No positive results to peptides have been detected in Victorian racehorses since testing began before last year's spring carnival.

Racing Victoria (RV) chief executive Bernard Saundry issued a statement on Sunday saying the state's governing body was vigilant in its pursuit of illegal drugs.

Saundry was responding to a report in Sunday's Fairfax Media that Victorian trainer Dean Binaisse was under investigation over his alleged purchase of the anti obesity drug AOD-9604.

The report said other trainers, including one high profile trainer, were also being investigated.

While he confirmed RV was investigating the claims regarding Binaisse, Saundry said he would not discuss specifics.

"We have had an investigation on foot into the allegations raised against trainer Dean Binaisse in today's Fairfax Media," Saundry said.

"That investigation remains on-going and we are not going to comment on the specifics of it at this time.

"It is important to note that we are conducting investigations on a daily basis into matters pertaining to the integrity of the sport.

"We're not going to substantiate the allegations made within the article regarding other racing figures, other than to reiterate that we conduct daily investigations into a range of integrity matters and we welcome any evidence that substantiates a breach of the rules by a licensed person.

"Racing Victoria has been testing for peptides since before the 2012 spring racing carnival and to date we have had no positive swabs returned."

Saundry said RV also had frozen samples which could be retested for new drugs if the need arose.

"We are continuing to refine our testing methodology for these new and emerging drugs and are working with laboratories here and abroad to ensure we remain best positioned to tackle this threat," he said.

"As part of our drug testing strategy, we have frozen samples dating back to 2005 and with that we have the ability to re-test samples as intelligence leads us to do.