matrix or a bipartite network for computational approaches, which can affect the
prediction performance (Le and Nguyen-Ngoc 2018).
Integration of one or more repositioning approaches is required to meticulously
manoeuvre the heterogeneous amount of available data into an incorporated
workflow. More importantly, the new integration methods must be able to extend
its domain of applicability. Indeed, it is generally recognized that computational
techniques offer a more systematic repositioned plan and indubitably, a cost-
effective means to discover new interactions between drugs and diseases compared
to conventional approaches like in-lab experimental techniques. Nonetheless, in
scientific research, the outcomes from computational approaches will subsequently
always entail proper validation using experimental work to strengthen the findings.
5.5
New Horizons of DR
5.5.1
Neglected Conditions and Orphan Diseases
Indeed, DR has brought into spotlight the rare pathophysiological conditions/
diseases (e.g. orphan disease), which are often poorly characterized and receive
less attention from pharmaceutical companies to develop drug treatments. This is
because only a small grant or budget is allocated in mainly developing countries to
create new or repositioned drugs to combat the disease. According to the World
Health Organization (WHO), an orphan disease is defined as the prevalence of an
illness being less than 6.5–10 in 10,000 people (Aronson 2006). These types of
disorders have recently gained more attention and interest, since there are now
several orphan drugs available in the market such as haem arginate (for por-
phyria—acute intermittent, variegate, and hereditary), ibuprofen (for patent ductus
arteriosus in neonates), and N-acetylcysteine (for paracetamol poisoning) (Hift and
Meissner 2005).
Although there are approximately 8000 existing orphan diseases (Statista 2021),
increasing numbers of pharmaceutical industries are taking the initiative to formulate
repositioned drugs as compared to a decade ago, where there was only around 5% of
participation (Sardana et al. 2011). This is because of the latest development of
technologies (e.g. computational approaches) and the offered incentives and assis-
tance provided under the Orphan Drug Act (ODA) 1983. To encourage and ease the
burden of pharmaceutical and research organizations, the ODA 1983 has outlined
some benefits, including the following: (1) tax credits, (2) financial aids for research,
(3) fastening the marketing authorization process, and (4) marketing exclusivity
(Lavandeira 2002).
5.5.2
Personalized Medicine
Personalized medicine aims to improve the treatment course of some disorders by
utilizing genomic findings to integrate biomedical research and clinical medicine.
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