not characterized as an infusion.

What dependent claims add to the patent’s scope?

The dependent claims create narrower fallback positions around prophylaxis, combination therapy, timing, infusion duration, dose, and dosing frequency.

Claim group	Added limitation
Claim 2	Prior prophylaxis is not a D2 antagonist
Claim 3	Prior prophylaxis is a 5-HT3 antagonist, corticosteroid, H1 antihistamine, anticholinergic, H2 antagonist, or NK1 antagonist
Claims 4-6	Amisulpride is used sequentially or simultaneously with another antiemetic
Claim 6	The additional antiemetic may be dexamethasone, ondansetron, granisetron, palonosetron, aprepitant, netupitant, or rolapitant
Claim 7	Amisulpride is substantially racemic
Claims 8-10	Administration occurs within one hour, 30 minutes, or 15 minutes after the first emetic or nausea episode
Claims 11-14	More limited infusion periods of approximately 1-15, 1-10, 1-5, or 1-2 minutes
Claim 15	Dose is 10 mg
Claim 16	Single daily dose

Claims 2 and 3 provide useful prosecution and litigation positions because they identify conventional prophylaxis regimens. Claims 8-10 focus on rescue treatment soon after symptoms begin. Claims 11-14 are particularly relevant to hospital protocols that administer IV amisulpride over one to two minutes.

What formulations are protected by U.S. Patent 12,005,042?

The patent claims a method of administration, not a broad composition or formulation.

The claims cover use of an amisulpride formulation when the formulation is:

• administered intravenously;
• delivered by infusion;
• administered at the specified dose;
• used for PONV treatment; and
• given after a non-amisulpride prophylaxis drug.

The patent does not, based on the supplied claims, expressly require a particular:

• concentration;
• vial size;
• excipient;
• pH;
• preservative;
• buffer;
• container;
• stability profile; or
• manufacturing process.

A competing manufacturer could therefore avoid these claims only if its clinical administration falls outside the claimed method. Changing the vial, excipient, concentration, or packaging alone would not necessarily avoid infringement if the same patented administration protocol is practiced.

When does U.S. Patent 12,005,042 lose exclusivity?

The patent issued on June 11, 2024. The statutory expiration date cannot be established from the claims alone because it depends on the earliest effective nonprovisional priority date, any patent-term adjustment, patent-term extension, terminal disclaimer, and applicable regulatory extensions.[1][5]

The patent’s practical exclusivity period should be analyzed through four dates:

Date	Relevance
Earliest effective priority date	Establishes the baseline 20-year patent term
Patent issue date	Determines when the issued claims became enforceable, subject to statutory limits
Patent-term adjustment	Can extend the term for qualifying USPTO delays
Patent-term extension	May apply to qualifying regulatory review periods, subject to statutory limits

For commercial planning, the relevant date is the later of the patent’s enforceable term and the remaining valid Orange Book-listed patent protection for BARHEMSYS. A generic applicant can challenge the patent before expiration through an ANDA Paragraph IV certification.

What is the Orange Book status of the patent?

The FDA Orange Book is the controlling public source for identifying patents submitted by an NDA holder for an approved drug.[3] An Orange Book listing does not itself prove that every claim is valid or infringed. It informs the ANDA certification process and can trigger the Hatch-Waxman litigation stay.

The relevant product is BARHEMSYS injection, containing amisulpride, marketed for:

• prevention of PONV in adults; and
• treatment of PONV in adults who have received antiemetic prophylaxis and still have symptoms.[2]

The patent claims closely track the second use category. That alignment increases the likelihood that an ANDA applicant seeking an indication covering rescue treatment after prophylaxis would confront this patent or a related patent family.

The principal regulatory distinction is between:

1. a full-label ANDA seeking the same PONV treatment indication; and
2. a section viii carve-out removing the patented method from the proposed labeling.

A section viii strategy is difficult where the remaining label, prescribing information, or customary use would still encourage the patented treatment protocol. The risk depends on the exact Orange Book listing, the proposed label, and the wording of any use code.

What Paragraph IV challenges could target this patent?

An ANDA applicant could challenge the patent through a Paragraph IV certification on several grounds:

Noninfringement

The applicant could argue that its proposed labeling or use does not require:

• prior non-amisulpride prophylaxis;
• a 9.5-10.5 mg dose;
• IV infusion;
• infusion within the claimed duration; or
• treatment of postoperative nausea or vomiting.

The strongest design-around position would avoid the full combination rather than modify a peripheral formulation feature.

Invalidity for anticipation

An anticipation challenge would require a single prior-art reference to disclose every limitation of an asserted claim arranged as claimed. The critical combination is not merely IV amisulpride for PONV. The reference would need to disclose the specified dose, prior prophylaxis, and infusion period.

Invalidity for obviousness

An obviousness challenge could combine prior art addressing:

• amisulpride as a D2/D3 antagonist;
• IV amisulpride for nausea or vomiting;
• rescue treatment after failed prophylaxis;
• 10 mg dosing; and
• short IV infusion periods.

The patent holder would likely rely on clinical data, dosing tolerability, efficacy after prophylaxis, and the claimed treatment sequence to rebut an obviousness case. The evidentiary strength would depend on whether the prior art suggested the specific combination rather than merely each element separately.[1][4]

Written description and enablement

The claims cover multiple prophylaxis classes, co-administered antiemetics, infusion durations, and symptom-timing windows. A challenger could examine whether the specification supports the full breadth of those combinations and whether the disclosure enables the claimed scope without undue experimentation.

What patent litigation affects amisulpride and BARHEMSYS?

The relevant litigation risk is likely to arise when an ANDA applicant seeks FDA approval for a generic IV amisulpride product. A Paragraph IV notice can lead to a patent infringement action under 35 U.S.C. §271(e)(2), which can impose a 30-month stay of approval if the NDA holder or patent owner files suit within the statutory period.[5]

Potential defendants would include:

• the ANDA applicant;
• the generic manufacturer;
• an authorized generic sponsor, if applicable; and
• entities involved in commercial distribution under an infringing label.

The principal litigation issues would be claim construction of “about,” the meaning of “IV infusion,” the required sequence of prophylaxis and treatment, and whether the proposed ANDA label induces the patented method.

No biosimilar pathway applies. Amisulpride is a small-molecule drug, so competitive entry would proceed through an ANDA rather than a biosimilar application under the Public Health Service Act.

How strong is the patent estate for amisulpride PONV treatment?

U.S. Patent 12,005,042 is strongest against a generic that copies the labeled BARHEMSYS rescue-use protocol:

• 10 mg IV amisulpride;
• postoperative nausea or vomiting;
• prior prophylactic antiemetic;
• infusion over a short hospital-administered period.

Its strength is lower against products or protocols that:

• use oral amisulpride;
• use a non-IV route;
• treat non-postoperative nausea;
• use a dose below 9.5 mg or above 10.5 mg;
• omit prior prophylaxis;
• use amisulpride only as preoperative prophylaxis;
• use a different active compound; or
• administer outside the claimed infusion duration.

The patent’s scope is therefore commercially meaningful but narrow. It does not create a platform monopoly over amisulpride or all PONV treatment.

How does this patent compare with formulation and manufacturing patents?

A method-of-use patent protects clinical conduct. Formulation and manufacturing patents protect different activities.

Patent category	Typical protected subject matter	Relevance to generic entry
Method-of-use	Dose, indication, treatment sequence, patient population	Can block labeled use or create induced-infringement risk
Formulation	Concentration, excipients, stability, injectable composition	Can block copying of the marketed product formulation
Manufacturing	Synthesis, purification, crystallization, sterile processing	Can require an alternative process or supplier
Device or container	Vial, delivery system, injector, packaging	Usually narrower than the drug-use patent
Regulatory exclusivity	FDA statutory exclusivity	Independent of patent validity and expiration

A generic may avoid the claims of Patent 12,005,042 while still facing separate formulation or process patents. Conversely, invalidation of this method patent would not automatically remove other Orange Book-listed patents.

What generic launch scenarios exist?

Scenario	Likely outcome
Full-label ANDA copies 10 mg IV rescue treatment after prophylaxis	High patent challenge and litigation risk
ANDA uses a section viii carve-out for the patented rescue indication	Regulatory and induced-infringement risk depends on the remaining label
Product uses a different dose outside 9.5-10.5 mg	Reduced literal infringement risk, but potential doctrine-of-equivalents arguments remain
Product uses oral or non-IV amisulpride	Outside the supplied claims
Product targets non-PONV nausea or vomiting	Outside the supplied claims unless the use overlaps PONV
Product uses IV amisulpride without prior prophylaxis	Outside the core prior-prophylaxis limitation
Product launches after patent expiry	Patent-based entry risk declines, subject to other listed patents

The most commercially realistic pathway is a Paragraph IV challenge combined with a proposed label that narrows or removes the patented rescue-treatment use. The outcome would depend on the patent family, Orange Book listings, use codes, and settlement terms.

What licensing and commercial rights matter?

BARHEMSYS was developed by Acacia Pharma and is now associated with Cosmo Pharmaceuticals following Cosmo’s acquisition of Acacia. Commercial rights, supply arrangements, and patent enforcement authority may be divided among the NDA holder, patent owner, affiliates, and commercialization partners.

A complete licensing analysis requires review of:

• patent assignments;
• exclusive license agreements;
• FDA application ownership;
• commercialization agreements;
• supply agreements; and
• any ANDA settlement or authorized-generic arrangement.

The patent itself does not establish the terms of those commercial agreements. Any settlement with a generic applicant would need separate review for entry date, acceleration clauses, authorized-generic rights, and patent challenge restrictions.

Key Takeaways

• U.S. Patent 12,005,042 is a narrow method-of-use patent for IV amisulpride treatment of PONV.
• The central claim combination is 9.5-10.5 mg amisulpride, prior non-amisulpride prophylaxis, and IV infusion over approximately 20 seconds to 20 minutes.
• Claim 17 focuses on racemic amisulpride at exactly 10 mg and is closely aligned with the BARHEMSYS rescue-treatment protocol.
• The patent does not broadly cover oral amisulpride, all antiemetic uses, all doses, or all formulations.
• Generic applicants would likely face Paragraph IV, section viii, or inducement issues if seeking approval for the same rescue-treatment indication.
• Biosimilar litigation is not relevant because amisulpride is a small molecule.
• Patent expiration cannot be calculated from the claims alone and must be confirmed against the patent’s priority chain, patent-term adjustment, terminal disclaimers, and any regulatory extension.
• Separate formulation, manufacturing, or related method-of-use patents may materially affect launch timing.

FAQs

Can a generic use a different amisulpride dose to avoid Patent 12,005,042?

Potentially. A dose outside the 9.5-10.5 mg range would not literally satisfy claim 1, but other patents, label-based inducement theories, or the doctrine of equivalents could remain relevant.

Does the patent cover amisulpride administered before surgery?

The supplied claims require treatment of PONV and prior administration of a non-amisulpride prophylaxis drug. They do not expressly claim amisulpride used solely as preoperative prophylaxis.

Is a 10 mg IV bolus the same as an IV infusion under the patent?

Not necessarily. Claim construction would determine whether a particular administration is an “IV infusion.” A rapid administration may create a noninfringement argument, but the result would depend on the clinical protocol and evidence.

Can a generic omit the patented indication from its FDA label?

A section viii carve-out may be available in some circumstances. The carve-out must remove the patented method without leaving labeling that encourages the infringing use.

Does invalidation of Patent 12,005,042 eliminate all BARHEMSYS exclusivity?

No. Other patents, regulatory exclusivity, formulation rights, manufacturing patents, or related method-of-use claims could continue to affect market entry.

References

1. United States Patent and Trademark Office. (2024). U.S. Patent No. 12,005,042.
2. U.S. Food and Drug Administration. (2020). BARHEMSYS (amisulpride) injection prescribing information.
3. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, commonly known as the Orange Book.
4. U.S. Food and Drug Administration. (2019). Small business assistance: Frequently asked questions on the patent certification process.
5. 35 U.S.C. §§ 156, 271(e), 282, 284, 285.

Drugs Protected by US Patent 12,005,042

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Lxo Ireland	BARHEMSYS	amisulpride	SOLUTION;INTRAVENOUS	209510-001	Feb 26, 2020		RX	Yes	Yes						PREVENTION OF POST-OPERATIVE NAUSEA AND VOMITING
Lxo Ireland	BARHEMSYS	amisulpride	SOLUTION;INTRAVENOUS	209510-001	Feb 26, 2020		RX	Yes	Yes						PREVENTION AND TREATMENT OF POST-OPERATIVE NAUSEA AND VOMITING
Lxo Ireland	BARHEMSYS	amisulpride	SOLUTION;INTRAVENOUS	209510-001	Feb 26, 2020		RX	Yes	Yes						TREATMENT OF POST-OPERATIVE NAUSEA AND VOMITING
Lxo Ireland	BARHEMSYS	amisulpride	SOLUTION;INTRAVENOUS	209510-002	Sep 1, 2020		RX	Yes	Yes						PREVENTION AND TREATMENT OF POST-OPERATIVE NAUSEA AND VOMITING

International Family Members for US Patent 12,005,042

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2018218310
Australia	2024203155
Brazil	112019016565
Canada	3052535