Gillian Murphy, Ph.D.
Professor, Department of Oncology, University of Cambridge, UK
A novel strategy for targeting metalloproteinases in cancer
Epithelial tumours evolve in a multi-step manner, involving both inflammatory and mesenchymal cells. Although intrinsic factors drive malignant progression, the influence of the micro-environment of neoplastic cells is a major feature of tumorigenesis. Extracellular proteinases, notably the metalloproteinases, are key players in the regulation of this cellular environment, acting as major effectors of both cell-cell and cell-extracellular matrix (ECM) interactions. They are involved in modifying ECM integrity, growth factor availability and the function of cell surface signalling systems, with consequent effects on cellular differentiation, proliferation and apoptosis.This has made metalloproteinases important targets for therapeutic interventions in cancer and small molecule inhibitors focussed on chelation of the active site zinc and binding within the immediate active site pocket were developed. These were not successful in early clinical trials due to the relative lack of specificity and precise knowledge of the target proteinase(s) in specific cancers. We can now appreciate that it is essential that we understand the relative roles of the different enzymes (of which there are over 60) in terms of their pro and anti tumour activity and their precise sites of expression The next generations of metalloproteinase inhibitors need the added specificity that might be gained from an understanding of the structure of individual active sites and the role of extra catalytic domains in substrate binding and other aspects of their biology. We have prepared scFv antibodies to the extra catalytic domains of two membrane metalloproteinases, MMP-14 and ADAM17, that play key roles in the tumour microenvironment. Our rationale and experiences with these agents will be presented in more detail.
The global healthcare scene of which the pharmaceutical industry and its products are integral components is today at the cross roads. The high and unaffordable costs of drug research with estimates of over 1 billion dollars for every new drug discovered and developed, the very low success rates, the high degree of obsolescence due to undesirable adverse drug reactions, the decline in the development pipeline of new drugs, patent expiries leading to generic competition and the public’s disillusionment with use of chemicals for human consumption as drugs have all significantly contributed to the problems of this lifeline industry. The strategy adopted by the large R&D based Corporations to get bigger and bigger through mergers and acquisitions to improve cost-effectiveness and productivity of R&D has so far not worked effectively. Consequently, one of the recent trends in healthcare, articulated by many experts is to look for alternate or even complementary approaches to reduce the impact of rising costs of drugs on healthcare. Various new strategies for drug discovery such as the use of Natural Products especially medicinal plants are being actively pursued by healthcare planners and providers. Side by side, traditional systems of medicine whether from the oriental countries or the western nations are also having a serious relook to understand their usefulness in healthcare. To achieve its legitimate position in the healthcare scenario, it is essential to scientifically validate their claimed utility through appropriate and systematic research efforts including pre-clinical and clinical studies. In addition to their own use as medicines, knowledge on the Indian Traditional Medicines can be used as a platform for new drug discovery. The huge potential for carrying out systematic R&D programs for new Drug Discovery based on natural products and possible strategies to realise them in the coming decades will be explained in this presentation.
Ramani A. Aiyer, Ph.D., MBA
Principal, Shasta BioVentures, San Jose, CA, USA
New Drug R&D in India: Challenges & Opportunities
New drug discovery and development has become a global endeavor, with Western big pharmaceutical companies farming out more and more chemistry and biology research to Asia, particularly India and China. During the last decade, several Indian pharmaceutical companies have embarked on ambitious R&D programs, with slow but steady progress in developing new chemical / molecular entities. The Indian government has also made a strong commitment to promote innovation and entrepreneurship in the biotechnology sector. The first part of the talk will focus on a case study showing the entire process of discovery and development of a new drug recently launched for Rheumatoid Arthritis. We will then address the challenges of conducting innovative R&D in India and actions necessary to overcome them. The second part of the talk will make the case for developing Ayurvedic drug formulations for the Western / Global markets, again using the example of Rheumatoid Arthritis (Aamavaata). Ayurveda takes a holistic approach to disease diagnosis and therapy based on interactions among body type (prakriti), tri-doshas (three body humors), sapta-dhatus (seven tissues) and malas (excretions). The drugs prescribed are usually herbo-mineral formulations comprising multiple medicinal plants and / or metals. The manufacturing processes date back to Ayurvedic texts several thousand years old, and are compiled in the Ayurvedic Pharmacopeia. Also, the treatment modalities and drug formulations are “personalized” to fit different patient types, based on the holistic diagnoses mentioned earlier. There is a tremendous need to establish a sound basis for Ayurvedic drug discovery R&D for the modern world. We must find a scientific and ethical way to leverage the vast body of anecdotal and possibly retrospective data on patients undergoing Ayurvedic treatment. Combined with in vitro and in vivo biological data on Ayurvedic herbo-mineral formulations, the adoption of stringent manufacturing practices, and designing sound clinical trials to establish the safety and efficacy, India has a golden opportunity to expand the reach of Ayurvedic drugs into Western / Global medical practice.
