A GOLD Coast teenage driver who ran over and killed a good Samaritan who was trying to stop a robbery has lost his bid to have his time behind bars reduced.

Alexander Craig Wharton Kirke was sentenced to nine years jail in June last year for the manslaughter of Darren Pullar, and for attempted robbery, attempted burglary and two counts of assault occasioning bodily harm.

His parole eligibility was set at the halfway point - July 9, 2022.

Kirke was 17 when he and a group of friends tried to rob Mr Pullar's Broadbeach Waters neighbours in the early hours of Boxing Day 2016.

Mr Pullar attempted to stop the robbery and was run over by Kirke as the group made a getaway.

Kirke was caught by police about two weeks later at a service station on the M1 at Mudgeeraba.

Kirke told an undercover officer in the watchhouse cells "many lies" but ultimately admitted he was the driver and described Mr Pullar as a "human speed bump".

Now 19, Kirke applied to have his parole eligibility date moved forward because he had "served a significant period in custody for a young person".

"The sentence was manifestly excessive given three things - the basis of the manslaughter being a negligence basis, the extreme youth of the offender, being 17 at the time of the offence, and his plea of guilty - in the circumstances where the court had decided that a serious violent offence declaration was not warranted," Kirk's barrister Chris Wilson told the Court of Appeal.

But the Court of Appeal disagreed, with all three judges refusing the appeal.

Justice John Bond said in his decision reasons that the primary judge had taken into account Kirke's age and guilty plea during the sentencing process.

"(The sentencing judge) was entitled to regard the circumstances of the offending as providing a foundation for an exercise of discretion to delay the parole eligibility date," he said.

After sentencing, Mr Pullar's sister, Sharon Hunter, spoke outside the Brisbane Supreme Court about what a generous and loving person her brother had been.

"We've always believed whatever the sentence imposed, it would never be enough for the person who took Darren's life in such a brutal and callous way," Ms Hunter said outside court.

"Darren was a special person with a big heart.

"We are proud of his bravery in acting to protect others, despite such terrifying circumstances.

"He was funny, loveable and kind. He was a generous soul and much loved."

Originally published as Killer teen's bid to reduce sentence lost