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Introduction. Artemisinin-based combinations (ACT) are the current frontline curative therapy for uncomplicated malaria in Burkina Faso. Sulfadoxine-pyrimethamine (SP) is used for the preventive treatment of pregnant women (IPTp) while SP plus amodiaquine (SP-AQ) is recommended for children under five in seasonal malaria chemoprevention (SMC). This study aimed to assess the proportions of mutations in the Pfdhfr, Pfdhps, and Pfmdr1 genes from isolates collected during household surveys in Burkina Faso. Methods. Dried blood spots from Plasmodium falciparum-positive cases at three sites (Orodara, Gaoua, and Banfora) collected during the peak of transmission were analyzed for mutations in Pfcrt (codons 72-76, 93, 97, 145, 218, 343, 350 and 353), Pfmdr-1 (codons 86, 184, 1034, 1042 and 1246) dhfr (codons 51, 59, 108, 164) and dhps (at codons 431, 436, 437, 540, 581, 613) genes using deep sequencing of multiplexed PCR amplicons. Results. Of the 377 samples analyzed, 346 (91.7%), 369 (97.9%), 368 (97.6%), and 374 (99.2%) were successfully sequenced for Pfcrt, Pfmdr-1, dhfr, and dhps, respectively. Most of the samples had a Pfcrt wild-type allele (89.3%). The 76T mutation was below 10%. The most frequent Pfmdr-1 mutation was detected at codon 184 (Y>F, 30.9%). The single mutant genotype (NFSND) predominated (66.7%), followed by the wild-type genotype (NYSND, 30.4%). The highest dhfr mutations were observed at codon 59R (69.8%), followed by codons 51I (66.6%) and 108N (14.7%). The double mutant genotype (ACIRSI) predominated (52.4%). For mutation in the dhps gene, the highest frequency was observed at codon 437K (89.3%), followed by codons 436A (61.2%), and 613S (14.4%). The double mutant genotype (IAKKAA) and the single mutant genotype (ISKKAA) were predominant (37.7 % and 37.2 %, respectively). The most frequent dhfr/dhps haplotypes were the triple mutant ACIRSI/IAKKAA (23%), the wild-type ACNCSI/ISKKAA (19%) and the double mutant ACIRSI/ISKKAA (14%). A septuple mutant ACIRNI/VAKKGA was observed in 2 isolates from Gaoua (0.5%). Conclusion. The efficacy of ACT partner drugs and drugs used in IPTp and SMC does not appear to be affected by the low proportion of highly resistant mutants observed in this study. Continued monitoring, including molecular surveillance, is critical for decision-making on effective treatment policy in Burkina Faso.

Bioassay-guided fractionation of the organic extract obtained from stem barks of the African plant Lophira lanceolata has led to the isolation of seven biflavonoids, including the new α′-chlorolophirone E (5) and 5′-chlorolophirone D (6). Among the isolated compounds, the bichalcone lophirone E was identified as a potent gametocytocidal agent with an IC50 value in the nanomolar range and negligible cytotoxicity (selectivity index = 570). Lophirone E proved to be about 100 times more active against P. falciparum stage V gametocytes than on asexual blood stages, thus exhibiting a unique stage-specific activity profile. The isolation of structural analogues allowed to draw preliminary structure-activity relationships, identifying the critical positions on the chemical scaffold of lophirone E.