Hope for Africa in fight against RSV and new vaccine shows promise

Africa’s hope of further reducing the neonatal deaths estimated at 28 per 1,000 live births, has received a major boost after data from a new multinational, multicentre study now show increasing evidence of the possibility of protecting more infants against respiratory syncytial virus (RSV) through the immunization of their mothers with a vaccine before delivery.

Findings of a new study on maternal immunization have shown high prospects of preventing infant hospitalizations and deaths related to respiratory viruses and bacteria especially pneumonia that accounts for nearly 16% of all deaths of children below five years according to World Health Organization. (1)

In South Africa alone, an estimated 178,000 to 443,000 children under five years are likely to develop RSV lower respiratory tract infection (LRTI).

However, according to Professor Shabir Madhi of South Africa’s University of the Witwatersrand and lead author of the new study that was published on 30 July 2020 in the New England Journal of Medicine, the new data supports evidence that immunizing pregnant women with ResVax aluminum-adjuvanted RSV F vaccine could confer immunity to infants.

ResVax, which “the first RSV vaccine to show efficacy in a Phase 3 clinical trial”, has been developed by US-based Novavax but is yet to get approval from the U.S. Food and Drug Administration.

In the interim, Novavax says expectations are high after the study provided “first evidence that maternal vaccination could protect infants against RSV illness.” (2)

 “Of particular interest is an analysis of the data by sub-populations, which suggests that the vaccine better protects infants born to women from low- and middle-income countries (LMICs) such as South Africa,” says Prof Madhi who is also leading Africa’s first Covid-19 vaccine trial that is ongoing. (3)

Data from this study points to a high percentage of infants who are less likely to be hospitalized with RSV LRTI and severe low blood oxygen or hypoxemia.

During the study, a single dose of RSV was administered on 4636 pregnant women aged between 28 and 36 years, “to induce an antibody response by the immune system to the RSV F-Protein in the vaccine.”

The maternal antibodies, according to the study, are then “transferred naturally to the foetus during pregnancy and provides the first line of defence in protecting infants against RSV LRTI during the first 90 to 180 days of life.”

Up to 53% and 69% of infants born of women in the LMICs were less likely to be hospitalized for RSV LRTI and hypoxemia respectively according to these finding on RSV, a disease first discovered in the 1960s.

From the new data, there is potential of the RSV vaccine to bolster the capability of immunized pregnant women to “protect young infants under six months against severe RSV LRTI.”

Furthermore, the data shows “significant potential of an RSV vaccine for public health benefit in LMICs, which contribute more than 90% of all deaths from RSV and 50% of which occur outside health facilities.”

In South Africa the RSV research effort was carried out at the Madhi’s Vaccines and Infectious Diseases Analytics Research Unit, an affiliate of the South African Medical Research Council and other selected sites across this country of 57 million people 15.5 million of them children aged 0-14 years.

In the short term, countries, especially the LMICs, will have to wait a little longer before the vaccine is licensed for stocking and distribution for public use

Despite the delays in the approval of the drug by FDA and other agencies based on outcome of the study, effort nevertheless “paves the way for the development of this and/or other RSV vaccines for pregnant women to protect their infants against RSV during their first six months of life when they are most vulnerable to severe illness and death from RSV,” according to Madhi.

Meanwhile, Novavax, which has previously received US$89.1 million in financing from the Bill & Melinda Gates Foundation for the Prepare trial for ResVax, says it has commenced talks with “multiple potential commercial partners about the opportunity to bring ResVax to market globally.”

REFERENCES;

1.     https://www.afro.who.int/pt/node/523

2.     https://novavax.com/our-pipeline#rsv-f-vaccine

3.     https://www.wits.ac.za/news/latest-news/research-news/2020/2020-07/respiratory-syncytial-virus-rsv-vaccination-of-pregnant-women-could-prevent-pneumonia-in-babies.html

About the Author:

With great honor and pleasure, PharmaSources.com has now invited Shem Oirere as one of the writers. He graduated from the University of South Africa with a bachelor’s degree in International Relations and Diplomacy and also holds a Diploma in Journalism from the London School of Journalism. He previously worked for the Kenya Times, Nation Media Group and The People Daily over a twenty-year span as a business writer and Sub-editor. He wishes to share a view of the scenes behind Africa's latest pharma market trends with the rest of the world.