Malaria vaccine shows promise

GlaxoSmithKline has designed the world’s first malaria vaccine, which could become available for certain populations as soon as October 2015. The shot, designated RTS, S, provides partial protection for up to four years and can be supported by a booster shot. While the efficacy of the vaccine wears off over time, researchers are optimistic that the vaccine could prevent millions of cases of the disease. According to Reuters, GlaxoSmithKline has been working on the vaccine for 30 years.¹ The results of the trial were recently published in the Lancet.

“Given that there were an estimated 198 million malaria cases in 2013, this level of efficacy potentially translates into millions of cases of malaria in children being prevented,” said Brian Greenwood, corresponding author and Professor of Clinical Tropical Medicine at London School of Hygiene & Tropical Medicine, in a press release.²

Findings

Designed with children in mind, researchers hoped that RTS, S would lead to the end of malaria, but early trial data revealed that the vaccine only reduced each child’s risk of contracting the disease. Overall, researchers found that the vaccine reduced rates of malaria with or without a booster shot.³ However, booster shots were found to enhance the efficacy of the vaccine. In babies, scientists were able to prevent a significant number of cases of malaria over the trial period.

Professor Greenwood explained, “Despite the falling efficacy over time, there is still a clear benefit from RTS,S/AS01. An average 1363 cases of clinical malaria were prevented over 4 years of follow-up for every 1000 children vaccinated, and 1774 cases in those who also received a booster shot. Over 3 years of follow-up, an average 558 cases were averted for every 1000 infants vaccinated, and 983 cases in those also given a booster dose.”² 

For the time being, researchers are waiting on approval from the European Medicines Agency and World Health Organization to begin using the vaccine in Africa. The Wall Street Journal notes that RTS, S is the most advanced defense against malaria in the world by at least a decade.⁴ 

“The European Medicines Agency (EMA) will assess the quality, safety, and efficacy of the vaccine based on these final data. If the EMA gives a favorable opinion, WHO could recommend the use of RTS,S/AS01 as early as October this year. If licensed, RTS,S/AS01 would be the first licensed human vaccine against a parasitic disease.”²

This advancement is a major development in the field of pharmacy technology. However, the drug alone does not provide a long-term solution for eradicating malaria. Currently, the WHO and other organizations rely on mosquito nets and other drugs for preventing the disease. These measures, when used in tandem with RTS, S, may be the best current solution, but will only be able to reduce cases of malaria. While GlaxoSmithKline and other companies will continue to work toward finding more robust vaccines, tackling malaria has proved historically difficult due to the complex nature of the disease.

¹ “World’s first malaria vaccine moves closer to use in Africa,” by Kate Kelland, Reuters, April 24, 2015. http://www.reuters.com/article/2015/04/24/us-health-malaria-vaccine-idUSKBN0NE2TY20150424

² “The Lancet: Scientists announce final trial results of the world’s most advanced malaria vaccine,” The Lancet, Public Release, April 23, 2015. http://www.eurekalert.org/pub_releases/2015-04/tl-tls042215.php

³ “Efficacy and safety of RTS,S/AS01 malaria vaccine with or without a booster dose in infants and children in Africa: final results of a phase 3, individually randomised, controlled trial,” The Lancet, April 23, 2015. http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)60721-8/abstract

⁴ “Problems Found With Glaxo’s Malaria Vaccine: Vaccine loses effectiveness over time but nevertheless provides benefit, scientists say,” by Denise Roland, The Wall Street Journal, April 24, 2015. http://www.wsj.com/articles/problems-found-with-glaxos-malaria-vaccine-1429867809