Transparency So Radical It Overlooks Law and Tradition: FDA Releases Complete Response Letters for Unapproved Drugs

On September 4, 2025, the U.S. Food and Drug Administration (FDA) made good on a threat it had been making for months, effectuating the prompt release of complete response letters (CRLs) in “real time” regardless of the approval status of the products to which the CRLs pertain.¹ Alongside the announcement, FDA released a batch of 89 previously unpublished CRLs, which generally related to pending or withdrawn applications.

FDA’s new CRL release policy breaks from the agency’s longstanding practice of treating CRLs as confidential, as the agency treats all parts of applications that have not yet been approved. Indeed, the new policy and the release of the 89 letters appear to contravene FDA’s own regulations, which require confidentiality of the highly sensitive, trade secret, and commercially confidential information pervasive throughout pending applications, including in complete response letters.

Drug sponsors must now assume that information submitted in their engagement with FDA may end up in the public domain through a complete response letter, notwithstanding the regulations and the accompanying assurances of confidentiality under which that sensitive information was submitted to the agency. As we discussed in an earlier Advisory, this change will have significant implications in many areas, and it may only be a matter of time before the new policy is challenged in court.

FDA’s New CRL Release Policy

When FDA determines that a drug application is not approvable, it sends a complete response letter to the drug’s sponsor to explain the agency’s reasoning and identify deficiencies with the application.² But those letters have never been made public before the drug is approved; rather, disclosure has been precluded by FDA’s regulations, which prevent the agency from disclosing the existence of unapproved applications, and also from disclosing any of the data and information contained in an unapproved application.³

FDA began chipping away at those protections in July 2025 when FDA Commissioner Makary published an op-ed in the Washington Post declaring that FDA planned to begin publishing CRLs “in real time” for unapproved drugs.⁴ Commissioner Makary touted the new policy as “good for business and, most important, good for patients.” The agency publicly released about 200 CRLs at that time as well, though those were letters relating to approved drugs, and as such, most had already been made public.

The FDA has now formalized the policy that the commissioner previewed in his op-ed. Going forward, the agency is promising to release CRLs in real-time (i.e., shortly after issuing them to sponsors), as well as to publish previous CRLs for applications that were subsequently withdrawn or abandoned.⁵

Commissioner Makary has suggested that the information in CRLs is actually FDA’s thinking (rather than the sponsor’s or a combination of both), and that publication of CRLs will help equip other future drug developers with information on which they can rely. In Commissioner Makary’s view, releasing CRLs will also help the public understand FDA’s reasons for refusing to approve a drug, and bring more cures and treatments for Americans by allowing companies to learn from others’ mistakes.⁶

Release of Previously Unpublished CRLs Notwithstanding FDA’s Regulations

The agency’s release of 89 CRLs lays down a marker that FDA, in fact, means to release CRLs for unapproved drugs. The released letters were all recent — all had been sent since 2024 and were typically less than one year old. In addition, many of the released CRLs appear to pertain to applications for which sponsors still have time to challenge FDA’s determination that the application is not approvable — or for which sponsors may intend to resubmit the relevant application. In fact, some of the letters are less than six months old and concern applications that sponsors have publicly stated are under ongoing development and plans to resubmit.

FDA’s release of CRLs in real-time, and in cases of failed or abandoned products, is unprecedented, even if much of the data and information found in the CRLs is appropriately redacted. Sponsors often keep even the existence of a New Drug Application or Biologics License Application confidential, often publicly disclosing only as approval nears. Indeed, FDA’s regulations specifically promise that “FDA will not publicly disclose the existence of an application or abbreviated application before an approval letter is sent to the applicant.”⁷ FDA has long respected this confidentiality, refusing to publicly issue information regarding pending applications.

FDA did redact the recently released CRLs, as it promised it would, for confidential commercial information, trade secrets, and personal private information. Our analysis indicates, however, that the CRLs were not always consistently redacted, and that some still reflected sponsors’ confidential information, again in spite of FDA’s regulatory requirement not to release this information.

A New Era of Transparency With Significant Business Implications

The public release of CRLs for unapproved drugs ushers in a new era with serious business implications. For example, our review found that nearly all of the newly released CRLs cited manufacturing or compliance deficiencies as one of FDA’s concerns. Although FDA redacted many of the specifics of these concerns prior to publication, even disclosure of the existence of manufacturing or quality control concerns could significantly impact customer and investor views of a sponsor. Several of the CRLs also revealed FDA’s inspection findings with respect to a sponsor’s facilities. Even though the substance of these inspections was largely redacted, without adequate context, this disclosure could give rise to misperceptions about the operations of the sponsor or its contract manufacturer.

As a practical matter, now more than ever, sponsors will want to clearly designate sensitive confidential information and transparently request confidential treatment. Likewise, sponsors will need to pay careful attention to their discussions with and submissions to FDA and be aware that those discussions may be reflected in a released document; they’ll want to have a clear, written record of any corrections or objections.

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In light of these real-world impacts of the FDA’s new release policy, and FDA’s existing confidentiality regulations, it seems like a court challenge is only a matter of time. In addition to possible litigation, we will keep an eye on trends that emerge and how those trends translate into reliance by future sponsors or competitors. If you have any questions or would like more information, please reach out to one of the authors of this Advisory or your existing Arnold & Porter contacts.

© Arnold & Porter Kaye Scholer LLP 2025 All Rights Reserved. This Advisory is intended to be a general summary of the law and does not constitute legal advice. You should consult with counsel to determine applicable legal requirements in a specific fact situation.