There is a "desperate need" for more investment in dementia research, the Health Secretary has said.
The economic and social reasons to find a cure, or disease-modifying therapy, cannot be ignored, Jeremy Hunt said.
Speaking to more than 300 health and finance experts gathered in London to discuss the burden of dementia around the world, Mr Hunt said more must be done to dispel the myth that dementia is an "inevitable" part of ageing.
Last year the UK used its presidency of the G8 to host an international summit on dementia, which ended with experts setting a global ambition to find a cure by 2025.
Today delegates came together again for the first in a series of legacy events following the summit.
"This is a condition that we can defeat and that is what we chose to do at the G8 summit in December," Mr Hunt said.
"In December we set ourselves some very ambitious targets and today we are here to find concrete ways in how we deliver those, including how we find a cure or disease-modifying therapy by 2025, how we encourage investment in dementia research and how we attempt new sources of finance to support global dementia innovation.
"The UK Government is doing what we can. Since 2009 we have increased investment in dementia research from £28 million to £52 million and we are on target to increase research spending to £66 million by 2015.
"But globally we desperately need to see new investment flowing into dementia research.
"We know from detailed analysis done by the London School of Economics that there is an impelling case both for economic and social viewpoints. That research shows that if treatment were available to delay the onset of dementia by just 36 months, it would save us here in the UK £5 billion per annum.
"Currently few people understand what it takes to find a treatment and eventually a cure that works and is also safe. We know it is a fiendishly complicated process that is going to take co-ordination, investment, partnerships from across the many sectors and no doubt many failed attempts to get there.
"We need innovation in finance ... to enable cutting-edge research as well as identifying and removing barriers that are currently stopping us achieving this."
Earlier Alzheimer's Research UK announced a £100 million research campaign and the Medical Research Council (MRC) said it was undertaking the world's biggest study into dementia involving two million people.
Later the Prime Minister will say immediate action is needed to accelerate the development of drugs to tackle dementia.
David Cameron will warn that more must be done to address a "market failure" on dementia research and drug development. He is expected to pledge a new drive by the UK to discover new drugs and treatment for the condition.
The UK will look at how to bring forward specific proposals on patent extensions and how to give patients earlier access to new drugs, Mr Cameron will say.
"The truth is that dementia now stands alongside cancer as one of the greatest enemies of humanity," he will say. "In the UK alone there are around 800,000 people living with dementia, worldwide that number is 40 million - and it is set to double every 20 years.
"We have to fight to cure it. I know some people will say that it's not possible, but we have seen with cancer what medicine can achieve.
"We first need to tackle head-on the market failure perilously undermining dementia research and drug development. And we need investment in research, greater collaboration, better incentives for taking new treatments to market and earlier access to innovative new treatments for patients.
"We need to join up the dots and create a big, bold global push to beat this. It will take years of work but we have shown with other diseases that we can make progress and we will do so again."
The news comes as the new world dementia envoy, Dennis Gillings, warned that if global leaders do not incentivise businesses to invest in research, the ambition set by the G8 dementia summit to find a cure by 2025 will not be met.
Dr Gillings said: "Dementia is a ticking bomb costing the global economy £350 billion and yet progress with research is achingly slow. Research must become more attractive to pharmaceuticals so they will invest and innovate.
"Just as the world came together in the fight against HIV/Aids, we need to free up regulation so that we can test ground-breaking new drugs, and examine whether the period for market exclusivity could be extended.
"Without this radical change, we won't make progress in the fight against dementia."