Fairfax Media has confirmed the ''professional footballer'' references in the December 2012 AOD-9604 patent application lodged by Metabolic Pharmaceuticals related to four Essendon players.

The revelation comes as Calzada Limited, the ultimate holding company, on Monday admitted it received case notes on 25 people using AOD-9604 from former Essendon sports scientist Stephen Dank. These 25 people included four Essendon players.

It is understood Dank removed all identifying details from the information he passed to the company. The players were unaware that Dank's observations about how their bodies responded after they used a cream containing AOD-9604 had been passed to the company developing the drug.

A source aware of Dank's role in passing on the data said the players were not informed because their identities were not disclosed.

In a statement to the Australian stock exchange, Calzada said it became aware in late 2010 of Dank's involvement in the ''legal (where prescribed by a registered doctor) use of AOD-9604 including weight loss, anti-ageing and the treatment of soft tissue injury''.

In September last year, the company said Dank agreed to document case notes on the use of AOD-9604 and two months later he provided details from 25 people who used it to lose weight, body sculpt and for soft-tissue injuries.

''These notes only record historical anecdotal information about the biological function of AOD-9604. In no way do these notes constitute a clinical trial,'' the company said.

AOD-9604 is not approved for human therapeutic use in Australia, although people may use the drug for medical reasons under the guidance of their doctor. It is banned by the World Anti-Doping Agency, and the Australian Sports Anti-Doping Authority is investigating whether Essendon players were used as guinea pigs.

Fairfax Media reported on Saturday that a Metabolic Pharmaceuticals patent application lodged in December 2012 described the drug's impact on injured footballers. The patent application referred to AOD-9604's use in four ''professional footballers'' to expedite recovery from injuries.

Dank was liaising frequently with Metabolic Pharmaceuticals chief executive David Kenley while working with Essendon.

Mr Kenley never paid Dank for his efforts aimed at building an anecdotal case that AOD-9604 could be used to help people recover from injury.

In early 2012, Dank arranged for Mr Kenley to give Essendon coach James Hird and then chairman David Evans a financial briefing on the company. This was in Mr Evans' capacity as the owner of a stockbroking firm.

Trading in shares in Calzada was halted on Monday.

Essendon said last night that its club doctors had examined the MRI reports in the case notes and concluded they were ''inconsistent'' with those of its players.