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innovation and technology

Fig. 2. Nano-carrier-drug-complexes for selective tumour-drug-delivery.

reaching the tumour and its metastases. At decades, various clinical chemotherapeutic
the same time, it causes non-specific toxicity drugs were integrated into a great variety of
to normal tissues and leads to adverse effects biocompatible nano-carriers to form drug-
including myelosuppression, neurotoxicity, loaded nanotherapeutics, and were tested
gastrointestinal disturbances, hair loss, both in vitro and in vivo. Currently, a number
and death. of the first generation nanotherapeutics (with
one drug species housed within one nano-
For chemotherapeutic drugs to exert maximal carrier structure as the common feature,
anticancer efficacy and low adverse effects, Figure 3), such as Abraxane®, Doxil®,
they have to be selectively delivered to Myocet®, Genexol-PM®, etc. have passed
the tumour without random dissemination clinical trials and entered into the market. As
in the body. Such an ideal scenario can these nanotherapeutics received approval for
potentially be achieved via the assistance clinical use, new generation nanotherapeutics
of nanotechnology. The use of active and are under development and are ready for
passive-targeted nanodrug-delivery systems clinical trials. However, only a handful of the
for selective tumour-drug-delivery is chiefly new generation nanotherapeutics managed
rooted in the key phenomenon of “enhanced to enter into clinical trials successfully, due
permeability and retention (EPR) effect”, that is, to the complexity in the development of
the hyperpermeation and prolonged retention policies on nanotoxicity/nanosafety, obtaining
of macromolecular-sized nano-carrier-drug- the necessary approval for clinical trial and
complexes within the tumour tissues due to the shortage of funding. In light of this,
the aberrant anatomical features found in a establishment of clear regulatory policies on
number of solid tumours, i.e. leaky vasculature nanotoxicity/nanosafety and clinical trials
with multiple blood capillary fenestrations at related to nanotherapeutics is necessary.
the diameter of 380-780 nm, coupled with the
lack of functional lymphatic drainage. In Malaysia, although the field of
nanotherapeutics research is still in its infancy,
This discovery of EPR in 1986 has helped numerous developmental efforts from local
to kick-start a rapid development of universities have been reported over the past 2
nano-carrier-assisted tumour delivery of decades. In the Faculty of Medicine, University
chemotherapeutic drugs. In the past three of Malaya, a small group of researchers

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