Can Ascendis avoid an ITC ban of its TransCon CNP based on public interest grounds?
Zachary Silbersher
Biomarin’s campaign to block Ascendis from importing its new TransCon CNP drug is getting into the thick of it. The Markman hearing is scheduled for February, and the evidentiary hearing is scheduled for late April. In a prior post, I discussed the upcoming Markman hearing, which both parties are likely to rely upon to tee up arguments on infringement and invalidity. Yet, even if Ascendis fails to prove that it does not infringe the patent, and also fails to invalidate the patent, there are two additional defenses that Ascendis could rely upon—public interest and intervening rights. What are these defenses, and how strong are they?
This post will address public interest, and intervening rights will be addressed in another post.
Biomarin has filed an action in the International Trade Commission (ITC) against Ascendis. If Biomarin is successful, the ITC will bar Ascendis from importing ingredients required to market and sell its TransCon CNP drug. Yet, to be successful, Biomarin must do more than simply prove that Ascendis is infringing its ‘267 patent. For the ITC to issue an importation ban, the Commission must also determine that such a ban is within the public interest.
Here, Ascendis has already articulated a public interest argument that has meaningful traction. Biomarin’s Voxzogo® drug is indicated for pediatric treatment of achondroplasia. Biomarin’s drug requires daily administration, which means that children are required to have a daily injection. By contrast, Ascendis’ TransCon CNP is a delayed release formulation that only requires weekly injections.
Given this, Ascendis has argued that an importation ban would be contrary to the public interest. Even if we assume that Ascendis’ drug is equally efficacious to Biomarin’s drug, Ascendis’ drug allows children to receive weekly injections. If its drug is banned, that will essentially compel children to take daily injections even though weekly ones are available. Ascendis has argued that, “[d]ramatically reducing the injections that a young child must endure is a significant benefit physically (reducing patient noncompliance issues) and psychologically (reducing distress).” (See ITC Inv. No. 337-1447, April 16, 2025 at 2). On its face, that is a fairly compelling public interest basis to forego instituting a ban on Ascendis’ drug.
Is there precedent for this? Part of the difficulty handicapping Biomarin’s case against Ascendis is that it has historically been rare for pharmaceutical companies to use the ITC to block competitors. The reason is because, to bring an ITC action, the complainant, which in this case is Biomarin, must satisfy what is known as the “domestic industry” requirement. That essentially requires the complainant demonstrate that it doing enough within the U.S., usually manufacturing, with respect to the claimed patent.
For pharmaceutical companies, satisfying the domestic industry requirement has been historically difficult. Many pharmaceutical companies manufacture and engineer their drugs abroad. Their U.S. activities have been limited to marketing and sales. Under prior legal precedent, manufacturing within the U.S. was essentially required, and marketing and sales activities didn’t count towards satisfying the domestic industry requirement. That essentially barred pharmaceutical companies from using the ITC as a mechanism to block competitors.
All that changed in March 2025. The Federal Circuit, which is the authoritative appellate court on patent issues, issued a precedential decision that effectively changed the law. The case was Lashify, Inc. v. ITC, Case No. 2023-1245 (Fed. Cir. Mar. 5, 2025). The Court broadened the scope of U.S. activities that can satisfy the domestic industry requirement, and permitted activities such as warehousing, quality control and distribution to count. That essentially opened a door to ITC patent enforcement for pharmaceutical companies against competitors that did not previously exist.
The Lashify decision has the potential to usher in a new era of patent disputes between pharmaceutical competitors. Biomarin’s case against Ascendis is a case in point. The Lashify decision issued in early March 2025, Ascendis filed its NDA with the FDA on March 31, 2025, and Biomarin commenced the ITC action the next day.
Nevertheless, given that Biomarin’s case is a fairly unique instance of pharmaceutical patent enforcement at the ITC, there is not tremendous precedent for how the ITC weighs the public interest requirement for healthcare related drugs. There is some precedent in district courts where judges have been disinclined to issue injunctions that would bar the best available healthcare to patients based upon a finding of patent infringement. It is one thing for a court to deprive consumers of the latest versions of certain electronic devices, but it is quite another for a court to issue an order knowing patients will lose access to the best possible healthcare.
In the context of pharmaceutical drugs, sometimes defendants in patent cases have argued against injunctions on the ground that a small portion of the patient population is either immune or allergic to the plaintiff’s drug, and those patients will therefore have to go without treatment if the defendant’s drug is enjoined. By contrast, Ascendis can argue that an importation ban will essentially affect the entire patient population. Every child will have to continue with daily injections even though weekly injections are available.
The public interest requirement may prove instrumental in Ascendis’ defense against Biomarin. The limited Markmanbriefing that is publicly available shows that, in many instances, Ascendis may be grabbing at straws to tee up a non-infringement defense. Ascendis is attempting to narrow the scope of the ‘267 patent, presumably to make it easier to show that its TransCon CNP drug falls outside the patent. That’s typically an uphill battle unless there is a compelling basis to do so. It is also telling that the Staff Attorney’s claim construction positions are generally closer to those of Biomarin than those of Ascendis.
Given this, if Ascendis can’t prove infringement, it may be forced to rely upon its public interest argument to avoid an importation ban. Here, its argument has legs—it has intuitive appeal, it’s not a weedy technical argument, and Biomarin may have trouble countering given that Biomarin is also pursuing a delayed release formulation.