He’s now a prominent campaigner for the acceptance of cannabis as a vital medicinal product, and leader of Project Twenty21; the biggest medical cannabis patient trial in Europe, which aims to engage 20,000 patients by the end of 2021.

The project is spearheaded by the body he founded to drive independent research into drugs, Drug Science.

Its aim is to gather the evidence which will convince policy makers and prescribing bodies of the need to bring medical cannabis into greater use – something which still has not happened, despite the law changing on November 1, 2018, to allow cannabis-based products to be available on prescription. 

“Like most other people, we thought the job was done when the Chief Medical Officer said that cannabis, of course, is a medicine and the Home Secretary moved it from schedule one to schedule two, and then we thought we could move on to campaigning on other drugs,” says Nutt.

“But after a few months, it became clear that nothing was happening. And we got more and more irritated, like many parents and patients, and we thought, ‘What can we do?’ If other people aren’t going to get on and do it, then maybe we can. This is the vision of Project Twenty21.

“The rest of the world is so far ahead of us, it’s embarrassing. Our aim is for NICE and other regulators, expert groups, consensus groups and guideline groups to come to the conclusion that we have already come to – that cannabis is a medicine and it works.”

Within the first few hours of the project being launched in November, 4,000 people had signed up.

As well as offering the opportunity to patients with conditions including chronic pain, epilepsy and MS to try cannabis treatments, the project will cap the prices of medicine at £150 per month, far less than many people who are able to secure a prescription are currently forced to pay. There is also provision for 1,000 free treatments to ensure the trial is as inclusive as possible.

The project is backed by the Royal College of Psychiatrists, British Pain Society, United Patients Alliance, three medical cannabis companies and a host of experts and campaigners.

Nutt is all too aware of the ongoing controversy surrounding cannabis – a factor he attributes to being ‘largely’ the reason for his dismissal from his government post in 2009 – but is committed to changing the stance of the medical profession.

“Every doctor knows that every time you prescribe any drug to any patient, you are doing an experiment. I believe there is no medicine in the medical world that you can guarantee will work when you prescribe it. So every time you prescribe, it’s an experiment.

“And how do you judge the efficacy? You look at outcomes in that patient, because that’s what you care about. So that’s what we’re doing here. We will get clinical effectiveness data and will look at adverse events.

“We know that one of the great concerns that many doctors have is that these drugs are viewed as being very dangerous – this comes from doctors and other people telling the world that this is the case, even though they don’t know, because that’s what the government’s told them to do.

“It’s very difficult when you have 50 years of telling the world that cannabis is illegal because it’s a very dangerous medicine. It’s quite hard to change that mindset. That narrative becomes quite entrenched, particularly among older people, older doctors.

“But we think if we collect good data on adverse effects, we will be able to bust this bubble of hysteria around the claim that it’s going to cause schizophrenia.”

As well as the evidence on medical benefits it is hoped the trial will collect, Nutt also points to the vast cost savings for the NHS that can be made.

“It seems to us from what we can do in other countries that medical cannabis is going to save the health service a lot of money. We have examples of single patients saving their NHS Trust £20,000 a year through buying their own medicine, and those examples will be found across the country,” he says.

“It’s currently relatively expensive, and then there is the absurd bureaucracy that’s been built up to actually prevent people getting access to this ‘dangerous’ drug. We are beginning now to get governments to understand the human costs involved, for example, the cost of being a carer is vast. This can help show that cannabis is an extremely cost-effective approach to many disorders.

“We are working with Martin Knapp, Britain’s expert on the value of medicine, he is helping us design the protocols to make sure we can get the right economic outcomes to finally put the nail in the coffin of the idea that medical cannabis is going to break the NHS.”

As well as changing perceptions and policy alike, Nutt is determined to save desperate patients from resorting to the drastic measures many currently are being forced to take.

“If you’re not getting it prescribed, which most people aren’t, then you are breaking the law. You’re going to the black market, and that has a number of very, very serious problems,” he says.  

“You can get arrested. There are court cases still going on with people who are using legal cannabis, it’s outrageous, a complete waste of taxpayers money, but it’s happening.  

“Worse than that you don’t know what you’re getting. Because there’s no quality control. you’re exposed to people who are often rather unpleasant and potentially dangerous. You may get contaminated products. So it’s not just a failure of medicine. It’s also making things worse because you’re forced into a very difficult and dangerous underworld.

“Medical cannabis is still out of reach for far too many. Patients don’t deserve any of this, and the situation with prescribing desperately needs to change. Through Project Twenty21, we hope to work towards achieving that.”

Profesor Nutt was addressing an audience at an event hosted by the Medical Cannabis Clinicians Society in London.