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North Bethesda, MD, United States

The new paradigm of elimination and eradication and constrained economic environment - combined with a first decade of experience - have lead the PATH Malaria Vaccine Initiative (MVI) to redefine its vaccine development strategy. This strategy has two targets: the pre-erythrocytic and sexual stages of the parasite, the latter including the parasite's evolution inside the mosquito. It encompasses four components: the selection of new antigens, identification of presenting platforms, adjuvant development and vaccine formulation and evaluation technologies. However, the development of a malaria vaccine cannot occur in isolation from other interventions; rather, it should be carried out in coordination with them. RTS,S is now in a Phase III trial, after demonstrating levels of efficacy from 30 to 50% against clinical malaria. Bringing a partially effective vaccine to licensure and use is a long and complex process that will require efficacy as well as public health impact data. Prime-boost and attenuated sporozoite approaches are, or will be, part of the portfolio required to build on these results, the former including use of adenovirus-based platforms. Current investments in blood-stage approaches are limited to attempting to resolve the challenge of AMA1 polymorphism and to an approach aimed at blocking re-entry of merozoites into red blood cells. MVI has prioritized the development of transmission-blocking vaccines and has identified some promising projects, while also researching their regulatory pathway. Two projects targeting Plasmodium vivax are supported. As part of its strategy, MVI has adopted a new classification of projects into small-scale preclinical feasibility studies, larger translational projects and, finally, vaccine candidates, the latter requiring proof-of-concept to be established in endemic countries. © 2010 Future Medicine Ltd. Source

Bingham A.,PATH Kenya | Gaspar F.,Traditional Medicine Institute | Lancaster K.,University of North Carolina at Chapel Hill | Conjera J.,M and e | And 2 more authors.
Malaria Journal | Year: 2012

Background: Malaria is a leading cause of mortality and morbidity in Mozambique, with nearly three-quarters of the country's malaria-related deaths occurring in children younger than five years. A malaria vaccine is not yet available, but planning is underway for a possible introduction, as soon as one becomes available. In an effort to inform the planning process, this study explored sociocultural and health communications issues among individuals at the community level who are both responsible for decisions about vaccine use and who are likely to influence decisions about vaccine use. Methods. Researchers conducted a qualitative study in two malaria-endemic districts in southern Mozambique. Using criterion-based sampling, they conducted 23 focus group discussions and 26 in-depth interviews. Implementation was guided by the engagement of community stakeholders. Results: Community members recognize that malaria contributes to high death rates and affects the workforce, school attendance, and the economy. Vaccines are seen as a means to reduce the threat of childhood illnesses and to keep children and the rest of the community healthy. Perceived constraints to accessing vaccine services include long queues, staff shortages, and a lack of resources at health care facilities. Local leaders play a significant role in motivating caregivers to have their children vaccinated. Participants generally felt that a vaccine could help to prevent malaria, although some voiced concern that the focus was only on young children and not on older children, pregnant women, and the elderly. Probed on their understanding of vaccine efficacy, participants voiced various views, including the perception that while some vaccines did not fully prevent disease they still had important benefits. Overall, it would be essential for local leaders to be involved in the design of specific messages for a future malaria vaccine communications strategy, and for those messages to be translated into local languages. Conclusions: Acceptance of routine childhood vaccines bodes well for a future malaria vaccine. Vaccinating children is a well-established routine that is viewed favourably in Mozambique. A communications strategy would need to build on existing immunization efforts and use trusted sources-including current government dissemination arrangements-to deliver health information. © 2012 Bingham et al.; licensee BioMed Central Ltd. Source

Brooks A.,Voltaire | Brooks A.,Swiss Tropical and Public Health Institute | Ba-Nguz A.,PATH Malaria Vaccine Initiative
Health Policy and Planning | Year: 2012

Traditionally it has taken years or decades for new public health interventions targeting diseases found in developing countries to be accessible to those most in need. One reason for the delay has been insufficient anticipation of the eventual processes and evidence required for decision making by countries. This paper describes research into the anticipated processes and data needed to inform decision making on malaria vaccines, the most advanced of which is still in phase 3 trials. From 2006 to 2008, a series of country consultations in Africa led to the development of a guide to assist countries in preparing their malaria vaccine decision-making frameworks. The guide builds upon the World Health Organization's Vaccine Introduction Guidelines. It identifies the processes and data for decisions, when they would be needed relative to the development timelines of the intervention, and where they will come from. Policy development will be supported by data (e.g. malaria disease burden; roles of other malaria interventions; malaria vaccine impact; economic and financial issues; malaria vaccine efficacy, quality and safety) as will implementation decisions (e.g. programmatic issues and socio-cultural environment). This generic guide can now be applied to any future malaria vaccine. The paper discusses the opportunities and challenges to early planning for country decision-making - from the potential for timely, evidence-informed decisions to the risks of over-promising around an intervention still under development. Careful and well-structured planning by countries is an important way to ensure that new interventions do not remain unused for years or decades after they become available. © World Health Organization 2012. All rights reserved. Source

Milstien J.,University of Maryland Baltimore County | Crdenas V.,PATH Malaria Vaccine Initiative | Cheyne J.,Voltaire | Brooks A.,Voltaire
Malaria Journal | Year: 2010

Abstract. Background. Recommendations from the World Health Organization (WHO) are crucial to inform developing country decisions to use, or not, a new intervention. This article analysed the WHO policy development process to predict its course for a malaria vaccine. Methods. The decision-making processes for one malaria intervention and four vaccines were classified through (1) consultations with staff and expert advisors to WHO's Global Malaria Programme (GMP) and Immunization, Vaccines and Biologicals Department (IVB); (2) analysis of the procedures and recommendations of the major policy-making bodies of these groups; (3) interviews with staff of partnerships working toward new vaccine availability; and (4) review and analyses of evidence informing key policy decisions. Case description. WHO policy formulation related to use of intermittent preventive treatment in infancy (IPTi) and the following vaccine interventions: Haemophilus influenzae type b conjugate vaccine (Hib), pneumococcal conjugate vaccine (PCV), rotavirus vaccine (RV), and human papillomavirus vaccine (HPV), five interventions which had relatively recently been through systematic WHO policy development processes as currently constituted, was analysed. Required information was categorized in three areas defined by a recent WHO publication on development of guidelines: safety and efficacy in relevant populations, implications for costs and population health, and localization of data to specific epidemiological situations. Discussion and evaluation. Data needs for a malaria vaccine include safety; the demonstration of efficacy in a range of epidemiological settings in the context of other malaria prevention interventions; and information on potential rebound in which disease increases subsequent to the intervention. In addition, a malaria vaccine would require attention to additional factors, such as costs and cost-effectiveness, supply and demand, impact of use on other interventions, and distribution issues. Conclusions. Although policy issues may be more complex for future vaccines, the lead-time between the date of product regulatory approval and a recommendation for its use in developing countries is decreasing. This study presents approaches to define in advance core data needs to support evidence-based decisions, to further decrease this lead-time, accelerating the availability of a malaria vaccine. Specific policy areas for which information should be collected are defined, including studying its use within the context of other malaria interventions. © 2010 Milstien et al; licensee BioMed Central Ltd. Source

Manganello J.A.,University at Albany | Carter T.C.,PATH Malaria Vaccine Initiative | Stokley S.,Centers for Disease Control and Prevention
Pediatrics | Year: 2011

OBJECTIVE: To identify and describe vaccine safety in US newspaper articles. METHODS: Articles (1147) from 44 states and Washington, DC, between January 1, 1995, and July 15, 2005, were identified by using the search terms "immunize or vaccine" and "adverse events or safety or exemption or danger or risk or damage or injury or side effect" and were coded by using a standardized data-collection instrument. RESULTS: The mean number of vaccine-safety articles per state was 26. Six (not mutually exclusive) topics were identified: vaccine-safety concerns (46%); vaccine policy (44%); vaccines are safe (20%); immunizations are required (10%); immunizations are not required (8%); and state/school exemption (8%). Three spikes in the number of newspaper articles about vaccine-safety issues were observed: in 1999 regarding rotavirus vaccine and in 2002 and 2003 regarding smallpox vaccine. Excluding articles that referred to rotavirus and smallpox vaccines, 37% of the articles had a negative take-home message. CONCLUSION: Ongoing monitoring of news on vaccine safety may help the content and framing of vaccine-safety messages. Copyright © 2011 by the American Academy of Pediatrics. Source

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