The Phase 3 trial of the most clinically advanced malaria vaccine candidate began May 26 with inoculations administered at the Bagamoyo Research and Training Centre of the Ifakara Health Institute (IHI) in Tanzania. In the coming months, the trial is expected to start in other countries across sub-Saharan Africa and will enroll up to 16,000 children and infants.
Developing a vaccine against malaria, a scientific challenge for decades, is critical to defeating the disease. A vaccine would complement existing interventions, such as bednets and effective drug therapies. Despite current control efforts, malaria still kills approximately 900,000 people every year, with most deaths occurring in Africa among children under the age of five. GlaxoSmithKline (GSK) Biologicals’ RTS,S is the first malaria vaccine to demonstrate promising safety and significant efficacy to warrant Phase 3 testing and is the leading candidate in the effort by the PATH Malaria Vaccine Initiative (MVI) to develop a malaria vaccine.
Recent Phase 2 studies showed that over an eight-month follow-up period, RTS,S reduced the risk of clinical episodes of malaria by 53 percent and has a promising safety and tolerability profile when used alongside standard infant vaccines. The Phase 3 trial builds on more than ten years of clinical research in Africa, including the first proof-of-concept study in children in 2004 and a proof-of-concept study in infants in 2007.
The culmination of more than twenty years of research by an innovative public-private partnership among MVI, GSK Biologicals, and their partners in Africa, the Phase 3 trial is an important milestone—but challenges remain. Scientists will continue to work in collaboration to ensure this vaccine, if proven effective, reaches those who need it most—the children of Africa.
As the trial extends to other sites, research centers across Africa will work with GSK Biologicals and MVI to further evaluate the efficacy and safety of the RTS,S vaccine. The full Phase 3 trial is designed to demonstrate how the vaccine performs in a large group of children and infants in different transmission settings across a wide geographic region.
"We are embarking on a scientific endeavor that could mean a new future for Africa," said Dr. Salim Abdulla, a principal investigator and director of IHI. "Building on the research our institute conducted for the Phase 2 trials, we are committed to advancing this vaccine, which could potentially save hundreds of thousands of lives."
The clinical development of RTS,S is being implemented by the Clinical Trial Partnership Committee (CTPC), a collaboration of leading African research institutes, Northern academic partners, MVI, and GSK Biologicals, with support from the Malaria Clinical Trials Alliance.
"This study will be the largest trial conducted in Africa of a vaccine specifically designed to help African children. We have great appreciation for the families and children participating," said Eusebio Macete, chair of the CTPC, and director of the Centro de Investigação em Saúde de Manhiça, Mozambique, another site that will engage in the Phase 3 trial. "Development of RTS,S in Africa has strengthened research capacity that will far outlast the trials."
The trial will evaluate the vaccine’s efficacy in two groups of children. One group, aged 6 to 12 weeks, will be vaccinated as part of their regular schedule of infant immunizations. The second group is children aged 5 to 17 months. The vaccine is intended for children under the age of five, who are the most vulnerable to malaria.
Phase 3 testing will occur in diverse transmission settings—ranging from areas where malaria occurs year-round to areas where it is more of a seasonal threat—to allow researchers to observe how the vaccine behaves in relation to intensity of malaria transmission. The various research centers were chosen for their track record of world-class clinical research, strong community relations, and commitment to meeting the highest international ethical and regulatory standards.
The study country has undertaken independent reviews to ensure the trial meets national safety, ethical, and legal standards for medical research. In addition, there is an independent data and safety monitoring board for the full trial, and a local safety monitor will govern each site. The trial has been designed in consultation with appropriate regulatory authorities in the European Union, the United States, and Africa and with the World Health Organization.
If the required regulatory clearances are granted and international and African national public health authorities recommend its use, RTS,S could be introduced in 2012 for children age 5 to 17 months. Following recommendations for use in infants, full availability is anticipated by 2014, potentially saving hundreds of thousands of lives. GSK and MVI are already working with malaria-affected countries and international institutions to ensure that a successful malaria vaccine will be readily available and affordable in the places and for those who need it most.
The Ifakara Health Institute (IHI), formerly Ifakara Health Research and Development Centre, is an autonomous, nonprofit, district-based, health research and resource institute headquartered in Ifakara, Tanzania. IHI was registered as a Tanzanian Trust in 1996 under the leadership of the Board of Trustees chaired by Ministry of Health and Social Welfare. IHI activities aim at generating new knowledge and relevant information for public health policy and action. The Bagamoyo branch of IHI was established in 2005 with the mission to promote effective solutions to important public health issues through clinical research, training, and service support for community development. The branch located in the premises of the Bagamoyo District Hospital also support clinical services and improvement of quality of care at the hospital and peripheral dispensaries in the district. For more information, please visit www.ihi.or.tz.
The PATH Malaria Vaccine Initiative (MVI) is a global program established at PATH through an initial grant from the Bill & Melinda Gates Foundation. MVI’s mission is to accelerate the development of malaria vaccines and ensure their availability and accessibility in the developing world. MVI’s vision is a world free from malaria. For more information, please visit www.malariavaccine.org.
PATH is an international nonprofit organization that creates sustainable, culturally relevant solutions, enabling communities worldwide to break longstanding cycles of poor health. By collaborating with diverse public- and private-sector partners, PATH helps provide appropriate health technologies and vital strategies that change the way people think and act. PATH’s work improves global health and well-being.
For more information, please visit www.path.org.
GlaxoSmithKline—one of the world’s leading research-based pharmaceutical and healthcare companies—is committed to improving the quality of human life by enabling people to do more, feel better, and live longer. For company information, please visit www.gsk.com/media.
GSK Biologicals, one of the world’s leading vaccine manufacturers, is headquartered in Rixensart, Belgium, where the majority of GlaxoSmithKline’s activities in the field of vaccine research, development, and production are conducted. In 2006, GSK Biologicals distributed more than 1.1 billion doses of vaccines to 169 countries. Of these doses, 75 percent of these went to the developing world. Approximately 136 million were doses of combination pediatric protect the world’s children from up to six diseases in one vaccine.
Posted May 28, 2009.