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# More FDA ‘Stringency’ Seen on Accelerated Drug OKs
- URL: https://www.fdaweb.com/more-fda-stringency-seen-on-accelerated-drug-oks/
- Published: 2024-08-15T12:00:00.000Z
- Updated: 2026-09-14T14:38:28.000Z
- Author: David McFarland
- Tags: Drugs, FDA Policy/General, #legacy-id-D5157581

Two Sheppard Mullin attorneys say a recent untitled letter to Bristol Myers Squibb’s Mirati unit involving communications to healthcare providers on its Krazati (adagrasib) tablets that received accelerated approval to treat some lung cancers is a “cautionary tale to sponsors of accelerated approval drugs.” Writing online in a *National Law Review* [post](https://natlawreview.com/article/krazati-untitled-letter-cautionary-tale-cfl-promotion-accelerated-approval-drugs?ref=fdaweb.com), the attorneys say the letter suggests the CDER Office of Prescription Drug Promotion (OPDP) may take a more stringent approach to regulating CFL (communications consistent with FDA-approved labeling) claims for drugs approved under expedited pathways.

The Krazati [letter](https://www.fdaweb.com/fda-cites-krazati-provider-web-page/) faulted the company for making efficacy claims that FDA said could not be drawn from the single-arm trial that supported the drug’s accelerated approval.

The attorneys say that while it is not surprising that FDA would take a more critical stance toward efficacy claims for drugs receiving expedited approvals, a review of OPDP untitled letters does not show such a trend.

They note the letter says FDA received complaints about the provider Web page under its Bad Ads program and also said it was concerned because of the public health issues involved in the lung cancers treated by the drug. But, the attorneys write, that leaves unanswered the question of what initially prompted complaints about the promotional materials.

They suggest that FDA saw noncompliance with its CFL guidance as well as with its clinical trial endpoints guidance. “The CFL guidance makes clear that evidence used to support CFL promotional communications must be “scientifically appropriate and statistically sound,” the post says. “Adding to this, in the clinical trial endpoints guidance, FDA plainly states that while single-arm trials are capable of providing an accurate assessment of some endpoints (such as overall response rate), stable disease should not be a component of overall response rate and single-arm trials do not adequately characterize time-to-event endpoints such as overall survival or progression-free survival and a randomized study is instead necessary to evaluate such endpoints.”

The attorneys conclude that the untitled letter may demonstrate that the guidances are important not only for clinical trial design but also for predicting how FDA may evaluate post-approval claims and the underlying evidence to support CFL communications.