The state of global malaria vaccine development
More candidates are moving through development
Progress toward developing malaria vaccines has accelerated in the last decade. Increased funding, greater awareness, and advances in science and in vaccine technologies have reinvigorated a field that had been constrained by the absence of a traditional market, few developers, and the technical complexity of developing any vaccine against a parasite.
Where we are
Today, the malaria vaccine development field is a dynamic arena of scientific endeavor. Increased funding and research is driving the discovery of new antigens and vaccine technologies, and many more malaria vaccine candidates are moving through the development pipeline.
In late 2012, the World Health Organization (WHO) published an update of the “Rainbow Tables,” which identified more than two dozen active malaria vaccine candidates in clinical development (human testing) and more than a dozen in preclinical development. In addition, GlaxoSmithKline Vaccines' RTS,S is currently in Phase 3 clinical development—making it the first malaria vaccine candidate to advance this far.
Challenges to developing malaria vaccines
Even with the recent progress, accelerating development of malaria vaccines remains as complex as ever. Developers face myriad challenges, including:
- There are no known correlates of immunity for malaria vaccines; therefore, vaccine candidates can only be shown to work (or not work) by going through clinical trials. The need for an empirical process makes developing malaria vaccines expensive and time consuming.
- Owing to the above, the field would benefit from the availability of diverse target antigens and antigen delivery platforms capable of inducing a variety of immune responses. Few new antigens have been added to the malaria vaccine candidate arsenal over the past decade, and immune-enhancing adjuvants, which are few in number and largely controlled by for-profit entities, are not freely available.
- The field needs additional, and more rigorously qualified, assays and models for assessing vaccine candidates to inform decision-making along the development pathway.
- Various business models are needed for ensuring the availability of vaccines once developed.
- Activities to ensure vaccine financing and use are crucial if a viable candidate is to advance through development and reach those in need.
A blueprint for developing malaria vaccines
The global malaria vaccine community has laid out a blueprint for moving forward, a pathway for developing highly efficacious malaria vaccines. As laid out in the Malaria Vaccine Technology Roadmap, an interim goal is to develop and license a first-generation vaccine by 2015 that has 50 percent protective efficacy against severe disease and death, with protection lasting at least one year without the need for boosting. Evidence suggests that the malaria vaccine community is on track, with RTS,S, to meet the 2015 mark.
- WHO's Tables of Malaria Vaccine Projects Globally: "The Rainbow Tables"
- Article: A Review of Malaria Vaccine Clinical Projects Based on the WHO Rainbow Table (308 KB PDF)
- Moran M, Guzman J, Ropars A, et al. The Malaria Product Pipeline: Planning for the Future. London, UK: The George Institute for International Health; 2007.
- Program for Appropriate Technology in Health (PATH), Staying the Course? Malaria Research and Development in a Time of Economic Uncertainty. Washington, DC: PATH; 2011.
- Program for Appropriate Technology in Health (PATH), Accelerating Progress Toward Malaria Vaccines. Bethesda, MD: PATH; 2007.
- Malkin E, Dubovsky F, Moree M. Progress Towards the Development of Malaria Vaccines. Trends in Parasitology. 2006;22(7):292–295.