A first as GlaxoSmithKline files its malaria vaccine
This article was originally published in Scrip
GlaxoSmithKline has submitted its ground-breaking malaria vaccine RTS,S for approval in the EU, in the hope of using it in Africa, in line with plans announced last year.
The application will follow the Article 58 procedure, which allows the EMA to assess the quality, safety and efficacy of a product candidate manufactured in an EU member state for a disease recognized by the World Health Organization to be of major public health interest, and that is intended exclusively for use outside the EU.
Under this, an assessment will be made by the EMA in collaboration with the WHO to the same standards as those in place for marketing within the EU.
RTS,S is intended exclusively for use against the Plasmodium falciparum malaria parasite, which is most prevalent in sub-Saharan Africa, where around 90% of malaria deaths occur; 77% of these are in children aged under five years.
If the EMA grants a positive opinion, the WHO has indicated a policy recommendation may be possible by end of 2015. This is a formal review process by WHO designed to assist in the development of optimal immunization schedules for diseases that have a global public health impact.
It would also be the basis for MAAs to national regulatory authorities in countries in sub-Saharan Africa, which would hopefully help pave the way toward the large-scale implementation of the vaccine through African national immunisation programmes.
The filing is based on data from a Phase III study conducted in eight African countries that showed that the vaccine when given in three monthly doses can protect young children and infants from clinical malaria for up to 18 months after vaccination, although that protection faded from the 12 month follow-up point. After 18 months, RTS,S was shown to almost halve (a 46% reduction) the number of malaria cases in young children (aged five-17 months at first vaccination) and to reduce by around a quarter (a 27% reduction) the malaria cases in infants (aged six-12 weeks at first vaccination).
At the 12 month follow-up stage, there was a 56% reduction in clinical malaria cases and a 47% reduction in severe malaria for the five-17 month-old age group and 31% against clinical malaria and 37% against severe malaria in the six-12 week-old age group (scripintelligence.com, 12 November 2012).
While this level of protection falls well short of perfection, experts say it should still have a significant public health impact and are keen on the prospect of a new weapon against the disease, in addition to antimalarial drugs and bednets.
GSK says that the eventual price of RTS,S will cover the cost of manufacturing the vaccine together with a small return of around 5% that will be reinvested in R&D for second-generation malaria vaccines, or vaccines against other neglected tropical diseases.
RTS,S triggers an immune response against the P falciparum malaria parasite when it first enters the human host's bloodstream and/or when the parasite infects liver cells to prevent the parasite from infecting, maturing and multiplying in the liver, after which time the parasite would re-enter the bloodstream and infect red blood cells, leading to disease symptoms. It uses the proprietary AS01 adjuvant system containing QS-21 Stimulon, licensed from Antigenics (Agenus).