London conference pushes uses ranging from reducing pain to increasing orgasms • Cannabis capitalism: who is making all the money?

In a Mayfair hotel ballroom some of the UK’s biggest banks and pension funds have gathered to consider an investment in a new wonder ingredient that promises to revolutionise products ranging from pharmaceuticals, face creams and diet supplements to yoghurt and beer.

That ingredient is cannabis, and it has exploded into a multibillion-dollar industry as countries relax rules on its medical and personal use.

It has also become a serious investment proposition. The global cannabis industry has gathered in London this week for Europe’s largest marijuana investment conference, Cannabis Invest, with bosses of industrial-scale weed growers hoping to tap UK investors for fresh funds to drive expansion plans.

Cannabis capitalism: who is making money in the marijuana industry? Read more

From 17 October, Canada – which led the way in legalising prescription cannabis in 2001– will allow the sale of all recreational marijuana. “It’s been too easy for our kids to get marijuana – and for criminals to reap the profits,” Canada’s prime minister, Justin Trudeau, said on Twitter when the legislation passed. “Today, we change that.”

Companies are now preparing to flood the market with a wave of innovative products as well as the more traditional seven-fingered leaves. The bosses of Canada’s cannabis companies – which have grown from nothing to multibillion-dollar enterprises in less than five years – claim the industry will soon be bigger than the beer trade.

Nav Dhaliwal, chief executive of wholesale company Supreme Cannabis, said: “Cannabis is an emerging global market, and our thesis is we are at the beginning of a global rollout.

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“We estimate that the market will be worth $180-200bn a year over the next decade just for medical use, and cannabis will expand beyond medical use. From pharmaceutical companies to alcohol to tobacco – cannabis is a threat to all of these industries.”

Research by Prohibition Partners, a cannabis industry research firm, estimates that £8bn changes hands in black market cannabis in the UK alone, but legalised the industry could be worth £16.5bn a year by 2018, meaning UK consumers would be spending four times as much on marijuana as they currently do on bread.

“Make no mistake, this is going to become a large global industry – bigger than global brewing,” Cam Battley, chief corporate officer of Edmonton-based Aurora Cannabis, told investors at the MayFair Hotel conference. “And, I’ll tell you why. Beer has no legitimate medical applications, no matter what we tell ourselves on a Friday evening.”

Battley, who spent most of his career at established pharmaceutical firms, said cannabis has been proven to be effective at treating symptoms of a wide range of diseases and conditions, including multiple sclerosis, cancer, HIV/AIDS, epilepsy and arthritis.

Aurora, which has expanded from 35 staff when Battley joined in 2016 to 1,500 today, supplies medicinal cannabis to 350,000 Canadians. The value of the company, which has capacity to grow 430 tonnes of cannabis a year and is listed on the Toronto stock exchange, has soared from C$70m (£42m) in 2016 to C$11.8bn (£7.1bn).

Values have soared at other cannabis companies, as investors expect huge growth in the market. Shares in rival producer Canopy Growth, which is listed on the Toronto stock exchange under the ticker WEED, have increased sixfold in the past year. Constellation Brands, the owner of Corona beer, bought 35% of Canopy this summer for $4bn. Canopy, the biggest player in the market, is now valued at C$14bn – making it worth twice as much as Marks & Spencer.

“There is a global mega-trend under way and the leading edge is medical, but it will rocket further when consumer products come online,” Battley said.

“It’s my hope that the UK will become one of the global leaders in Cannabis,” Battley told the British investors. Cannabis is still illegal in the UK, but Battley said he hoped that public outcry over the the case of Billy Caldwell, a 12-year-old boy with severe epilepsy who was denied access to the cannabis oil he used to manage his condition, would help speed up legislative changes here. Sajid Javid, the home secretary, said in July that doctors would be able to prescribe cannabis-derived medicinal products by the autumn.

“We are in a hopeful moment,” Battley said in reference to the Caldwell case. “There’s money to be made and a lot of it. This is going to be big, you’ll look back at this as a turning point in your investment.”

Battley said the most exciting thing about cannabis as a product is the “remarkable number of routes of delivery”. “How many ways can you drink a beer?” he asked the assembled crowd of 200 or so investors. “Cannabis can be inhaled – we all experimented with that in college – it can also be drunk, eaten and applied topically [on the skin],” he said.

Battley said cannabis can also deliver a greater range of experiences than beer, because its 483 compounds can be combined in different ways to produce different experiences. “Beer will get you drunk,” he said. “Cannabis is a different kind of animal. One combination may deliver a stimulating uplifting effect perfect for a night out with friends, another may make you relaxed and be perfect for a night in at home binge-watching a TV series. Another, may be perfect for a romantic evening with your partner.”

Other companies are promising to exploit the latter – in lubricants which claim to help eight in 10 women achieve better orgasms.