He was scheduled to fight Yuki Sasaki in the main event at Bitetti Combat 6 on February 25, 2010, but it was announced on February 22 that he had withdrawn from the bout due to "personal problems". Later that day, it was confirmed that Filho would in fact be fighting Sasaki. Filho then failed to show for the event's weigh-in, forcing a last minute cancellation of his bout with Sasaki. Filho was scheduled to face Bellator Fighting Championships Middleweight champion Hector Lombard in a non-title bout on May 13, 2010, at Bellator 18, but Filho pulled out of the bout due to visa issues and was replaced by Jay Silva. Filho made his Heavyweight debut and defeated Chilean newcomer Daniel Villegas on June 4, 2010, via first-round submission due to strikes. Filho faced Denis Kang on July 17, 2010, for the Australian-based promotion Impact Fighting Championships. They fought to a draw. In what came as a surprise decision to many, Filho was invited to participate in the ADCC submission grappling championship in Nottingham, England. Filho withdrew prior to the event due to injury. Paulo fought Satoshi Ishii on September 14, 2011. The bout was ruled a draw. On October 19, 2011 Filho made the announcement he would be retiring from Mixed Martial Arts and may or may not fight at KSW. During an interview Filho stated the reason for his retirement was his long struggle with substance abuse, he regretted that he was so far from where he could have been in MMA. Filho returned from retirement to face former UFC fighter Dave Branch in the World Series of Fighting 2 event on March 23, 2013. Filho was dominated by Branch in every aspect of the fight and lost a unanimous decision. Filho fought Andre Muniz at the Bitetti Combat 19 event on February 6, 2014. He again lost via a one sided unanimous decision. Following Melvin Manhoef's knockout of Evangelista Santos at Gringo Superfight 10, Filho, who won their first outing by submission, entered the cage and challenged Manhoef to a rematch. Though Manhoef wasn't asked about the possible fight before the challenge, he later accepted, and GSF promoter Antonio Tolentino announced the rematch would take place in November 2014. Filho was expected to face Amilcar Alves at Fatality Arena 7 on September 21, 2014. However, Filho was pulled from the bout due to an apparent seizure. In an interview with MMAFighting.com, Filho stated that it was personal issues that prevented him from competing.