Novel paediatric relapse-prevention treatment marks a major contribution towards malaria elimination efforts.
Medicines for Malaria Venture (MMV) today announces that the Australian Therapeutic Goods Administration (TGA) has approved the use of single-dose Kozenis (tafenoquine) in children aged 2 years and above in combination with chloroquine for the radical cure (prevention of relapse) of Plasmodium vivax (P. vivax) malaria.
The approval includes a novel, 50 mg dispersible tablet that can be dispersed in water and which was developed by GSK in partnership with MMV to facilitate use in children, who are disproportionately affected by the disease.
“We are proud to have worked with GSK to develop this child-friendly treatment and are thrilled by today’s announcement. P. vivax malaria is particularly dangerous for young children for whom repeated relapses can lead to cumulative severe anaemia and, in some cases, be fatal. Today, we have a tool to put a stop to the relentless relapse both for adults and children – we are one step closer to defeating this disease.” said Dr David Reddy, Chief Executive Officer, MMV.
Dr Thomas Breuer, Chief Global Health Officer, GSK, said: “We are delighted by this approval of Kozenis for paediatric populations. This achievement is testament to the dedication of GSK scientists and our partner MMV, who all worked tirelessly so the first relapse prevention treatment for P. vivax malaria in more than 60 years can be made available to the most vulnerable in society, our children.”
The submission was supported by a Phase 2b clinical study (TEACH) that evaluated dosages of tafenoquine based on weight for children between the age of 2 years, and weighing at least 10 kg, and up to 15 years.1
Kozenis is a single-dose treatment for the prevention of relapse of P. vivax and was approved for people aged 16 years and older by the TGA in 2018. It should be used with a course of chloroquine to treat the active blood stage infection, thereby achieving radical cure.
The current standard of care for prevention of P. vivax relapse requires a 7- or 14-day course of treatment with a drug called primaquine and at present there are no quality-assured, age-specific paediatric formulations marketed.
P. vivax malaria is estimated to cause between 4.1 and 5.1 million clinical infections every year, and poses a disproportionate burden for children aged 2 to 6 years who are four times as likely as adults to be infected.2,3 The clinical features of P. vivax malaria include fever, chills, vomiting, malaise, headache and muscle pain, and in some cases, can lead to severe malaria and death.4 P. vivax malaria infections also impact a child’s development and educational progress with evidence showing that children who experience repeated P. vivax infections are likely to suffer from physical and cognitive impairment.5,6,7
Further regulatory submissions are planned in malaria-endemic countries for paediatric indications for tafenoquine.
1. Vélez ID, Hien TT, Green JA, et al. Tafenoquine exposure assessment, safety, and relapse prevention efficacy in children with Plasmodium vivax malaria: an open-label, single-arm, non-comparative, multicentre, pharmacokinetic bridging, phase 2 trial. Lancet Child Adolesc Health 2021; published online Dec 3. https://doi.org/10.1016/S2352-4642(21)00328-X
2. World Health Organization. World Malaria Report 2021 (2021)
3. Howes, R.E et al. Am J Trop Med Hyg 2016; 95(6 Suppl): 15-34
4. Price RN et al. Vivax malaria: neglected and not benign. Am J Trop Med Hyg 2007; 77:79–87.
5. Fernando D et al. Cognitive performance at school entry of children living in malaria-endemic areas of Sri Lanka. Transactions of the Royal Society of Tropical Medicine and Hygiene. 97(2):161-5 (2003).
6. Vorasan N et al. Long-term impact of childhood malaria infection on school performance among school children in a malaria endemic area along the Thai-Myanmar border. Malaria Journal. 14:401 (2015).
7. Brasil LMBF et al. Cognitive performance of children living in endemic areas for Plasmodium vivax. Malaria Journal. 2017; 16: 370.