WHO stamp of approval for drug combination in battle against malaria

Approved by the health regulator last week, Suprya® is the second seasonal malaria chemoprevention (SMC) drug to be ‘prequalified’ by WHO, a seal of recognition for the medications safety, quality and efficacy.

SMC refers to a strategy being promoted by WHO and its partners for preventive treatment of vulnerable groups such as children - even if they don't have the disease.

The drug is taken during the rainy season, when malaria transmission peaks and clinical trials have shown that use of SMC can reduce malaria incidence by 75 per cent.  The medicine comes as a child-friendly, sulfadoxine pyrimethamine and amodiaquine combination (SPAQ), that is taste-masked and dispersible.

Until now there was just one other WHO approved preventive formulation drug that children could take, produced by the Chinese-based Guilin Pharmaceuticals. The addition of a second, developed in partnership between the Geneva-based non-profit Medicines for Malaria Venture (MMV)  and the Indian pharmaceutical company  S Kant Healthcare, thus adds greatly to the security of the supply.

“Due to its effectiveness, use of seasonal preventive treatment has significantly expanded over recent years,” said MMV in a press release. “In 2015, 3.6 million children were protected and by 2020 that number increased to 33 million across 13 countries. However, throughout that period, there was only one WHO prequalified supplier, creating a vulnerability in product supply.”

André-Marie Tchouatieu, MMV lead helping to increase access to high quality antimalarial drugs said that in 2015 there were major shortages in the global supply of SPAQ. The current pandemic has further shone a light on the “fragility” of medical supply chains.

“Providing a second manufacturer of quality-assured, child-friendly SPAQ provides both increased supply and greater security of supply for this important protective medicine,” MMV added.

Malaria remains major cause of mortality

Malaria is a major cause of mortality in sub-Saharan Africa taking 400,000 lives and infecting 229 million people worldwide every year. While the death toll has dropped dramatically from the disease over the past decade, it remains one of the biggest killers of young children under the age of five in the region.

Due to the ever-changing epidemiology of the disease, as well as increased mosquito and parasite resistance to certain drug treatments and chemical vector control formulations, this means continuous adaptation of  prevention and treatment approaches is needed, targeting specific populations and locations.

It is therefore important that “research for SMC is supported to develop a suitable formulation that can overcome future resistance challenges,” urged Tchouatieu.

In 2012 the WHO recommended wider use of SMC therapies in sub-Saharan African countries, as an effective, affordable and safe prevention measure to reduce the malaria burden in young children.

When weighing up the benefits “a cost-effectiveness analysis conducted for SMC in seven countries indicates that the cost of severe malaria cases averted because children received the full doses of SMC ranged from 44 to 62 times the cost of SMC,” Tchouatieu noted.

SMC comes as a preventive approach, to complement the usual testing and treatment of suspected malaria cases.  In addition, the use of insecticide-treated bednets, and other integrated forms of vector management that target mosquito breeding grounds in water sources and around homes and communities, are other key forms of malaria management.

With a two-year shelf life, the Suprya® SMC is administered once a month over three consecutive days through the rainy season. In 2020 alone, 12 million treatments were delivered in the West African region.

This is not MMVs first rodeo in securing WHO prequalification for SMC drugs that can be used by children. In 2012, the organisation partnered with Guilin pharmaceuticals to develop and obtain the stamp of approval for the first child-friendly SPAQ, which was granted in 2014.

MMV are pushing the SMC programme by supporting efforts that go beyond the current targets which include,”extending the age group target beyond five years as well as extend the duration of SMC beyond the current four consecutive months,”  Tchouatieu said.

Ghana sees reduction in malaria deaths by 89 per cent - and gains maintained despite Covid

WHO’s Africa region continues to account for 94 per cent of all malaria cases worldwide - requiring significant effort from Ministries of Health, WHO and partners.

As one of the 11 countries with the highest burden of malaria, SMC has proven to be an effective tool in preventing disease in Ghana,  and has been implemented in the country since 2015. As Suprya® just received its prequalification Tchouatieu says it will soon be used in the country.

However, SMCs are only one of a number of interventions that have been used to successfully stop transmission and treat those infected.

“Beyond SMC, supporting research and scale up of other interventions against malaria such as next-generation chemoprevention and treatment medicines, vaccines, diagnostics, bed nets, IRS will also ensure that more children are protected against malaria morbidity and mortality,” said  Tchouatieu.

In a webinar as part of the activities marking this year’s World Malaria Day, Dr Keziah Malm, who heads Ghana’s National Malaria Control Programme (NMCP) said since 2012, millions of people have been targeted and reached with lifesaving tools such as SMC, long-lasting insecticide-treated nets (ITNs), Artemisinin-based combination therapy (ACTs) and indoor residual spraying (IRS).

“Malaria-related deaths across all ages in the country were reduced by 89 per cent from 2,799 in 2012 to 308 at the end of 2020.”

Only ten years ago eight people died from malaria in the country every day, but this has reduced to an average of one a day even amidst the Covid-19 pandemic. Still, malaria is treatable and preventable so there should be no reason for people to lose their lives to the disease.

However, it should be noted that sustaining the gains remain difficult due to the nature of the disease. Dr. Christian Lengeler of the Swiss Tropical and Public Health Institute told Geneva Solutions the parasites that cause malaria have created an incredibly stable biological system making them even harder to eliminate.

Malaria parasites are durable - and hard to eliminate from biological systems

“The parasites survive very well in humans for decades. In comparison with a viral infection like Covid after 10 days the immune system usually boots the virus out of the body, but with parasites that cause malaria, they're incredibly clever hiding in bodies over a long time.”

In terms of epidemics, malaria also seems to have a  much higher infection rate than other diseases. In terms of the “R” value which refers to the number of people who might be infected from one single human infection without preventive measures in place, Lengeler said “for Covid the R0 is between 2-3, for measles the number is about 12 and for malaria it is in the region of about 100.”

Malaria’s first vaccine

Pushing to disrupt the transmission, Ghana is one of the three countries piloting the RTS, S malaria vaccine. Developed by the British pharmaceutical company GlaxoSmithKline, in clinical trials the first ever malaria vaccine showed it reduces a child’s chance of contracting malaria by about 40 per cent.

If successful, the vaccine will be rolled out worldwide in the battle against plasmodium falciparum, the deadliest malaria parasite.

The dose has been in development for 30 years, yet results show partial protection against malaria, with experts attributing the efficacy to how complex the disease is. However, there are benefits of administering these injections, particularly when addressing the frequency of infection.

“Let's imagine that 100 children get three episodes of malaria every year. If this is reduced by a third as per the efficacy rate, you bring down the infection rate from three episodes to two episodes per child,” explained Lengeler.

It is by no means a perfect tool and researchers including Lengeler advocate that other measures are adopted, particularly those that interrupt transmission to tackle the disease.

The fight continues on many fronts, as a new vaccine candidate adds to hopes of preventing malaria in the most affected regions. So far, the R21 / Matrix-M product, developed by the University of Oxford, has delivered very promising results in its phase 2 clinical study. Published on the Lancet, the study conducted with 450 children in Burkina Faso, shows a vaccine efficacy of about 75 per cent.

Following the third phase due to roll out to 4,800 children in Burkina Faso, Mali, Kenya and Tanzania, the efficacy and safety will be reevaluated to be approved for 2023.

This in addition to other efforts including SMCs, which was shown to reduce “malaria deaths by at least 56 per cent” according to Tchouatieu, would definitely complement the current measures battling the disease.

“About 30 years ago I was working in a Tanzanian hospital. In the rainy season the paediatric ward would be full of children who are very sick from malaria and 10 per cent of them would die.  If I go today, in the same hospital during the rainy season I see empty beds. The number of severe cases of malaria has decreased spectacularly, and my vision of the future is going to the hospital seeing no malaria cases,” Lengeler concluded.