Glowacki, who has won 32 of his 36 professional fights, failed a drugs test after his loss to Richard Riakporhe one year ago in Manchester.
His urine sample returned an adverse analytical finding for Boldenone which is listed under section S1 of the World Anti-Doping Agency (WADA) 2023 Prohibited List as an anabolic androgenic steroid.
Glowacki, who denied taking a prohibited substance, was provisionally suspended in April 2023 and his case was heard by an independent National-Anti-Doping Panel on October 31st.
Walcz-born Glowacki first won the WBO cruiserweight title in a thrilling contest against Marco Huck in New Jersey 2015 and managed one successful defence before losing to current heavyweight champion Oleksandr Usyk on points in 2016.
Glowacki had been granted a foreign boxer's license by the British Boxing Board of Control for his bout last January and was therefore bound by UK Anti-Doping regulations.
