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. 2022 Jan 13;126(3):391–400. doi: 10.1038/s41416-021-01696-0

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Fig. 2 — a Clinical trials found in the FDA public database (https://clinicaltrials.gov/). b Clinical trials identified in EMA (https://www.ema.europa.eu/en/human-regulatory/research-development/clinical-trials-human-medicines) public database.