The Voluntary Anti-Doping Association (Vada) has announced an “adverse finding” in a test on Browne.
He served a six-month ban for testing positive for clenbuterol after beating Ruslan Chagaev in March.
The unbeaten 37-year-old, third in the WBA rankings, was later ruled “unlikely” to have taken that drug deliberately.
Browne was scheduled to fight Shannon Briggs, of the USA, for the vacant WBA world heavyweight title before the end of the year.
His management, Hatton Promotions, describedthe failed test as “hugely disappointing” and a “bitter blow” after the fighter “fought so hard to clear his name” earlier this year.
The World Boxing Council, which has started an investigation after being notified by Vada, said Browne can request his B sample be tested.
Browne, who has won 21 of his 24 fights by knockout, had gained the WBA title by beating Uzbekistan’s Chagaev but was then stripped of it following the positive test for clenbuterol after the fight.
Clenbuterol is a powerful drug used to treat asthma, but it can also help build up lean muscle mass and burn off fat.
Browne was reinstated in the top five of the WBA rankings on his return to the sport in September.
Browne’s management said it would investigate his daily supplements and prescribed medication and said his voluntary entry into the WBC clean boxing programme was not the “action of a man who wishes to intentionally take performance enhancing drugs”.
Source: BBC news