Colin Bettles: Grain Producers Australia boss breaks his silence as he prepares to return home after he was seriously injured on a San Francisco s heading work trip

An Australian business left fighting for life in the US on a work trip is looking forward to a pepperoni pizza after he was finally given the all clear to fly home.

Grain Producers Australia (GPA) CEO, Colin Bettles will return to Australia on Sunday after spending two weeks in a San Francisco hospital. 

Mr Bettles, who previously served as a media adviser to former deputy prime minister Michael McCormack, was found seriously injured and unconscious while on a solo work trip on July 4.

He was found with serious head and eye socket injuries and was rushed to the San Francisco General Hospital and Trauma Centre, where he spent five days in an induced coma.

After being discharged last week, Mr Bettles booked a return flight to Sydney, telling The West Australian that he 'can't wait to get home'.

He thanked the 'fantastic' hospital staff and his 'amazing' family and friends for their support and said that he is now 'slowly on the mend'. 

He added that he could not recall much of what happened the night he was out walking. 

'I don't have a very good memory of anything, I absolutely don’t remember the incident ... all I have on my phone is a picture of a nice pepperoni pizza [from beforehand], in that sort of area,' Mr Bettles told the publication.

Mr Bettles' friends originally claimed he had been beaten and mugged while returning to his hotel on foot late at night. 

But officers from San Francisco Police Department (SFPD) who are investigating the incident 'diligently' recently revealed they hadn't not found any evidence of a crime.

'SFPD reviewed surveillance video from the scene and found no indication that Bettles was assaulted or the victim of a crime. He was in possession of his property at the hospital,' a statement supplied to the publication read. 

 After friends and colleagues in Australia learned that Mr Bettles had been placed into an induced coma, the chair of the GPA board, Barry Large, sent his best wishes.

'There has been a significant amount of people in contact with us following news of Colin’s injuries and it shows just how much people respect and care for him,' Mr Large said.

'And rightly so, Colin is a great person and we hope this message provides some comfort.

'We will continue to support Colin and his family throughout his recovery and hope that he’s able to return to Australia soon.'

Mr Bettles' partner, who works in regional Australia with limited phone reception, only noticed something was amiss when he didn't board a plane to New York.  

She reportedly contacted Mr Bettles' friend of 15 years and former employer, Nationals MP McCormack, who raised the alarm with the Department of Foreign Affairs and Foreign Minister Penny Wong.

US authorities then tracked Mr Bettles down to his hospital bed where he was in intensive care for five days.

It's understood that Mr Bettles was travelling by himself but conducting business in his capacity as GPA chief executive.