Experts are debating whether terminally ill patients should have the right to try out new drugs that have not completed safety checks.
Drugs go through a series of tests before approval
The US is currently considering allowing such a move.
Professor Emil Freireich of the University of Texas says patients should be allowed to judge the risks.
But US medical oncologist Dean Gesme told the British Medical Journal that to allow this could harm both individuals and science.
Human guinea pigs
In the US, the Food and Drug Administration has proposed expanding access to investigational drugs for patients with terminal illnesses after initial safety - phase I - trials but before final approval.
However, Dr Gesme, who works for the Minnesota Oncology Haematology Professional Association, points out that more than 90% of drugs entering phase I trials are found unacceptable.
And, of those approved, most provide incremental improvements rather than lifesaving treatments.
The allure of promising new drugs continues to engender false hope, he says, which may delay approval and erode the clinical trials system by substituting clinical enthusiasm and wishful thinking for evidence based medicine.
"False hopes for unproved drugs can also erode the clinical trials system by substituting clinical enthusiasm and wishful thinking for evidence based medicine," he said.
And he questioned who would bear the costs of open access to partially tested drugs of unknown benefit.
But Professor Freireich, a professor of Special Medical Education Programs, rejects these arguments.
He believes permitting expanded access to experimental treatments for patients with limited life expectancy could actually accelerate drug development.
"When patients are offered compassionate use of an experimental drug, their doctors have to collect information as systematically as in the research protocol."
This data about use of the drug outside trial conditions would assist in drug development, he argues.
He points out that most cancer patients are deemed ineligible for drug trials beyond phase I testing - these tend to enlist the healthiest patients at the earliest point in their disease to give the highest probability of a positive outcome to fulfil regulatory requirements.
"It is tragic that regulatory bodies have created a circumstance where people have to live in an aura of hopelessness even though they have the will, the resources and the ability to expose themselves to the risk of participating in investigational studies and to enjoy the potential for benefit."
Experts investigating a drug trial which almost killed six young volunteers at Northwick Park hospital in the UK in 2006 recommended some drugs may be best given to people who are already ill. In the UK, it is the job of the Medicines and Healthcare products Regulatory Agency (MHRA) to regulate medicines and medical devices.
An MHRA spokeswoman said: "Under the Medicines Act, what a doctor can do on an individual patient basis is import or prescribe unlicensed medicines if they deem that to be the best treatment for the patient."