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# Cell2in Asks FDA OK for Glutathione Monitoring for BLAs
- URL: https://www.fdaweb.com/cell2in-asks-fda-ok-for-glutathione-monitoring-for-blas/
- Published: 2020-05-26T12:00:00.000Z
- Updated: 2026-09-14T16:15:55.000Z
- Author: David McFarland
- Tags: Biologics, #legacy-id-D5146859

In a 5/20 petition, Seoul, Korea, biotechnology company Cell2in is asking FDA to update applicable guidances to identify real-time glutathione monitoring methods as an acceptable means of measuring potency for purposes of submitting a BLA for cell-based therapies, including stem cell therapies. The [petition](https://www.regulations.gov/contentStreamer?documentId=FDA-2020-P-1416-0001&attachmentNumber=1&contentType=pdf&ref=fdaweb.com) says it is focused on the critical quality of potency and says it is not possible to overstate the importance of assessing a cellular therapy product’s potency.

“Without an accurate assessment of potency,” the petition says, “there is simply no guarantee that the product will have the desired therapeutic effect in patients.”

Cell2in says it is identifying a method for real-time monitoring of intracellular glutathione in living cells as an assay that cell-based therapy researchers and sponsors can use to measure product potency. The petition says the assay uses intracellular glutathione as a proxy for cells’ antioxidant capacity, functionality, and “stemness” (a measure of stem cells’ ability to self-renew, proliferate, and differentiate) without consuming the cells’ glutathione.