 |
 |
Press Dossier, 7 April 2005, London |
| |
Combination therapy in global strategy for treatment of malaria |
| |
Every year, malaria kills 1-2 million people. 90% of deaths occur in sub-Saharan Africa. The disease is present in over 100 countries and threatens 40% of the world's population. Malaria remains the single largest cause of death for children under five in Africa. Malaria has a socio- economic impact: patients are often bedridden and incapable of carrying out normal daily activities.
Treatments exist but, in recent decades, drugs such as chloroquine or sulphadoxine-pyrimethamine have become increasingly ineffective due to drug resistance. Resistance to chloroquine now reaches over 90% in many parts of Africa. The spread of resistance is a serious threat to global public health (see map below).
Source: WHO
Scientists and doctors agree that the most effective treatment against malaria is a combination of drugs using artemisinin derivatives, highly potent extracts of the Chinese plant Artemesia annua. This Artemisinin-based combination therapy (ACT) is the quickest and most reliable way of clearing malaria infection, and is very well tolerated. Using a combination of drugs shortens the treatment course.
The World Health Organization (WHO) now actively encourages malaria-endemic countries to switch to ACT, and many of them are starting to do so. Overall, 40 countries in the world have included ACT in their malaria treatment protocols and a further 14 are considering doing so.
Why the need for fixed-dose combinations?
Compliance to treatment is essential to ensure treatment effectiveness and to prevent future resistance to ACT. But when combinations are provided as two separate drugs, patients might take only of one the two drugs or fail to complete the whole course. Taking one drug without the other increases the risk of resistance. Fixed-dose combinations (FDC's) combine two drugs into one tablet, instead of separate tablets, to ensure that the patients take both drugs in the right dose.
WHO recommends four therapeutic ACT options for malaria. These include:
- Artesunate - SP
- Artemether-lumefantrine
- Artesunate-amodiaquine
- Artesunate-mefloquine
So far are available only a co-blister artesunate/amodiaquine (ArsucamŪ) and a fixed-dose ACT artemether and lumefantrine (CoartemŪ). Although the latter is extremely effective, it needs to be taken with a fatty meal, can cause gastric side-effects, and is relatively expensive. New fixed-dose combinations are urgently needed to offer endemic countries, patients and doctors a wider range of treatment options adapted to their needs.
The Drugs for Neglected Diseases Initiative (DNDi) is a non for profit drug development initiative focused on developing new tools for neglected diseases. To address the gap in new effective malaria tools, DNDi set up a Fixed-dose Artesunate Combination Therapy or "FACT Project", in association with the UNICEF-UNDP-World Bank-WHO's Special Programme for Research and Training in Tropical Diseases (WHO/TDR). The "FACT" Malaria project brings together academics, public and private partners from around the world to develop FDC's for artesunate-amodiaquine and artesunate-mefloquine.
Independently, sanofi-aventis' Impact malaria initiates the development of the same combination.
DNDi and France's leading pharmaceutical company sanofi-aventis have teamed up to develop the artesunate-amodiaquine (AS/AQ) fixed dose combination which should be ready for registration in 2006. Treating infants and children for malaria is one of the key public health challenges. For this reason, AS/AQ will also be made available in special paediatric formulations to treat infants, children and teenagers.
To develop the artesunate-mefloquine FDC, DNDi is working with Far Manguinhos of Brazil.
Advantages of the new artesunate-amodiaquine fixed-dose combination
The use of a fixed-dose combination, in strengths adapted to the patients' ages, will allow a simple treatment of just three days, with a single daily administration of two tablets. The advantages are manifold:
- Rapid effect
- High cure rate (over 90%)
- Reduction of potential for transmission (less infective parasite in the blood)
- Ease of use (which increases compliance and therefore treatment effectiveness)
- Coverage of the whole population at risk (treatment can be used in both children and adults)
- Prevention of resistance and therefore further reduction of transmission
- Cheaper than buying combination of separate tablets or blister pack.
|
| |
| next >> |