Scientists have written to the Prime Minister and Health Secretary Andrew Lansley expressing their concern about drug failures and adverse drug reactions.
More than 10,000 people die every year from bad reactions to prescribed treatments and scientists are calling for a fresh approach.
The experts believe adverse drug reaction has reach "epidemic proportions" amid rising costs in prescriptions.
Drug testing on animals before they are used on humans is being partly blamed.
The letter claims many increasingly prevalent ailments, like Alzheimer's disease, diabetes, cancers and stroke, remain without adequate treatment.
An important factor contributing to these problems is the over-reliance of the pharmaceutical industry on the use of animals to predict drug behaviour in humans.
The letter, published in the Lancet, adds studies have shown animal tests frequently fail to translate to the clinic.
Scientist Tony Dexter, who runs a research lab in Cheshire and is a signatory, said: "A fundamental problem is that a rat is not a human.
"They are different sizes, have different metabolisms and have different diets, so using animals to predict effects on humans is difficult.
"Fifty percent of compounds that prove to be safe in rats prove not to be safe in humans, so it really is the toss of a coin."
The experts are now calling for the use of more human biology-based experiments where chemicals are tested on human cells to see how people might be affected by new treatment.
The annual costs of treating patients who have had bad reactions to their treatment is around £2bn a year.
It is believed millions of deaths could be prevented with the use of new technology available. Some 148 members of parliament have signed a notion is support of the proposals.
A spokesman from the regulatory body Medicines and Healthcare products Regulatory Agency said: "The use of non-animal testing has been extended wherever possible and the MHRA will continue to encourage this approach.
"It is very important to recognise that at present there are no laboratory methods available to totally replace animal testing of medicines."
In 2008, the European Commission estimated adverse reactions to treatment kill almost 200,000 EU citizens annually at a cost 79 billion Euros.
The news comes at a time when costs of new medicines are rising creating an ever-increasing burden on the NHS.