In this time of modern technology and scientific gains, we have no justification to torture other sentient beings that inhabit this earth. We share the earth with all it's creatures. We are not here to dominate and use animals as though they are objects. They feel pain, sorrow and all the emotions that we do. The fact that they animals are a different species does not give us a right to use them as we please. This is an archaic practice that can only be called a product of ignorance.
Although animal research may not be the best possible way, it has saved countless human lives in avoiding dangerous experiments. Some animals even have similar organs to humans, allowing for better testing. In the future, the scientific breakthroughs acquired through animal research may even save other animals or make that research entirely unnecessary. For now, instead of experimenting with a human guinea pig, it's better to use an actual guinea pig.
Many scientific breakthroughs have resulted from animal testing, particularly the testing done on primates and rats. Testing on animals with genetic similarities to humans has the potential to cure illnesses and develop other medical breakthroughs. When animal testing offers the chance to save human lives, it should be done. However, it should not be done for other reasons, such as testing of cosmetics.
Drugs that have helped to control a wide ranges of diseases in humans were first tested in animals to ensure no serious negative impact. Many prospective drugs do not meet approval standards for safety in humans because of negative impacts on animals. If animal research is banned, then it creates the risk of much higher numbers of negative drug responses in humans.