PRB

(January 2014) Some good news has finally arrived about the fight to eradicate malaria: A new vaccine may soon be available. British pharmaceutical GlaxoSmithKline (GSK) announced recently that its vaccine RTS,S protected young children and infants from malaria up to 18 months after vaccination in large-scale clinical trials. RTS,S was shown to almost halve the number of malaria cases in young children (ages 5 months to 17 months at first vaccination) and to reduce by around 25 percent the malaria cases in infants (ages 6 weeks to 12 weeks at first vaccination).¹

No Easy Answers

Malaria is still a huge problem, especially in Africa where the vaccine trials were conducted and where 80 percent of all cases occur. Globally in 2012, there were 207 million new cases among adults and children combined, and around 627,000 deaths, mostly to children. Although the bulk of cases occur in 14 African countries, malaria is found in 99 countries worldwide: Over 3 billion people, half of the global population, are at risk of acquiring the disease.²

The two major prevention methods are insecticide-treated nets (ITNs), generally draped around beds at night to ward off mosquitoes, and indoor residual spraying (IRS). These tools require $5 billion a year, but received only $2 billion in 2011.³ And drug resistance is persistent, making the quest for a vaccine even more pressing. Mosquito resistance to at least one insecticide used for malaria control has been identified in 64 countries.⁴

The UN’s Millennium Development Goal 6 aims to reverse the incidence of malaria and other major diseases by 2015.⁶ However, the World Malaria Report 2012 noted that funding for ITNs and IRS reached a plateau, leveling off between 2010 and 2012. The number of nets delivered to endemic countries in sub-Saharan Africa dropped from a peak of 145 million in 2010 to an estimated 66 million in 2012, and that means many households will not be able to replace existing nets when required, jeopardizing the progress that has been made.

Clinical Trials Require Resources

Inventing a malaria vaccine means breaking new medical ground. The current vaccine is the first-ever developed to protect against a parasite, said Duncan Learmouth, GSK’s senior vice president for developing countries and market access.⁶ GSK partnered with research centers in seven African countries and the PATH Malaria Vaccine Initiative (MVI), a nonprofit organization funded by the Bill & Melinda Gates Foundation, to test the vaccine. They vaccinated nearly 15,000 infants and children in Burkina Faso, Gabon, Ghana, Kenya, Malawi, Mozambique, and Tanzania.

Dr. Lucas Otieno of the Kenya Medical Research Institute-Walter Reed Project has been involved in the trials since 2005. In a recent interview in The Guardian, Otieno said that there had been no shortage of volunteers for the trial from families for whom malaria was a permanent fear. “In my site, we had 1,631 children and we recruited the initial 1,000 within about three months, which was very impressive,” he said.⁷

Vaccine Can Add to the Arsenal

According to the UN, countries with improved access to malaria control interventions have seen child mortality rates fall by about 20 percent.⁸ Millennium Development Goal 4 aims for a two-thirds decline in the mortality rate of children under 5 by 2015. Twelve African countries have shown rates in line with this goal, all of them malaria-endemic countries. Some experts attribute this progress to significant expansion of ITNs and artemisin-combination therapies, the most effective malaria treatment, along with improved sanitation.⁹

The vaccine could bolster these outcomes. “The sheer number of children affected by malaria means that the number of cases of the disease the vaccine can help prevent is impressive,” said Sir Andrew Witty, the chief executive officer of GSK.¹⁰

GSK and MVI have said they intend to submit an application to the European Medicines Agency next year for rollout of the vaccine. And if all goes well, the World Health Organization could follow as early as 2015 with a recommendation for large-scale implementation.

Heidi Worley is a senior writer/editor at the Population Reference Bureau.

References

1. “Africa: Malaria Vaccine Candidate Reduces Disease Over 18 Months of Follow-Up in Late-Stage Study,” All Africa.com, Oct. 7, 2013, accessed at http://allafrica.com/stories/201310080041.html,  on Oct. 11, 2013.
2. World Health Organization (WHO), World Malaria Report 2013 (Geneva: World Health Organization, 2013), accessed at www.who.int/malaria/publications/world_malaria_report_2013/report/en/index.html, on Dec. 12, 2013.
3. WHO, World Malaria Report 2012 (Geneva: World Health Organization, 2012), accessed at www.who.int/malaria/publications/world_malaria_report_2012/wmr2012_summary_en.pdf, on Oct. 23, 2013.
4. WHO, World Malaria Report 2012.
5. United Nations, “Goal 6: Combat HIV/AIDS, Malaria and Other Diseases,” UN Millennium Development Goals and Beyond 2015, accessed at www.un.org/millenniumgoals/aids.shtml, on Oct. 29, 2013.
6. Sarah Boseley, “Malaria Vaccine: Hope Rises for 2015 Target After Successful Trials,” The Guardian, Oct. 7, 2013, accessed at www.theguardian.com/society/2013/oct/08/malaria-vaccine-trial-children-babies, on Dec. 6, 2013.
7. Boseley, “Malaria Vaccine.”
8. United Nations, “Goal 6.”
9. Gabriel Demombynes and Ritva Reinikka, “Africa’s Success Story: Infant Morality Down, Africa Can End Poverty,” accessed at https://blogs.worldbank.org/africacan/africas-success-story-infant-mortality, on Oct. 23, 2013.
10. “Malaria Vaccine Candidate Reduces Disease Over 18 Months of Follow-up in Late-Stage Study of More Than 15,000 Infants and Young Children,” Glaxo Smith Kline press release, Oct. 8, 2013, accessed at www.gsk.com/media/press-releases/2011.html, on Dec. 6, 2013.