Plans to share patient records with private companies "rings alarm bells", the Shadow Health Secretary Andy Burnham has said.
Prime Minister David Cameron is expected to announce the government's desire to open up the NHS to private healthcare firms today.
"The end-game is for the NHS to be working hand-in-glove with industry as the fastest adopter of new ideas in the world," he will say.
A £180m funding pot is also due to be unveiled to help commercialise medical breakthroughs and consult on an "early access scheme"- aimed at putting new drugs in NHS on a quicker basis.
The plans include the sharing of anonymous patient data in the hope it will speed up the development of new treatments.
Government officials claim patients are not in any danger of being identified or tracked through their records, but campaigners have publicly slated the proposals, fearing commercial interests are being put before patient privacy.
Speaking to Sky News, Burnham said he was concerned one of the patients' groups that was on the working group looking at this issue of creating closer ties between the NHS and the private sector has "walked away".
"That gives real cause for concern and rings alarm bells," he said.
"The Government simply can't say: 'This is all red tape and it all must be brushed away'.
"Proper regulation, essential safeguards need to be in place when it comes to the use of patient data."
Dr Vivienne Nathanson, Head of Science and Ethics at the British Medical Association, said while the proposals to share anonymised health data would benefit patients, they could also "undermine patient confidentiality".
"We are especially worried by recommendations that would grant researchers, possibly from large commercial companies rather than the patient's healthcare team, access to patient records," said Dr Nathanson.
"This could mean that details of an individual's health status and treatment will be revealed if researchers are able to search through records and identify patients in order to contact them.
"The BMA will be examining these proposals carefully. We believe that patient records must be kept confidential and be anonymised if they are to be used for research purposes unless explicit patient consent has been obtained."