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# Regulatory Review Period for Kyowa Asthma Drug
- URL: https://www.fdaweb.com/regulatory-review-period-for-kyowa-asthma-drug/
- Published: 2020-03-04T12:00:00.000Z
- Updated: 2026-09-14T16:05:45.000Z
- Author: David McFarland
- Tags: FDA Policy/General, #legacy-id-D5146239

*Federal Register* notice: FDA has determined the regulatory review period for patent extension purposes for Kyowa Hakko Kirin’s Fasenra (benralizumab), indicated for the add-on maintenance treatment of patients with severe asthma aged 12 years and older and with an eosinophilic phenotype. The review period is 4,127 days, which includes 3,763 days that occurred during the testing phase and 364 days during the approval phase. To view the notice, click [here](https://www.govinfo.gov/content/pkg/FR-2020-03-04/pdf/2020-04363.pdf?ref=fdaweb.com).