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INNOSC Theranostics and
Pharmacological Sciences Drug repositioning for NTDs treatment

Figure 1. Global prevalence of parasitic neglected tropical diseases, specifically Chagas disease, sleeping sickness, and leishmaniasis, as well as malaria,
based on the Global Burden of Disease Data (2019). Collectively, these conditions affect over 1.3 billion people worldwide. Data sourced from: Global
Health Data Exchange (https://ghdx.healthdata.org/).

impact of NTDs and a glaring lack of effective and accessible US$ 0.4 – 0.8 billion, compared to US$ 1 – 2 billion for
treatments, underscores an urgent need for innovative developing a new drug.
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health-care solutions and therapeutic strategies. However, The potential of drug repositioning is well-documented
the development of new drugs for NTDs faces considerable in various contexts. 11-13 For instance, thalidomide,
challenges. Primarily, the limited financial incentives for originally marketed as a sedative, found new purposes in
pharmaceutical companies are a major obstacle since these treating multiple myeloma and leprosy. The literature
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diseases predominantly affect poorer regions with minimal is rich with examples of successful drug repositioning,
market potential. In addition, the biological complexity of notably in oncology and cardiovascular diseases. 16-18
these parasitic diseases makes the development of specific Yet, paradoxically, this approach remains considerably
and effective treatments a formidable task. 6 underutilized in the realm of NTDs, despite its
2. The urgency of utilizing drug demonstrated potential in addressing parasitic diseases
A noteworthy example of the treatment
such as malaria.
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repositioning to combat NTDs of parasitic NTDs is the repositioning of miltefosine.
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Drug repositioning, also known as drug repurposing, Initially developed as an anticancer agent, miltefosine
involves reevaluating existing drugs for new therapeutic made a significant impact in 2002 when it was repurposed
uses. This approach offers a promising alternative to as the first oral antileishmanial medication. This milestone
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traditional drug discovery by reducing both the cost and in drug repositioning not only exemplifies the versatility of
time required to bring a treatment to market. Crucially, existing drugs but also highlights their potential to address
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since the safety profiles of these drugs are already established, challenging diseases beyond their original intended use.
the risk of adverse effects is significantly minimized. In the This example of repurposing has set a groundbreaking
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context of NTDs, drug repositioning may be more effective precedent, paving the way for more innovative and efficient
than de novo drug design, primarily due to its speed and therapeutic approaches in the fight against NTDs.
cost-effectiveness. Repurposing existing drugs circumvents Although Chagas disease, HAT, and leishmaniasis
the lengthy and costly process of developing new drugs present unique challenges, including complex life cycles of
from scratch, representing a crucial advantage when the causative parasites and diverse clinical manifestations,
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responding to urgent health needs in resource-limited drug repositioning offers a viable solution to swiftly address
settings, such as those typical of NTDs. Therefore, these these challenges by repurposing existing drugs with
advantages make drug repurposing a practical and efficient known antiparasitic properties. For instance, collectively,
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approach for addressing these diseases. For comparison, the studies by Porta et al., Charlton et al., and Sbaraglini
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drug repurposing typically shortens the development et al. present a comprehensive overview of over 100
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timeline to 3 – 12 years, as opposed to 12 – 18 years for approved drugs that have been repurposed and are in
new drug development (de novo). It also reduces costs to various stages of development as antiparasitic treatments
Volume 7 Issue 4 (2024) 2 doi: 10.36922/itps.3721