After a three-year reprieve, a new US paediatric study requirement kicks in on August 18, 2020. The US Food and Drug Administration Reauthorization Act of 2017 (FDARA) will apply to new drug applications (NDAs) and biologics license applications (BLAs). Meg Egan Auderset at Clarivate Analytics shows how sponsors must incorporate molecularly targeted paediatric cancer investigations into development programmes and submit results in applications for approval.