iRhythm Technologies has announced that the US Food and Drug Administration (FDA) has cleared design updates made to its Zio AT device.
The Zio AI continuous monitoring system combines a wearable electrocardiogram (ECG) patch, named the Zio AT patch, with the ZEUS system, iRhythm’s AI-powered software for ECG analysis.
This latest update comes after the FDA issued a warning letter to iRhythm regarding the device, citing violations of the United States Federal Food, Drug, and Cosmetic Act. Following an inspection of the company’s facility in Cypress, California, the FDA identified additional violations with the system, referencing previous concerns raised in a Form 483 from 2022.
Made public in May 2024, the letter pointed to labelling issues, problems with quality systems, and delays in reporting adverse events, particularly relating to two patient deaths while using the device. iRhythm confirmed receipt via a Form 8-K. The company stated in response to the Form 483 that it had “already taken measures intended to address certain items identified by the FDA”.
Following this, the FDA outlined a detailed action plan for the company to follow, also prompting an investigation by the US Department of Justice. iRhythm’s CEO Quentin Blackford reported continued progress when it came to remediating the FDA warning letters in an August 2024 earning call with analysts. The company is currently awaiting a second 510(k) clearance related to the letters.
In the 21 October announcement, iRhythm’s CEO Quentin Blackford said: “We are pleased to have received this first 510(k) clearance in line with the sequence of how we submitted the first of two 510(k)s at the beginning of this year, and we look forward to hearing about our second 510(k) in the near future.”
The Zio AT device is designed to capture and send data on both symptomatic and asymptomatic heart events, continuously recording ECG for long-term monitoring. It is cleared for patients aged 18 years or older who may have no symptoms, or experience temporary issues such as palpitations, shortness of breath, or dizziness. The system secured Japanese regulatory approval last month.
Shares in iRhythm are up by 17.9% following the clearance, increasing from €56 ($60.6) at close on 21 October to €66 ($71.4) at market open on 22 October.
