1.) Recent ANDA approvals 2.) Astellas v. Ascent -Mirabegron. What is happening with the mirabegron market in the US?
Contents
Recent ANDA approvals
General information
Thousands in UK sue Johnson & Johnson over talcum powder cancer risks
HC refuses to bar AET Lab on drug for chemotherapy-induced nausea, vomiting
Intellectual Property
Astellas v. Ascent -Mirabegron
Recent ANDA approvals
We follow ANDA approvals. In September, the USFDA issued a total of 57 ANDA approvals, of which 13 were tentative. A tentative approval is a formal notification from the USFDA indicating that a generic drug application has met all scientific and regulatory requirements for safety, efficacy, and quality, but cannot be granted final marketing approval due to unexpired patents or market exclusivities held by the original brand-name drug. The companies that could seek more than two ANDA approvals (including tentative ones) in September were as follows.
Some of our other comments about a few ANDA approvals sought by Indian companies are listed below.
General information
Thousands in UK sue Johnson & Johnson over talcum powder cancer risks
A major legal claim has been filed in the UK against pharmaceutical giant Johnson & Johnson, accusing the firm of knowingly selling baby powder contaminated with asbestos. The claim involves 3,000 people and focuses on internal memos and scientific reports, which have been seen by the BBC. News hereHC refuses to bar AET Lab on drug for chemotherapy-induced nausea, vomiting
Rejecting an interim injunction plea by Helsinn Healthcare SA, the Delhi High Court has refused to restrain a German company Alfred E. Tiefenbacher GmbH & Co. KG. and its wholly owned Indian subsidiary AET Laboratories Pvt. Ltd. from manufacturing, selling drugs for treatment of chemotherapy-induced nausea and vomiting. The petitioner, a Swiss pharmaceutical company, manufactures and markets an oral dosage form comprising Palonosetron and Netupitant, which is protected under the claims of the patent, under the mark 'AKYNZEO'. News hereIntellectual Property
Astellas v. Ascent -Mirabegron
This write-up discusses the recommendation from the United States District Court for the District of Delaware concerning the motion by Astellas Pharma Inc. and its affiliates ("Plaintiffs" or "Astellas") to dismiss counterclaims of inequitable conduct and strike related affirmative defences filed by Ascent Pharmaceuticals, Inc. ("Defendant" or "Ascent"). The Court recommends that Astellas's motion be GRANTED-IN-PART and DENIED-IN-PART. The core dispute is a patent infringement case related to Astellas's overactive bladder drug, Myrbetriq (containing mirabegron as the active ingredient), which is covered by New Drug Application (NDA) No. 202611. The patents in suit (the "Asserted Patents") are U.S. Patent Nos. 10,842,780 ('780 Patent), 12,059,409 ('409 Patent), 11,707,451 ('451 Patent), and 12,097,189 ('189 Patent). Ascent, a generic manufacturer, is seeking to market a generic version of Myrbetriq. The OB listed patents are as follows.
- Ascent alleged that Astellas committed inequitable conduct by failing to disclose to the Patent Office that certain prior art—specifically U.S. Patent No. 6,699,503 ('503 Patent) and its equivalents, US 6,436,441 ('441 Patent)—was listed in the Orange Book as covering Myrbetriq. Ascent argued that this constituted an inconsistent position between the FDA (by listing the patent) and the Patent Office (by arguing the prior art did not teach the claimed mirabegron release profile or was irrelevant).
- Court's Finding: The Court found no plausible allegation of but-for materiality. The prior art references ('503 and '441 Patents) were provided to and expressly considered by the examiner, who rejected claims over them. The Court stated that simply arguing inconsistently before different agencies does not, on its own, establish but-for materiality; Ascent failed to plead that Astellas made a false statement or that the Patent Office would have rejected the claims had it known of the Orange Book listing.
- Recommendation by The Court: The counterclaims based on the Orange Book listing should be dismissed.
2. Withheld Litigation Documents
- Ascent alleged that Astellas improperly withheld broad categories of "material information from litigation" relating to the '780 Patent and other patents, including "pleadings, briefs, court rulings, expert reports, contentions, trial testimony and deposition testimony".
- Court's Finding: Ascent's pleading lacked the particularity required by Rule 9(b). Ascent failed to identify which specific documents, which claims, or what information in those documents was material to the '409, '451, and '189 Patents. The only specific document identified, Judge Bataillon's June 9, 2023 order invalidating the '780 Patent ("the '780 Order"), was disclosed to the Patent Office. Therefore, but-for materiality for the '780 Order was lacking.
- Recommendation by the Court: The counterclaims based on withheld litigation documents should be dismissed.
3. Dihydrochloride Salt in Examples
- Ascent alleged that Astellas failed to disclose during prosecution of the '451 and '189 Patents that the examples therein were carried out with a dihydrochloride salt, not mirabegron.
- Court's Finding: This claim was found to be legally deficient. The allegedly "omitted" material (the examples) was set forth in the patent applications themselves and was before the examiner. Ascent did not allege that Astellas falsely stated the examples used mirabegron, only that they omitted the fact that a dihydrochloride salt was used. As an alleged omission regarding material before the examiner, Ascent failed to plead but-for materiality, i.e., how failing to explain an example in the application under review resulted in a claim being allowed when it should not have been.
- Recommendation by the Court: The counterclaims based on the dihydrochloride salt in examples should be dismissed.
The Report and Recommendation were filed on September 22, 2025. Decision here In short, the court mostly sided with Astellas, recommending that the judge dismiss almost all of Ascent's counterclaims. These claims argued that Astellas committed inequitable conduct by hiding information from the Patent Office during the application process. The court ruled that Ascent failed to provide enough specific facts to support these serious accusations, calling many of them legally insufficient. The only part of Ascent's defence that survived was one of its estoppel arguments, meaning that the core issue of patent infringement will proceed to trial. Ultimately, this decision removes Ascent’s strongest argument for invalidating Astellas’s patents entirely. Next Action and The parties now have fourteen days to file any objections to this Report and Recommendation with the District Judge. The judge will then review the recommendation and make the final ruling on which claims and defences are allowed before the trial, which is scheduled to begin on October 27, 2025. What is happening with the mirabegron market in the US?
In the meantime, there were generic launches in the US markets. The launch of generic mirabegron extended-release (ER) tablets in both 25 mg and 50 mg strengths began in the U.S. market around the second quarter of 2024. Comparative indicative prices in the US market are as follows.
