South-East Asia Regional Conference on Epidemiology

<strong>South</strong>-<strong>East</strong> <strong>Asia</strong> <strong>Regional</strong> <strong>Conference</strong> on Epidemiology | 221
One of the challenges of the WHO protocol is that the follow-up of each patient has to be at
least for 28 days because partner drugs being assessed are long-acting drugs, and sometimes till 42
days or even 63 days depending on the drug to be tested, from the onset of the treatment. Results
from microscopy have to be double-checked for their accuracy since the measurement of the efficacy
is mainly based on asexual malaria parasites being present and accurately counted in blood before
and during treatment (7). The availability and use of quality drugs in the Mekong region is also
a big challenge. For example, there was a recent survey which found that a significant proportion
of antimalarial and other drugs being used in the region were either counterfeit or sub-standard,
triggering international multisectoral actions (8). It means that medicines under evaluation must be
of excellent quality matching the recognized international standards. The data generated have also to
be managed properly. There are different ways of computerising, analysing and reporting of results.
Researchers usually display their results in many different formats, sometimes rendering further
comparisons and conclusions difficult and complex to interpret. All research papers which are part
of programmatic activities should ideally go to peer review committees before being published. This
process is sometimes delaying the publication of research findings for years.
For the time being, a multi-country response to address falciparum resistance to ACTs is
being implemented on the Cambodia-Thailand border. In the past, with chloroquine and SP, there
was no or limited response to the unacceptably increasing failure rate of those drugs. Supporting
networks for monitoring resistance is fine but what about the response? WHO is facilitating
national and international experts to meet each other to reconcile contradicting opinions to discuss
what should be done, how to make it happen and how to influence policy-makers in the region and
globally (9,10). What is contributing to making a difference in building evidence is the systematic
use of the same agreed-upon methodology by researchers across countries and across continents.
This remains a big challenge since most of principal research investigators are not actually following
standardized research operational procedures, delaying further consolidation of evidence to convince
policy-makers on strategic orientation changes.
In the Mekong region, there are many sites which have been decided by principal investigators,
usually 3 to 4 per country, including China. These sites are supposed to implement the same protocol
everywhere. Antimalarial drugs tested are the recommended first-line drugs in the Mekong region,
which are either co-formulated artemisinin and dihydroartemisinin in China and Viet Nam, co-packaged
artemisinin and mefloquine promoted in Thailand and Cambodia, or co-formulated artemether and
lumefantrine in Lao PDR. Other efficacious combinations such as co-formulated artesunate and
pyronaridine are expected to be marketed and monitored from 2011 onwards.
The therapeutic failure rates (%) of all ACTs are available and the disappearance of clinical
symptoms and parasites are measured at regular intervals. The data are cross-checked to ensure their
quality in such a way that when presented to scientists and policy-makers by principal investigators,
they are not further challenged (11). From the evidence gathered on increasing therapeutic failure,
WHO is facilitating national decision-makers to shift to alternative drugs which, in their national
programme, are bound to be the best ones across the region. It is for the first time this year – 2010
- that all countries in the Mekong region are promoting the use of artemisinin-based combination
therapies which was not the case before. It is one of the results of international community, the Global
Fund, and also WHO and its partners’ efforts to make sure that all countries promote quality ACTs
through public and private sector providers.
Artemisinin combinations that are based on artemisinin discovered in China are impacting on the
parasites from the merozoites to the schizonts. These are very powerful since these target all the 48hour
cycle of parasites maturation in red cells, whereas quinine only attacks the last 24-hour cycle. It
has some importance when we look at the efficacy of artemisinins. One of the most interesting data