Safety and Efficacy of the RTS,S/AS01E Candidate Malaria
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View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Digital Library of the Tanzania Health Community Articles Safety and effi cacy of the RTS,S/AS01E candidate malaria vaccine given with expanded-programme-on-immunisation vaccines: 19 month follow-up of a randomised, open-label, phase 2 trial Kwaku Poku Asante, Salim Abdulla, Selidji Agnandji, John Lyimo, Johan Vekemans, Solange Soulanoudjingar, Ruth Owusu, Mwanajaa Shomari, Amanda Leach, Erik Jongert, Nahya Salim, Jose F Fernandes, David Dosoo, Maria Chikawe, Saadou Issifou, Kingsley Osei-Kwakye, Marc Lievens, Maria Paricek, Tina Möller, Stephen Apanga, Grace Mwangoka, Marie-Claude Dubois, Tigani Madi, Evans Kwara, Rose Minja, Aurore B Hounkpatin, Owusu Boahen, Kingsley Kayan, George Adjei, Daniel Chandramohan, Terrell Carter, Preeti Vansadia, Marla Sillman, Barbara Savarese, Christian Loucq, Didier Lapierre, Brian Greenwood, Joe Cohen, Peter Kremsner, Seth Owusu-Agyei, Marcel Tanner, Bertrand Lell Summary Background The RTS,S/AS01E candidate malaria vaccine is being developed for immunisation of infants in Africa Lancet Infect Dis 2011; through the expanded programme on immunisation (EPI). 8 month follow-up data have been reported for safety and 11: 741–49 Published Online immunogenicity of RTS,S/AS01E when integrated into the EPI. We report extended follow-up to 19 months, including effi cacy results. July 21, 2011 DOI:10.1016/S1473- 3099(11)70100-1 Methods We did a randomised, open-label, phase 2 trial of safety and effi cacy of the RTS,S/AS01E candidate malaria This online publication vaccine given with EPI vaccines between April 30, 2007, and Oct 7, 2009, in Ghana, Tanzania, and Gabon. Eligible has been corrected. children were 6–10 weeks of age at fi rst vaccination, without serious acute or chronic illness. All children received the The corrected version EPI diphtheria, tetanus, pertussis (inactivated whole-cell), and hepatitis-B vaccines, Haemophilus infl uenzae type b fi rst appeared at thelancet. com/infection on August 5, vaccine, and oral polio vaccine at study months 0, 1, and 2, and measles vaccine and yellow fever vaccines at study 2011 month 7. Participants were randomly assigned (1:1:1) to receive three doses of RTS,S/AS01E at 6, 10, and 14 weeks See Comment page 722 (0, 1, 2 month schedule) or at 6 weeks, 10 weeks, and 9 months (0, 2, 7 month schedule) or placebo. Randomisation was Kintampo Health Research according to a predefi ned block list with a computer-generated randomisation code. Detection of serious adverse events Centre, Kintampo, Ghana and malaria was by passive case detection. Antibodies against Plasmodium falciparum circumsporozoite protein and (K P Asante MD, R Owusu MD, HBsAg were monitored for 19 months. This study is registered with ClinicalTrials.gov, number NCT00436007. D Dosoo BSc, K Osei-Kwakye MD, S Apanga MD, E Kwara MD, O Boahen MPH, Findings 511 children were enrolled. Serious adverse events occurred in 57 participants in the RTS,S/AS01E K Kayan Dip Med Lab Tech, 0, 1, 2 month group (34%, 95% CI 27–41), 47 in the 0, 1, 7 month group (28%, 21–35), and 49 (29%, 22–36) in the G Adjei MSc, control group; none were judged to be related to study vaccination. At month 19, anticircumsporozoite immune S Owusu-Agyei PhD); London School of Hygiene and Tropical responses were signifi cantly higher in the RTS,S/AS01E groups than in the control group. Vaccine effi cacy for the Medicine, London, UK 0, 1, 2 month schedule (2 weeks after dose three to month 19, site-adjusted according-to-protocol analysis) was (K P Asante, D Chandramohan 53% (95% CI 26–70; p=0·0012) against fi rst malaria episodes and 59% (36–74; p=0·0001) against all malaria MD, B Greenwood, episodes. For the entire study period, (total vaccinated cohort) vaccine effi cacy against all malaria episodes was S Owusu-Agyei PhD); Ifakara Health Institute, Bagamoyo, higher with the 0, 1, 2 month schedule (57%, 95% CI 33–73; p=0·0002) than with the 0, 1, 7 month schedule Tanzania (S Abdulla MD, (32% CI 16–45; p=0·0003). 1 year after dose three, vaccine effi cacy against fi rst malaria episodes was similar for J Lyimo MD, M Shomari BSc, both schedules (0, 1, 2 month group, 61·6% [95% CI 35·6–77·1], p<0·001; 0, 1, 7 month group, 63·8% [40·4–78·0], N Salim MD, M Chikawe MD, p<0·001, according-to-protocol cohort). G Mwangoka MSc, R Minja CO, M Tanner PhD); Medical Research Unit, Albert Interpretation Vaccine effi cacy was consistent with the target put forward by the WHO-sponsored malaria vaccine Schweitzer Hospital, technology roadmap for a fi rst-generation malaria vaccine. The 0, 1, 2 month vaccine schedule has been selected for Lambaréné, Gabon phase 3 candidate vaccine assessment. (S Agnandji MD, S Soulanoudjingar MD, J F Fernandes MD, S Issifou MD, Funding Program for Appropriate Technology in Health Malaria Vaccine Initiative; GlaxoSmithKline Biologicals. M Paricek MD, T Möller MD candidate, T Madi MD, Introduction The RTS,S/AS candidate malaria vaccine is being A B Hounkpatin MD, P Kremsner FRCP, B Lell MD); The devastating morbidity and mortality that results from developed for immunisation of infants and children living Institute of Tropical Medicine, malaria in sub-Saharan Africa, especially in children less in malaria-endemic areas in sub-Saharan Africa as part of University of Tübingen, than 5 years of age, is well documented.1 The development the expanded programme on immunisation (EPI). The Tübingen, Germany of malaria vaccines has been identifi ed by national and vaccine has been assessed with two diff erent proprietary (S Agnandji, S Soulanoudjingar, J F Fernandes, S Issifou, international health authorities as a key component of a adjuvant systems, AS02 and AS01, both having shown a M Paricek, T Möller, T Madi, sustainable malaria control programme, which will have promising safety profi le in children5–9 and infants.10–12 The A B Hounkpatin, P Kremsner, large benefi ts for health and the economy.2–4 RTS,S antigen includes a carboxy-terminal segment of B Lell); GlaxoSmithKline www.thelancet.com/infection Vol 11 October 2011 741 Articles Biologicals, Rixensart, Belgium the Plasmodium falciparum circumsporozoite protein oral polio vaccine and BCG through national (J Vekemans MD, fused to the HBsAg. Simultaneously expressed in yeast immunisation programmes. Long lasting insecticide- A Leach MRCPCH, E Jongert PhD, M Lievens MSc, M-C Dubois MSc, cells together with free HBsAg, these antigens assemble impregnated bednets were distributed at screening. D Lapierre MD, J Cohen PhD); into particulate structures. The AS01E adjuvant system Written informed consent was obtained from each PATH Malaria Vaccine contains the immunostimulants MPL and QS21 and child’s parent(s) before study procedures were initiated. Initiative, Washington, DC, liposomes. Illiterate parents indicated consent with a thumbprint, USA (T Carter MHS, 12 P Vansadia MHS, M Sillman MHS, A phase 2 trial in Gabon, Ghana, and Tanzania in and a signature was obtained from a literate witness. B Savarese RN, C Loucq MD); and infants aged 6–10 weeks at fi rst vaccination was done to The trial was done in accordance with the Helsinki Swiss Tropical and Public assess safety, immunogenicity, and effi cacy of two Declaration of 1964 (revised in 1996)18 and according to Health Institute and University 19 RTS,S/AS01E schedules (0, 1, 2 month and 0, 1, 7 month Good Clinical Practice guidelines. Approval was of Basel, Basel, Switzerland (M Tanner) schedules) for potential integration into the EPI. Malaria obtained from the local and national ethics committees transmission is intense and perennial in these regions,9,13–15 relevant to each site, the London School of Hygiene and Correspondence to: Dr Kwaku Poku Asante, although the burden of malaria has recently decreased in Tropical Medicine Ethics Committee, UK, the Swiss Kintampo Health Research Lambaréné, Gabon.16,17 The primary analysis of safety and Tropical Institute Committee, Switzerland, and The Centre, Ghana Health Service, immunogenicity of the vaccine up to study-month 8 h as Western Institutional Review Board, USA. The design, PO Box 200, Kintampo, Brong 12 Ahafo Region, Ghana been reported. The incidence of serious adverse events conduct, and results of the trial were overseen by a kwakupoku.asante@ was balanced across groups and none were judged to be formally constituted independent data monitoring kintampo-hrc.org related to vaccination. Anticircumsporozoite and anti- committee. The study was done under US Food and HBsAg antibody responses were high in RTS,S/AS01E Drug Administration and national regulatory oversight recipients. At administration of RTS,S/AS01E with EPI as per existing regulations. The Ghana Food and Drugs antigens, seroprotection and seroconversion rates were Board, the National Institute for Medical Research of high, and predefi ned non-inferiority criteria were met for Tanzania, and the Ministry of Health in Gabon reviewed all EPI antigens with the exception of polio 3, although and approved the study before it started. when antibody concentrations measured at screening All children received diphtheria, tetanus, pertussis were taken into account, the rates of response to polio 3 (inactivated whole-cell), hepatitis B vaccine (Tritanrix, were comparable between groups.12 We assessed the GlaxoSmithKline Biologicals, Rixensart, Belgium), safety, immunogenicity, and effi cacy of RTS,S/AS01E over Haemophilus infl uenzae type b vaccine (Hiberix, 19 months, follow-up. GlaxoSmithKline Biologicals, Rixensart, Belgium), and oral polio vaccine (Polio Sabin, GlaxoSmithKline Methods Biologicals, Rixensart, Belgium) at study months 0, 1, Study design and participants and 2, and measles vaccine (Rouvax, Sanofi Pasteur, Lyon, Full study design and enrolment details have been France; some participants from Gabon received measles See Online for webappendix 1 published (webappendix 1).12 We did a randomised, open- vaccine sourced from the EPI [Serum Institute of India]), label, phase 2 trial.