According to reports by both Ring Magazine and the Los Angeles Times, Canelo failed two tests for clenbuterol on February 17 and February 20. Since then, Canelo has passed two tests administered by the Voluntary Anti-Doping Agency (VADA) on March 2 and on March 5.
Coincidentally, March 5 was the date when Canelo's failed drug test came to light in a press release sent by Golden Boy Promotions, the company founded by Oscar De La Hoya that promotes Canelo. The press release said Canelo's failed drug tests came as a result of him consuming contaminated meat in Mexico, where clenbuterol is present and legal, unlike in the United States.
The press release included comments by both the boxer and Daniel Eichner, Director of SMRTL, the lab accredited by the World Anti-Doping Agency (WADA) that conducted the two February tests. Eichner stated the levels of clenbuterol present in Canelo's system were consistent with those of someone who consumed tainted meat, but the initial press release did not mention the dates the tests were conducted. Canelo's camp has already moved away from Mexico and into the United States earlier in the week.
Since the announcement was first made, both the WBA and WBC have publicly come out in defense of Canelo. The Nevada State Athletic Commission is currently investigating the matter, but so far, the fight appears to be moving forward as scheduled. The fight, a rematch from their controversial first fight in September that ended in a draw, is scheduled to take place on May 5 at the T-Mobile Arena in Las Vegas.