Rats are the most widely used animals in the research laboratories of pharmaceutical industry worldwide. According to one estimate, between 3.4 to 3.7 million rats are killed annually in the research laboratories of pharma industry. These 'unpopular' animals are invariably used in 80 percent to 90 percent of all experiments. Often these experimental procedures, mainly invasive, are extremely painful and are conducted without anaesthesia. An issue animal welfare activists have been debating for some time is the relevance and methods of such trials on rats and mice. It is a fact that animal welfare acts in most developed countries do not adequately protect mice and rats. Accreditation of Laboratory Animal Care International has laid down standard procedures for monitoring and conducting animal experiments but rarely these are observed by the researchers. No doubt, rats and mice have highly developed central nervous system, feel pain and suffer from the stress of confinement. But studies in rats on heart disease, cancer and stroke have proved confusing because of the major differences in rat and human physiology. Tests of cancer causing agents in rats and mice agree only 70 percent and at the same time the cancer causing agents do not develop similar range of cancers in humans and rats. There are also several cases in which animal experiments are done by certain research institutions of questionable scientific merit.

As rats and mice differ markedly from humans in many respects, it would be highly improper to extrapolate the results from experiments on these animals to humans, some leading pharmaceutical scientists believe. While it will be impossible to altogether stop animal experimentation for pharmaceutical research, their numbers could be effectively brought down if certain non-animal research methods are adopted by pharmaceutical industry. In fact, scientists strongly think that safety tests using human cells are more accurate than animal tests. Cell and tissue cultures are already being used to screen anti-cancer and anti-AIDS drugs and also to test product irritancy. The AIDS virus was isolated in human serum and in-vitro methods are providing new insights into the virus effect on human cells. The National Disease Research Interchange of the US provides more than 130 kinds of human tissues to scientists investigating diabetes, cancer, cystic fibrosis, glaucoma and 50 other diseases. In the multicentre evaluation of in-vitro cytotoxicity tests, researchers from US, Europe and Japan tried 68 different test tube methods to predict toxicity of 50 chemicals such as aspirin, diazepam, nicotine, malathion, etc.In fact, UK-based Pharmagene Laboratories has already started conducting new drug development and testing only by using human tissues and computer technologies. With tools from molecular biology, biochemistry and analytical pharmacology, it will be much simpler and efficient for research based pharma companies to use human tissues for investigation of new drugs.