Hill, Elliott and Peña tested positive for cannabis. Winn tested positive for amphetamines.
Hill's first-round TKO victory over Klidson Abreu on May 30 was overturned to a no contest due to the violation. The 29-year-old undefeated light heavyweight prospect was suspended six months and fined 15% of his fight purse.
Elliott and Peña were each suspended 4½ months and fined 15% of their fight purse. The reduced suspension was due to their fights being taken on short notice. Elliott lost to Brandon Royval on May 30 on 12 days' notice, and Peña fell to Khama Worthy on June 27 on 18 days' notice.
Winn was suspended nine months and fined $1,800 in relation to his March 7 loss to Gerald Meerschaert at UFC 248.
All the suspensions are retroactive to the date of the positive test. Cannabis is prohibited under Nevada regulations "in competition," meaning the period beginning 12 hours before a contest and ending with the postfight drug test.
There were several other actions taken by the NSAC at its monthly meeting Thursday.
Jorge Gonzalez, who is signed to the UFC but has not yet debuted, had a temporary suspension extended following a positive drug test from Aug. 5 for several anabolic steroids, including the metabolites of drostanolone and stanozolol.
Ty Flores, who fought and lost to Dustin Jacoby on the Contender Series event on Aug. 4, had his temporary suspension extended after testing positive for metabolites of the steroid Turinabol (also known as DHCMT). He will have a disciplinary hearing at a later date.
Also at the meeting, two UFC fighters were granted temporary licenses following special hearings. Ryan Benoit and Roman Dolidze have a recurring issue with the long-term metabolite of Turinabol pulsing in their system in trace amounts, long after ingestion. Both Benoit and Dolidze have already been suspended by USADA, the UFC's anti-doping partner. Neither were facing a violation in Nevada, but the UFC wanted to get ahead of a potential issue.
Last year, USADA added a threshold for the presence of the M3 metabolite of DHCMT. If a test result is below 100 picograms per milliliter of the substance, it is no longer considered a violation, but an atypical finding -- provided there is no evidence of new ingestion or performance-enhancing effects. This is the exact situation that longtime UFC champion Jon Jones has dealt with, and the Nevada commission inevitably licensed him to fight.
Benoit and Dolidze will be granted temporary licenses to compete beginning Dec. 1 following a six-month period of bimonthly testing by USADA, which has already begun.