What will a partly protective malaria vaccine mean to mothers in Africa?

Abstract

An effective vaccine would have tremendous benefit for the estimated 3 billion people living at risk of malaria. In today's Lancet, John Aponte and colleagues report that the candidate malaria vaccine RTS,S/AS02D is safe, immunogenic, and partly protective against infection in an infant population. 1 Aponte JJ Aide P Renom M et al. Safety of the RTS,S/AS02D candidate malaria vaccine in infants living in a highly endemic area of Mozambique: a double blind randomised controlled phase I/IIb trial. Lancet. 2007; 370: 1543-1551 Summary Full Text Full Text PDF PubMed Scopus (218) Google Scholar The primary endpoint was safety. Efficacy against infection, a secondary endpoint, was assessed during a 3-month follow-up after the last dose of vaccine. Aponte's report represents the next step in the systematic clinical evaluation of this recombinant protein vaccine with adjuvant, which started more than 15 years ago and has included studies in adults in the USA 2 Gordon DM McGovern TW Krzych U et al. Safety, immunogenicity, and efficacy of a recombinantly produced Plasmodium falciparum circumsporozoite protein-hepatitis B surface antigen subunit vaccine. J Infect Dis. 1995; 171: 1576-1585 Crossref PubMed Scopus (252) Google Scholar , 3 Stoute JA Slaoui M Heppner DG for the RTS,S Malaria Vaccine Evaluation GroupA preliminary evaluation of a recombinant circumsporozoite protein vaccine against Plasmodium falciparum malaria. N Engl J Med. 1997; 336: 86-91 Crossref PubMed Scopus (748) Google Scholar , 4 Kester KE McKinney DA Tornieporth N et al. Efficacy of recombinant circumsporozoite protein vaccine regimens against experimental Plasmodium falciparum malaria. J Infect Dis. 2001; 183: 640-647 Crossref PubMed Scopus (223) Google Scholar and in The Gambia, 5 Bojang KA Milligan PJ Pinder M et al. Efficacy of RTS,S/AS02A malaria vaccine against Plasmodium falciparum infection in semi-immune adult men in The Gambia: a randomised trial. Lancet. 2001; 358: 1927-1934 Summary Full Text Full Text PDF PubMed Scopus (442) Google Scholar in children aged 1–4 years in Mozambique, 6 Alonso PL Sacarlal J Aponte JJ et al. Efficacy of the RTS,S/AS02A vaccine against Plasmodium falciparum infection and disease in young African children: randomised controlled trial. Lancet. 2004; 364: 1411-1420 Summary Full Text Full Text PDF PubMed Scopus (631) Google Scholar , 7 Alonso PL Sacarlal J Aponte JJ et al. Duration of protection with RTS,S/AS02A malaria vaccine in prevention of Plasmodium falciparum disease in Mozambican children: single-blind extended follow-up of a randomised controlled trial. Lancet. 2005; 366: 2012-2018 Summary Full Text Full Text PDF PubMed Scopus (324) Google Scholar and now in infants in Mozambique. The teams that began working on this vaccine and its forerunners 8 Young JF Hockmeyer WT Gross M et al. Expression of Plasmodium falciparum circumsporozoite proteins in Escherichia coli for potential use in a human malaria vaccine. Science. 1985; 228: 958-962 Crossref PubMed Scopus (144) Google Scholar , 9 Ballou WR Hoffman SL Sherwood JA et al. Safety and efficacy of a recombinant DNA Plasmodium falciparum sporozoite vaccine. Lancet. 1987; 1: 1277-1281 Summary Full Text PDF PubMed Scopus (319) Google Scholar in the mid-1980s, and brought the vaccine to this point in development, deserve our praise and respect for their dedication, perseverance, and accomplishments. Safety of the RTS,S/AS02D candidate malaria vaccine in infants living in a highly endemic area of Mozambique: a double blind randomised controlled phase I/IIb trialThe RTS,S/AS02D malaria vaccine was safe, well tolerated, and immunogenic in young infants. These findings set the stage for expanded phase III efficacy studies to confirm vaccine efficacy against clinical malaria disease. Full-Text PDF Department of ErrorEpstein JE. What will a partly protective malaria vaccine mean to mothers in Africa? Lancet 2007; 370: 1523–24—In this Comment (Nov 3), the fourth sentence of the third paragraph should have read: “With the proportional analysis approach for the same data, the vaccine efficacy against acquiring an infection by 6 months of follow-up was 11%.” Full-Text PDF Department of ErrorEpstein JE. What will a partly protective malaria vaccine mean to mothers in Africa? Lancet 2007; 370: 1523–24—In this Comment (Nov 3), the fourth sentence of the third paragraph should have read: “With the proportional analysis approach for the same data, the vaccine efficacy against acquiring an infection by 6 months of follow-up was 11%.” Full-Text PDF