Medical experts are warning against a European Directive which they claim will seriously jeopardise research in areas such as cancer.
Research costs may go up
The aim of the new law - which member states are due to adopt in May - is to improve safety by standardising clinical trials.
But researchers say increased red tape will send costs of vital clinical trials soaring.
More than 2,000 researchers have signed a petition against the measures.
They are concerned that the directive was designed only with big pharmaceutical companies in mind.
And they warn that medical charities - who often work on a shoestring - may not be able to cope with overbearing bureaucratic demands.
Dr Richard Sullivan, from Cancer Research UK, said the directive had been developed over the last 10 years - but academics had not been widely consulted.
"Our problem with this directive is simply that the bureaucracy of a lot of elements within the directive is going to outstrip any potential protection for patients."
His view was echoed by Dr Brian Moulton, of the Save European Research Campaign.
He said: "Our concerns are that the directive has made the environment too tough for academic and investigator-led research.
"It has created a set of circumstances and working conditions which people who are trying to carry out research in this arena will find too difficult.
"And unfortunately it will probably stop a lot of very important research going forward."
Opponents of the new directive say it will mean that research previously carried out by one hospital consultant and a nurse will require two consultants and two or three nurses just to cope with the paperwork.
In a statement the European Commission said the potential hurdles to research had been considered when the plans were being discussed between member states last year.
"It is not the intention of the Commission that the implementation of the clinical trials directive in national law should have a prohibitive effect on prospects for European research.
"On the contrary, it is the Commission's intention to strengthen a European clinical trials environment in the interests of the European Research Area and the European citizen."
A Department of Health spokesman said: "We are determined to ensure the UK regulations place as little undue burden on academics as possible, while at the same time ensuring we have the safest possible regime for clinical trials.
"There should be no unnecessary obstacles blocking research which contributes to saving lives. We are surprised by today's comments, especially as we have been very careful to ensure that the academic research community has been fully consulted throughout the process."