Study shows effective malaria drug combinations
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Researchers have identified two combinations of drugs to treat
malaria in Africa that could replace the widely used combination
of chloroquine and sulfadoxine-pyrimethamine (SP), which has
been rendered ineffective as the malaria parasite has grown re-
sistant to it.
The researchers, led by Philip J Rosenthal at the University of
California at San Francisco, published their findings in last
week's issue of The Lancet.
They gave 1,017 Ugandan children with malaria one of three drug
combinations, then monitored them for 28 days to see whether the
initial infection recurred or if the children got a new infec-
tion (by being bitten again by mosquitoes carrying the malaria
parasite).
When amodiaquine was used in combination with SP the risk of
treatment failing was higher than when it was combined with ar-
tesunate. However, when the former combination was used, the
risk of children getting a new infection was much lower.
The researchers argue that although treatment failure is usually
used as an indicator of how effective a treatment is, these two
opposing factors 'balance' each other out. As a result, they es-
timate that the need to re-treat patients was about the same for
both combinations.
They say, therefore, that either of combinations including amo-
diaquine would be preferable to the third combination tested
chloroquine and SP which they say has an n "unacceptably high"
risk of failing to treat the patient.
But Amir Attaran of the Institute of Population Health and Fac-
ulty of Law at the University of Ottawa, Canada, disagrees. In
an accompanying article in The Lancet, he calls the researchers'
argument to equate the two treatments "unpersuasive" and "quali-
tatively illogical".
"A treatment failure means that a sick patient gets sicker
possibly until he or she is dead," writes Attaran. "A new infec-
tion means that the patient returns to clinic for treatment
certainly a bother. Death and bother are highly different. They
never balance."
Attaran's comments may be too harsh, says Sanjeev Krishna at St
George's Hospital Medical School in London. He points out that
Attaran does not mention cost a crucial factor in drug choice
for developing countries. The treatment that reduces the risk of
a new infection is five times more expensive than the other.
Krishna told SciDev.Net that the question of whether it is worse
to have a recurrence of the same infection or a new infection is
"academic". Krishna believes that the researchers' conclusions
are "cautious, balanced and reasonably fair".
Attaran also points out that Uganda has now changed its malaria
policy to favour a different drug regime any of those under
study, one combining artemether with lumefantrine. Attaran says
this makes Rosenthal and colleagues' work out of date already.
This treatment has proved to be so effective, and is in such
high demand, that the World Health Organisation recently de-
clared that there could be a shortage of it until next year.
The short supply has pushed the drug's market value up three- to
five-fold, says Krishna.
A drug that works brilliantly but is expensive and in short sup-
ply is no good to the thousands of children currently dying of
malaria, Krishna points out. Until we have cheap and freely
available drug combinations that work, research such as Rosen-
thal's will always be needed, he adds.