In the ongoing quest for drug discovery the trend is slowly shifting away from the synthetic chemistry route which has been prevalent over the past two decades. Many pharmaceutical companies are now sourcing new leads for drug discovery from natural resources. Natural products constitute a significant proportion of drugs currently in use. Products such as amoxycillin, cefaclor, ceftriaxone and lovastatin, all derived from natural products, have had a huge impact on the pharmaceutical industry and were listed in the top 20 best selling pharmaceuticals in 1990 along with captopril and enalapril which resulted from leads provided by a natural product. A large percentage of new agents used in medical practice tend to be either natural products or derived from natural products. In 1991, 16 out of 43 and in 1992, 18 out of 43 new chemical entities introduced onto the world pharmaceutical market were natural product derived.
Australia's unique plants and marine organisms offer the potential to discover unique bioactive compounds which have therapeutic potential or which can be the basis for the further development of therapeutic compounds. A single new pharmaceutical product with a novel therapeutic action could gross annual sales worldwide in excess of $1 billion and could generate returns comparable to those of major export industries based on wool, wheat and coal.
Conservation of the biodiversity of Australia's rainforests and marine organisms is therefore not only wise from a scientific and ecological viewpoint but also economically justified.
The use of naturally occurring compounds in medicinal applications is not new - traditional medicines derived from natural sources have been used by indigenous people throughout history and by the Aboriginals for the last 40 000 years. Recently a bark extract, used by Aboriginals to relieve pain, was found to exhibit analgesic qualities superior to morphine. The Queensland Pharmaceutical Research Institute (QPRI), Griffith University, in collaboration with Dr Jack Carmody, an expert in the physiology of pain, conducted preliminary tests on the bark which indicated that a crude extract was as potent as morphine. Research into the nature of the active constituent is being pursued by QPRI.
Traditional medicines continue to play a significant role in modern-day pharmacology although western medicine requires the isolation of the active constituent of a Chinese antimalarial preparation known as Qinghaosu. Artemether has been introduced for the treatment of drug-resistant malaria. The Chinese have a long history of using herb medicines and have accumulated vast experience in the use of medical plants. Many Chinese medical centres offer both traditional and western treatments.
Natural products, as well as continuing to provide essential medicinal compounds, provide a basis for the development of synthetic ones. The abundant pool of untested natural resources can be assessed with advanced screening technologies.
The Queensland Pharmaceutical Research Institute was established by Griffith University in December 1990 to provide a vehicle for collaborative research between industry and academia and brings together researchers with special expertise in drug discovery for the purpose of engaging in industry-oriented research and development. This enables Queensland to participate in the growth of the pharmaceutical industry, an industry which is expected to earn Australia some $2 billion a year from exports by the year 2000.
In June 1993, a joint venture agreement was signed between Griffith University and Astra Pharmaceuticals Pty Ltd, a subsidiary of Scandinavia's largest pharmaceutical group - AB Astra of Sweden. Astra Pharmaceuticals agreed to invest $10 million over a five year period in the joint venture which will screen natural products from Queensland's reef and rainforests to discover potential new pharmaceutical agents. This joint venture with Astra - one of the world's fastest-growing pharmaceutical companies - is proof of the importance the pharmaceutical industry is placing on natural products.
The basic research in natural product chemistry and screening at Griffith University has received long-term support from the Australian Research Council. The resultant Australian-developed technology, as well as unique Australian flora and fauna, attracted Astra to support this project in Australia. This project creates employment in a high value- added industry - the pharmaceutical area.
The Queensland State Government through the Department of Business, Industry and Regional Development constructed the $3 million Griffith Research Centre adjacent to Griffith University in order to facilitate private sector research and development. The building is leased back to Griffith University. In July 1993, the QPRI Astra Laboratories in the Griffith Research Centre were opened by the Hon. Jim Elder, Minister for Business, Industry and Regional Development.
Today, the QPRI has attracted top quality Australian scientists to conduct the research and development. The QPRI is now fully operational with state-of-the-art screening and structural elucidation equipment, including Queensland's only 600 MHz nuclear magnetic resonance spectrometer and computer aided drug design facilities, to allow natural products to be developed as new therapeutic agents.
Associate Professor Ronald J Quinn
Queensland Pharmaceutical Research Institute
Source: Department of the Environment and Water Resources.