The number of primates used in medical research in the UK is set to rise significantly in the coming years.
The scientific community has acknowledged as much - and the animal rights lobby is convinced of it.
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As science seeks to tackle the neurological diseases afflicting a "greying population", it is said we will need a steady supply of monkeys on which to test the safety and effectiveness of the next-generation pills.
Experts say the extremely specific way these novel pharma products will work means primates - because their brain architecture is very similar to our own - will be the only animals suitable for experimentation.
This whole area of research is, of course, a very contentious one. We - humans - are also primates.
It is fair to argue there are ethical dilemmas related to primate studies that one does not have to grapple with in, say, mice or rats, which far outnumber monkeys in the lab.
Now, though, the thorny topic of primate research is about to take on a major political dimension, too.
The First Secretary of State, John Prescott, must decide shortly whether to give the go-ahead to Cambridge University to build a new animal-testing facility in the city.
Local planners have already thrown the request out twice - they fear the policing costs and disturbance that will accompany the expected animal rights protests will be more than city residents can bear.
But the direct intervention of Prime Minister Tony Blair and his chief scientific adviser in support of the application means the issue has gone right to the top of government for a final decision.
"I would be staggered if John Prescott went against the decision of Tony Blair," said Wendy Higgins, from the British Union for the Abolition of Vivisection (Buav).
"The decision will be a political one; it won't be one about planning - and it certainly won't be one about science or ethics."
If approval is given, the construction site at 307 Huntingdon Road in Cambridge will almost certainly become the focus for sustained demonstrations - and quite possibly the target for the type of direct action that so concerns local planners.
Nonetheless, Professor Roger Lemon, the director of the Institute of Neurology at University College London, says the Cambridge proposal must go through.
"If it were not to go ahead, it would be a signal to the whole medical research community that new developments were no longer possible - not just the Huntingdon Road development.
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"It would effectively be a signal that would block any new animal-research facility for the foreseeable future. It is a turning point," he told BBC News Online.
About three-quarters of the procedures done on primates in the UK are toxicology tests to check the safety and efficacy of new drugs. Immunology experiments, such as for the development of new anti-malarial treatments, are on the increase.
But fewer than 100 monkeys a year, Lemon says, are subjected to the headline-grabbing and highly invasive neurological procedures that result, ultimately, in death.
For whose benefit?
It is work, however, that he will defend because of the impact animal studies have had on human healthcare.
He points to the very successful deep-brain stimulation techniques for Parkinson's sufferers that have now benefited about 20,000 patients worldwide, and the new stroke therapies that have come out of our understanding of how the brain can reorganise itself after injury.
"Non-invasive brain techniques in humans have been hugely successful - techniques such as Pet, fMRI, transcranial magnetic stimulation," he said.
"These are all critically dependent on our understanding of the anatomy and physiology of the brain and this came from animal data. If we were to stop now, we would halt the development of yet better and more sophisticated techniques."
The government's watchdog in this area, the Animal Procedures Committee (APC), recently released a report on primate use.
It called for greater efforts to be made to find alternatives. These included doing more preliminary tests on new compounds in donated human tissues, and in human volunteers themselves at very low doses.
There are many in the pharma sector who believe certain tests, such as those that investigate the effects of overdose, are no longer necessary; the data can be acquired in different ways.
"We in the UK are very much on board for this," one toxicologist in the field told BBC News Online. "But it would mean relaxing the laws. We haven't had a thalidomide disaster since the 1960s and the regulators are very nervous about exposing human health to greater risks - especially in the EU."
Hearts and minds
The animal rights lobby believes such measures would amount to mere tinkering anyway and have no support in government which it says holds non-animal alternatives in utter contempt.
It rejects the scientific validity and relevance of primate studies and says it is time the UK washed its hands of the practice.
"There are fundamental differences in the structure of human and non-human primate brains," Buav's Wendy Higgins said.
"There isn't similarity in all cases in different sub-species. In one Parkinson's disease model we reported on, the animal was continually circling - going around and around.
"Human Parkinson's sufferers don't do that but things like this are simply overlooked or it is hoped they can be factored out of the results."
If 307 Huntingdon Road is approved, expect a ferocious public relations battle. Both the animal rights lobby and the scientific community intend to make a stand on the issue.
"Let's be clear, we're not talking about a cure for baldness here," said Dr Alastair Kent, of the Genetic Interest Group, which represents families with disease.
"We're talking about horrendous conditions - Parkinson's, Alzheimer's, schizophrenia and the like - which blight the lives of those people that have them and their families who have to look after them.
"Of course we must do everything to eliminate unnecessary suffering but at the end of the day, it's a stark choice: it's your child or a macaque. You make your choice and you live with the consequences."