The National Health and Medical Research Council has granted a group of medical researchers more than $1 million to conduct the trial of lisdexamphetamine, a substitute for amphetamines.

Researchers from  the University of Sydney, UNSW and the Australian National University, will next year conduct a clinical trial of about 240 people who are heavily dependent on crystal methamphetamine, or ice, over four years.

Lead investigator, University of Sydney clinical professor Nick Lintzeris​, said: "This is certainly the largest study proposed in Australia for methamphetamine dependence ... Should this prove to be an effective treatment, we're confident this could be quite easily disseminated in normal clinical practice."

The proportion of Australians who use amphetamines remains about two per cent, but the number of those who are heavily dependent on crystal methamphetamine has grown significantly in the last decade.

Two-thirds of heavy ice users stopped taking the drug in the long term, or reduced the amount they used in the short term after they received psychological treatment. But counselling was not effective for the remaining one-third of severely dependent users.

Lisdexamphetamine was a modified version of another amphetamine substitute, known as dexamphetamine, which has been trialled on 50 people at St Vincent's Hospital in Sydney as part of a smaller-scale pilot study. Dexamphetamine had also previously been used to treat weight loss, narcolepsy and attention deficit hyperactivity disorder (ADHD).

Professor Lintzeris said that it was unlikely this could be taken in the community, because of concerns dexamphetamine might be sold on the street or injected, rather than taken orally, making it expensive and inconvenient for users.

Lisdexamphetamine only became active once it was absorbed in the blood stream. "That greatly reduces the risk of misusing it [because] if someone is injecting it, there is no other advantage or no additional high," he said. "So we are far more confident in its ability [to be used[ without a close level of supervision."

"This reduces the cost, inconvenience for patients, and if it is convenient they are more likely to stay in treatment."

The effects of Lisdexamphetamine also lasted longer than its predecessor, which gave users a "sped up" feeling, with a better appetite, yet wore off over the course of a day, leaving them lethargic.

They will study the impact of the drug on ice users from Adelaide, Sydney and Newcastle over 12 weeks.

The hospital's clinical director, Dr Nadine Ezard​ likened the capsule to a nicotine replacement therapy for smokers, rather than a lifelong treatment: "We're hoping if this medication works, it will offer a treatment for methamphetamine dependency before people run into severe problems."

All participants will all be given psychological treatment, but only half will be given lisdexamphetamine. The other half will be given a placebo.

It comes ahead of the Turnbull government's Ice Taskforce findings, which are expected to be made public in coming weeks.

The Council will announce funding for the trial on Monday, which is among 836 research projects granted $630 million this year.

Professor Anne Kelso, its chief executive officer, said: "The research funded today is at the forefront of our knowledge of health and disease. These grants will support Australia's best new and established researchers working throughout the health and medical research sector."

Health Minister Sussan Ley said the Council had granted about $122 million for cancer research, $50 million for mental health research and $25 million for dementia research, among other medical conditions.

UNSW and Black Dog Institute researchers were also awarded $2 million to trial the drug ketamine - traditionally considered a party drug - as a treatment for depression.