Novo Nordisk issued a response to an FDA warning letter that cited serious violations in how the company tracked and reported adverse drug events for several of its medicines.

Included in the violations was semaglutide, the active ingredient in Novo’s top GLP-1 weight loss medications Ozempic and Wegovy.

What did the FDA find during its inspection?

The agency’s warning letter stems from an inspection of Novo Nordisk's Plainsboro, New Jersey, facility conducted between January 13 and February 7, 2025.¹ Investigators found that the company failed to comply with postmarketing adverse drug experience (PADE) reporting regulations, which require drug makers to submit serious and unexpected adverse events to the FDA within 15 calendar days of becoming aware of them.¹

FDA identified three core failures, with the first being Novo Nordisk's internal procedures allowing adverse events to be rejected or cancelled if the person reporting them believed the event was unrelated to the drug.¹

This standard is inconsistent with FDA regulations, which require all adverse events associated with drug use to be reported regardless of whether a causal link is suspected. In one example cited in the letter, a consumer who suffered a stroke while taking liraglutide had their case rejected because they reported the stroke was unrelated to the medication.¹

The second failure according to FDA, is the company and its call-center contractors improperly invalidating cases due to alleged missing patient identifiers, even when those identifiers were present in source documents.¹

In one instance, a reported death in a patient taking semaglutide went unreported due to staff failing to capture an available patient identifier.

Novo’s third failure, according to FDA, included cases designated for medical review that remained unreviewed well beyond internal deadlines.¹ In one cited example, a report of suicidal ideation in a semaglutide patient was received in December 2024, but was not reviewed until February 2025, after FDA inspectors flagged it.

The FDA also found that Novo Nordisk's procedures required obtaining consent from reporters before conducting follow-up on adverse event cases, a requirement that has no basis in federal regulations and resulted in serious cases, including at least one patient death, going uninvestigated and unreported.¹

The agency says the findings point to systemic failures across the company's pharmacovigilance program and expressed concern that the violations likely extended beyond the products sampled during the inspection.¹

How has Novo Nordisk responded?

In a statement acknowledging the warning letter, Novo Nordisk says it’s been working to address the inspection findings since receiving the initial observations from FDA in February 2025, submitting a formal response in March of that year and seven subsequent updates to the agency.²

The company says the warning letter largely seeks additional detail on corrective measures already underway and did not raise new concerns.² Novo also emphasized that the letter makes no conclusions about the safety or quality of its medicines.

What are the next steps for Novo Nordisk?

Corrective actions the company plans to take, or have already taken include the following:

• Revising internal procedures to remove language tying adverse event reporting to causal assessments
• Transitioning safety case intake from contracted call-center agents to in-house healthcare professionals
• Building dedicated vendor management and quality teams
• Conducting a retrospective review of closed pharmacovigilance deviations dating back to June 2017

Anna Windle, head of clinical development, medical and regulatory affairs at Novo Nordisk U.S., says the company plans to address the warning letter's requests expeditiously. "We are confident that we will resolve the matters outlined in the warning letter to the FDA's full satisfaction," she said.

The company added that the warning letter is not expected to affect production or its previously issued financial guidance.

In its response, Novo Nordisk noted it also recently received a separate warning letter related to a manufacturing inspection at its Bloomington, Indiana facility, as well as untitled letters from the FDA concerning advertising for Ozempic and Wegovy.²

Sources

1. Warning Letter Novo Nordisk Inc. U.S. food and Drug Association March 5, 2026 https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/novo-nordisk-inc-717576-03052026
2. Novo Nordisk acknowledges receipt of Warning Letter and welcomes further dialogue with the US FDA Novo Nordisk March 10, 2026 https://www.novonordisk-us.com/media/news-archive/news-details.html?id=916514