US sprinter Erriyon Knighton was handed a four-year ban after testing positive for which banned substance?

Erriyon Knighton, American sprinter and 2023 200m World silver medallist, received a four-year ban for violating anti-doping rules. He tested positive for Epitrenbolone, an anabolic steroid, during a May 2024 out-of-competition test. Initially cleared by a US tribunal citing possible meat contamination, the ruling was overturned after WADA and World Athletics appealed. The Court of Arbitration for Sport (CAS) upheld the ban, disqualifying his results from March 26 to April 12, 2024, and making him ineligible for the 2025 World Championships in Tokyo.