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# Regulatory Review Period for Zephyr Valve Implant
- URL: https://www.fdaweb.com/regulatory-review-period-for-zephyr-valve-implant/
- Published: 2021-07-07T12:00:00.000Z
- Updated: 2026-09-14T17:05:25.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5149653

*Federal Register* notice: FDA has determined for patent extension purposes the regulatory review period for Pulmonx Corp.’s Zephyr Endobronchial Valve Implant, indicated for the bronchoscopic treatment of adult patients with hyperinflation associated with severe emphysema in regions of the lung that have little to no collateral ventilation. The regulatory review period is 5,744 days, which includes 5,565 days that occurred during the testing phase and 179 days during the approval phase. To view the notice, click [here](https://www.govinfo.gov/content/pkg/FR-2021-07-07/pdf/2021-14482.pdf?ref=fdaweb.com).