Can Cytokinetics stop BMS from asserting its patent against Myqorzo?
Zachary Silbersher
Cytokinetics, Inc. sells a drug, Myqorzo®, indicated for the treatment of obstructive hypertrophic cardiomyopathy (oHCM). The drug’s active ingredient is aficamten, which is a cardiac myosin inhibitor. In 2020, Bristol-Myers Squibb acquired a company that sells one of the only other competing drugs to Myqorzo. Then in May 2026, BMS acquired a patent covering the use of aficamten to treat cardiac hypercontractility. Cytokinetics claims BMS acquired this patent only to stifle Myqorzo’s commercial potential. On August 12, Cyotkinetics filed suit against BMS seeking a judgmentthat it does not infringe BMS’s aficamten patent. Can Cytokinetics extinguish BMS’s patent threat against Myqorzo?
Background of Cytokinetics’ dispute with BMS.
Cytokinetics’ complaint tells a story that has been heard over and over again within the pharmaceutical industry—namely, BMS acquired a patent not as the product of innovation, but as a scheme to stifle competition. The story concerns treatment of HCM, which is a genetic and potentially fatal heart disease characterized by thickening of the heart muscle. Until very recently, treatment for HCM was primarily limited to administration of beta blockers, even though that treatment was never validated through large clinical trials.
Cytokinetics was founded in 1998 with a focus on muscle-related cardiovascular disease. It focused on a pipeline of small molecule drugs that either activate or inhibit cardiac myosin, which is the motor protein responsible for muscle contraction. In 2012, Cytokinetics incubated a new company, MyoKardia, which developed a compound, mavacamten, for the treatment of oHCM. In 2020, BMS acquired MyoKardia and the rights to mavacamten. The drug was eventually approved by the FDA and is currently sold as Camzyos®.
Mavacamten, however, purportedly requires complicated dosing, has long pharmokinetic half-life, and has potential for drug-drug interactions. Cytokinetics therefore spent years developing aficamten, which could also treat oHCM through myosin inhibition, but purportedly without the alleged drawbacks of mavacamten. The FDA approved Cytokinetics’ drug, Myquorzo, in late 2025.
Meanwhile, during aficamten’s development, BMS filed a patent application directed to treating HCM by eliminating or reducing the use of beta blockers and administering a myosin inhibitor. Both Cytokinetic’s drug, aficamten, and BMS/MyoKardia’s drug, mavacamten, are both myosin inhibitors. BMS’s patent, however, was not limited to mavacamten. In fact, it sought to patent treatment of HCM using any myosin inhibitor, which would presumably include Myquorzo’s myosin inhibitor as well.
In 2025, Cytokinetics publicly released clinical trial results for aficamten in advance of its FDA approval. In November of that year, shortly before Myqorzo’s FDA approval, BMS amended its patent application to specifically claim the use of aficamten for the treatment of HCM. Several months later, in April 2026, Cytokinetics asked BMS to confirm whether it intended to assert the patent against Cytokinietics’ drug. BMS purportedly could not provide that assurance. The patent issued in May 2026 as U.S. Patent No. 12,616,297.
Cytokinetic’s Declaratory Judgment lawsuit against BMS.
Cytokinetics’ lawsuit against BMS seeks a declaratory judgment. In other words, Cytokinetics is not alleging that BMS infringes one of Cytokinetics’ lawsuits, but rather, Cytokinetics is asking the Court to find that its drug, Myqorzo, does not infringe BMS’s ’697 patent.
Cytokinetics’ first hurdle is demonstrating that it has standing to seek a declaratory judgment. Courts generally do not issue advisory or hypothetical opinions regarding potential disputes. Rather, a declaratory judgment plaintiff must show that an actual case or controversy exists with the defendant. That typically requires evidence that the defendant (patent holder, in this case BMS) threatened a patent infringement lawsuit against the plaintiff (in this case, Cytokinetics.) In other words, to maintain its declaratory judgment lawsuit against BMS, Cytokinetics is required to show that BMS threatened suit with the ‘697 patent.
Here, that evidence is not as strong as it could be. Cytokinetics points to circumstantial evidence to build a case that it is under imminent threat of suit. It claims that Cytokinetics has exclusive rights to distribute aficamten, and therefore, there is no reason BMS would pursue a patent using aficamten to treat HCM unless it wanted to use the patent to stifle competition with Myqorzo, burden Cytokinetics with expensive patent litigation, and slow Myqorzo’s adoption with by doctors and patients. Cytokinetics also points out that BMS is very litigious, and teeing up a patent that can be used in litigation against Cytokinetics is part of BMS’s purported scheme of “weaponizing the patent system to attack competitors’ branded drug products.” See Cytokinetics, Inc. v. Bristol-Myers Squibb Co., Case No. 1:26-cv-01026 (D. Del.) (ECF 1 ¶ 49).
All of that may indeed be true. But it may also fall short of identifying an imminent threat of being sued by BMS. Cytokinetics’ complaint does not identify any oral or written statement from BMS evidencing an imminent threat of suit alleging the ‘697 patent. Rather, Cytokinetics asked BMS whether it would sue, and BMS apparently did not confirm one way or another. BMS is under no obligation to confirm, one way or another, whether it intends to sue on the ‘697 patent, either now or in the future. Given all this, BMS is likely to file a motion to dismiss on the ground that Cytokinetics lacks standing to bring a declaratory judgment action.
Cytokinetics likely does not infringe the ‘697 patent.
On the other hand, if the case does survive a motion to dismiss, the merits are likely to favor Cytokinetics. The ‘697 patent specifically requires administering aficamten while also discontinuing or reducing beta blocker therapy. Cytokinetics claims that its label for Myqorzo does not include any instructions requiring patients to discontinue or eliminate beta blocker therapy. The devil is in the details, but that is likely the strongest and most obvious defense for Cytokinetics to prove that Myqorzo does not infringe the ‘697 patent.
Cytokinetics is also likely to seek to invalidate the ‘697 patent for lack of written description. Given that Cytokinetics currently owns all patent rights to develop aficamten, BMS lacks any rights to do so. Indeed, the patent contains no data, experiments or studies related to using aficamten to treat HCM. Despite this, the ‘697 patent claims as an invention the use of aficamten to treat patients with HCM symptoms.
Cytokinetics argument will essentially be that BMS’s patent covers a method of using any myosin inhibitor, including aficamten, but its patent lacked sufficient disclosure to describe all embodied species within that genus. In other words, Cytokinetics will argue that BMS attempted to patent more than it actually invented, which is a basis for invalidating a patent. This defense will require expert testimony, but it creates a tractable basis, in addition to non-infringement, for Cytokinetics to evade liability for BMS’ ‘697 patent.
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In sum, the case is in its very early stages. The most likely next step is that BMS will file a motion to dismiss the case on the ground that Cytokinetics lacks standing to maintain a declaratory judgment action. Based on Cytokinetics’ complaint, BMS could very likely prevail on that motion.
In that case, the parties would find themselves in the same place they were before the case was filed. Both have competing, FDA-approved drugs. Meanwhile, BMS owns a patent covering use of drug that it is not technically allowed to distribute or develop. And that patent could create a cloud over Cytokinetics’ drug that has nothing to do with the efficacy or safety of Cytokinetics’ drug.
And then who wins? And is this a scenario that actually harnesses the patent system to improve innovation? Or to do something else?