Overcoming obstacles to developing new analgesics.

Despite substantial investment by the pharmaceutical industry over several decades, there has been little progress in developing new, efficacious and safe analgesics. As a result, many large pharmaceutical companies are leaving the area of pain medication. Nevertheless, the chances of success could increase if analgesic drug development strategy changed. To achieve such a paradigm shift we must understand why development of drugs for pain relief is so challenging. [ABSTRACT FROM AUTHOR]