A randomized controlled trial of extended intermittent preventive antimalarial treatment in infants.
BACKGROUND
Intermittent preventive antimalarial treatment in infants (IPTi) with sulfadoxine-pyrimethamine reduces falciparum malaria and anemia but has not been evaluated in areas with intense perennial malaria transmission. It is unknown whether an additional treatment in the second year of life prolongs protection.


METHODS
A randomized, double-blinded, placebo-controlled trial with administration of sulfadoxine-pyrimethamine therapy at 3, 9, and 15 months of age was conducted with 1070 children in an area in Ghana where malaria is holoendemic. Participants were monitored for 21 months after recruitment through active follow-up visits and passive case detection. The primary end point was malaria incidence, and additional outcome measures were anemia, outpatient visits, hospital admissions, and mortality. Stratified analyses for 6-month periods after each treatment were performed.


RESULTS
Protective efficacy against malaria episodes was 20% (95% confidence interval [CI], 11%-29%). The frequency of malaria episodes was reduced after the first 2 sulfadoxine-pyrimethamine applications (protective efficacy, 23% [95% CI, 6%-36%] after the first dose and 17% [95% CI, 1%-30%] after the second dose). After the third treatment at month 15, however, no protection was achieved. Protection against the first or single anemia episode was only significant after the first IPTi dose (protective efficacy, 30%; 95% CI, 5%-49%). The number of anemia episodes increased after the last IPTi dose (protective efficacy, -24%; 95% CI, -50% to -2%).


CONCLUSIONS
In an area of intense perennial malaria transmission, sulfadoxine-pyrimethamine-based IPTi conferred considerably lower protection than reported in areas where the disease is moderately or seasonally endemic. Protective efficacy is age-dependent, and extension of IPTi into the second year of life does not provide any benefit.
Kobbe
Robin
R
Infectious Disease Epidemiology Group, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany.
Kreuzberg
Christina
C
Adjei
Samuel
S
Thompson
Benedicta
B
Langefeld
Iris
I
Thompson
Peter Apia
PA
Abruquah
Harry Hoffman
HH
Kreuels
Benno
B
Ayim
Matilda
M
Busch
Wibke
W
Marks
Florian
F
Amoah
Kwado
K
Opoku
Ernest
E
Meyer
Christian G
CG
Adjei
Ohene
O
May
Jürgen
J
D000818:Animals; D000962:Antimalarials / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D004338:Drug Combinations; D005260:Female; D005869:Ghana / Q000453:epidemiology; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000208:ethnology / Q000517:prevention & control*; D008297:Male; D010919:Placebos; D010963:Plasmodium falciparum; D015995:Prevalence; D011739:Pyrimethamine / Q000009:adverse effects / Q000627:therapeutic use*; D013413:Sulfadoxine / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
D000962:Antimalarials; D004338:Drug Combinations; D010919:Placebos; C001205:fanasil, pyrimethamine drug combination; D013413:Sulfadoxine; D011739:Pyrimethamine