Despite several modes of therapy such as chemotherapy, immunotherapy and radiotherapy, the treatment of cancer has still remained a challenge. Systemic chemotherapy is the main treatment available for disseminated malignant disease. Chemotherapy whether curative or palliative requires multiple cycles of treatment which unfortunately renders toxic side effects to the host cells. Several drug delivery systems were introduced namely liposomes, micropaticeles, supramolecular bio-vectors, polymeric conjugates and nano-particulates to facilitate effective chemotherapy with the anti-cancer agents. The introduction of Doxorubicin long circulating liposome in the market for cancer therapy has brought a renewed interest in the field of targeted drug delivery to cancer.

Out of several types of cancers, solid tumours are found to exhibit characteristics which can lead to their differentiation from normal tissues with respect to their microparticlate or vesicular uptake. Most significant character being enhanced permeability and retention (EPR) effect. The EPR effect renders tumor tissues to display several distinctive characters such as hyper vasculature, defective vascular architecture and a deficient lymphatic drainage which leads macromolecules and particulates to be accumulated preferentially and to be retained for a longer time in tumours.

Among several particulate delivery systems, solid lipid nanoparticles (SLN) have received great attention as drug carriers in the recent years. A striking advantage of the lipid nanoparticles is the feasibility of large scale production by high pressure homogenization technique. Majority of studies reported earlier focus the application of lipid nanoparticles for per-oral administration for the improvement of bio-availability of poorly water soluble drugs. However, today, there are many reports describing potentials of lipid nanoparticles for parenteral delivery particularly for the treatment of cancer.

- (The speaker is Co-ordinator, TIFAC Center of Relevance and Excellence in New Drug Delivery Systems was graduated in Pharmacy from Bangalore University. He obtained M.Pharm in Pharmaceutics from the University of Sagar, Sagar, M.P. and PhD from Delhi University. After working for a brief period in Govt. college of Pharmacy at Bangalore, he joined College of Pharmacy, Delhi and served there up till 1986. He joined M S University as professor in 1988 and then served as Head of the department from 1990 to 1998. At present Prof. Murthy is serving the university as senior professor and Co-ordinator of the" Center of relevance and excellence" in Drug Delivery Systems.)