Breakthroughs Blog: Diagnostics

Authored by Elodie Jambert & Elizabeth Poll, Medicines for Malaria Venture, Switzerland; Panayota Bird, GSK; and Dr Marcus Lacerda, Fiocruz, Brazil  The Amazon is a renowned hotspot for biodiversity, but it’s also a hotspot for malaria. Brazil is one of the Latin American countries with the heaviest burden of malaria, with its Amazon region accounting for 99.5 percent of all national cases. Tackling malaria in Brazil is complicated by the fact that the vast majority of the burden is caused by the malaria parasite Plasmodium vivax. After causing an initial bout of malaria symptoms, this species of parasite has the ability to hide dormant in the liver of infected people, only to re-emerge and cause symptoms again several weeks to several months after initial infection. Another compounding issue is that the only medicine currently available to stop such relapse is primaquine–a medicine approved in the 1950s that must be taken for at least seven days. Given this lengthy course of treatment, many patients fail to complete the full course. It’s a challenge to explain to patients why they should take seven days of pills to treat something that appears to have resolved after the third day (the duration of treatment of the initial acute P. vivax malaria bout). As a result, the medicine often doesn’t work, and transmission of relapsing malaria is perpetuated. In Brazil, over the last 20 years, the burden of the more deadly Plasmodium falciparum has fallen from 50 to 10−15 percent. Yet, progress against P. vivax is yet to see the same success; this parasite now causes 89 percent of malaria cases. While P. vivax doesn’t kill as many people as P. falciparum, it is still debilitating, can also be lethal, and has substantial economic impact on families and nations. As such, it’s important to keep the attention of policymakers focused on malaria even in the face of other pressing public health issues, such as Zika and chikungunya viruses.A new solution for relapsing P. vivax in sightChildren in the village of Boa Vista, on the border of the Juma Reserve in the Brazilian Amazon. Photo: Neil Palmer/CIATFortunately, a new solution to tackle relapsing P. vivax malaria could be in sight. Medicines for Malaria Venture (MMV) and GSK have collaborated to develop a new, single-dose anti-relapse medicine, tafenoquine. The medicine was submitted for regulatory review to the US Food and Drug Administration and Australian Therapeutic Goods Administration at the end of 2017. If approved, it could be an important new treatment for individuals suffering from relapsing malaria, and could help to eliminate the disease in the Amazon.MMV and GSK have developed an access strategy together with in-country partners and are preparing the ground for the medicine’s potential launch in endemic countries. Country-level briefings are ongoing with the National Malaria Control Programmes (NMCP) in Brazil and six other endemic countries (Thailand, Ethiopia, Vietnam, Cambodia, Peru, and Colombia); their goal is to assess interest in introducing the new medicine into national practice and to understand what type of evidence NMCPs would need to support policy adoption. Developing diagnostics to make anti-relapse medicines safer for allPATH rapid diagnostic test to support treatment and elimination of P. vivax. Photo: PATHIntroduction of tafenoquine faces one additional challenge: As is the case with primaquine, people with a genetic deficiency in a specific enzyme known as glucose-6-phosphate dehydrogenase (G6PD) can suffer potentially serious side effects. On average, 8 percent of people in malaria-endemic countries are deficient in this enzyme. To reduce the risk of patients suffering this side effect, PATH is supporting development of a point-of-care diagnostic test to identify patients’ G6PD status and determine whether tafenoquine or primaquine can be safely administered. Concomitant use of this point-of-care diagnostic test will be critical for the correct and well-tolerated use of tafenoquine. Despite the World Health Organization’s recommendation that G6PD tests guide the use of primaquine, few endemic countries routinely use such testing today. In Brazil, the prevalence of G6PD deficiency varies depending on the immigration profile of the region. Most published papers on the subject estimate that the average prevalence among men in Brazil is around 5 percent, a statistic recently confirmed with preliminary data from a government-supported prevalence survey in endemic areas of the Brazilian Amazon.In light of this, additional data is being gathered. Initial preparations for an implementation study are underway in Brazil to demonstrate how a quantitative G6PD test would work in practice, prior to use of tafenoquine in the healthcare system. It is planned for the study to begin after regulatory approval of tafenoquine is granted. The team is also working with academics to model the cost effectiveness of the medicine paired with a G6PD test compared to current standard of care (primaquine without a test), as well as the potential impact of tafenoquine on malaria transmission and elimination. The Brazilian government will use these findings as it considers broader deployment of the intervention throughout malaria-endemic areas.Tafenoquine has potential for significant impact both for the individuals that suffer from this disease as well as for the regions focused on malaria elimination. We await the regulatory decisions on the medicine and will continue to work together as a team of partners to prepare the ground in the Brazilian Amazon to help make it malaria-free for all.

Interested in more global health innovation news? Every week GHTC scours media reports worldwide to deliver essential global health R&D news and content to your inbox. Sign-up now to receive our weekly R&D News Roundup email. In this regular feature on Breakthroughs, we highlight some of the most interesting reads in global health research from the past week. Researchers discovered that the meal times of malaria-infected organisms may impact the rate at which the malaria parasite multiplies in the host’s blood. A team at the University of Edinburgh studied the parasitic rhythms of reproduction and invasion of red blood cells in malaria-infected mice and found that the parasites timed their daily multiplication rhythms to match when the animals were fed. When the mice’s feeding time changed, the parasites altered the timing in which they invaded red blood cells. Researchers believe that interfering with the biological processes that link eating to these parasite rhythms—through diet, drugs, or other approaches—could reduce the spread of malaria infection A team of scientists recently created a prototype oral flu vaccine that does not need to be temperature controlled—paving the way for potential new oral vaccines that do not require refrigeration or freezing. Unlike traditional biological vaccines, which are made from part of a virus or bacteria and must be temperature controlled to remain stable, this oral vaccine prototype contains manmade peptides that mimic peptides in real viruses. Scientists found the prototype triggered a strong immune response when tested in human cell cultures and in mice. While more research is needed, these early results are promising. A heat-stable oral vaccine would be easier to transport and store, which could improve care in low-resource, hard-to-reach communities were immunization supply chains may be insufficient. Scientists at the Jena and Friedrich Schiller University Hospital are working to develop a rapid antibiotic resistance test. Current diagnostics for drug-resistant infections can take up to 72 hours to deliver results—a long amount of time for these infections, which can be acutely life-threatening. Using light-based analytical methods combined with microfluidic sample processes—which the researchers colloquially referred to as a miniature Lab-on-a-Chip system—the scientists were able to clearly identify bacterial strains and their resistances in fewer than three hours. New rapid tests for antibiotic-resistant infections could help get patients on treatment more quickly and reduce the overprescription of antibiotics.

Interested in more global health innovation news? Every week GHTC scours media reports worldwide to deliver essential global health R&D news and content to your inbox. Sign-up now to receive our weekly R&D News Roundup email. In this regular feature on Breakthroughs, we highlight some of the most interesting reads in global health research from the past week. A breath test could be an alternative approach to malaria diagnostics, according to a new study conducted by Washington University in St. Louis. The study focused on malaria-infected children in Malawi and showed that they had a different set of compounds in their breath compared to healthy children. Based on these compounds, researchers were then able to diagnose malaria infection with 83 percent accuracy. There is a critical need for alternative diagnostic methods for malaria, especially as the common, rapid diagnostic blood test is becoming less effective over time. More research is needed to study this diagnostic approach across different populations affected by malaria, but researchers are hopeful about this new avenue of malaria diagnostics. Researchers at the New York University College of Dentistry in collaboration with Rheonix Inc. have modified an existing model used for rapid HIV testing to test for the Zika virus. The newly developed test uses saliva for rapid identification of the diagnostic markers of the Zika virus and is an improvement over conventional Zika diagnostic techniques that require blood and can take hours to provide results. Further, this new test allows researchers to approximate the viral load in a saliva sample, allowing them to understand the severity of Zika and the body’s response to the virus, which is useful, especially among pregnant women. Researchers are optimistic about this test because it is quick and requires little training. Following a severe outbreak of yellow fever throughout Brazil, the country launched last month the world’s largest vaccine campaign using a fractional dose of the yellow fever vaccine. The goal of the campaign is to provide a fractional dose of the vaccine—one-fifth of the regular dose—to those living in 69 municipalities in the country, which will provide up to a year of protection against the illness. Though Brazil hopes to immunize 22.3 million individuals, only about 3.95 million have been vaccinated at this point. While this is not the first time fractional dosing of yellow fever vaccines have been used during an outbreak, this large-scale campaign will provide evidence and data for researchers aiming to implement similar campaigns to advance the goal of eliminating yellow fever epidemics globally by 2026.

There is no doubt that the past decade has brought transformative breakthroughs in global health innovation, from new medicines, to combatting leading child killers like malaria and tuberculosis (TB), to interventions that are making an AIDS-free generation possible. These game changers have saved millions of lives and helped unlock better health and opportunity for people around the world. The Global Health Technologies Coalition (GHTC) spent this past decade standing side-by-side in partnership with scientists and innovators, working to ensure they have the resources and supportive policies needed to advance innovation that truly drives impact. As we close out our tenth anniversary year and mark our first decade of advocacy, we wanted to take a moment to reflect on our shared progress and celebrate the headlines and moments that shaped global health research and development (R&D) over the past decade. Here are ten highlights: Could pills taken daily prevent HIV infection? That was a key question on researchers and activists minds in the early 2000s.By the end of the decade, the evidence pointed to yes. In 2012, the US Food and Drug Administration (FDA) approved the use of the antiretroviral drug Truvada as pre-exposure prophylaxis (PrEP) to prevent HIV infection. While it took several more years for PrEP to begin to be approved and introduced in low- and middle-income countries (LMICs), it has proved a powerful new tool in the global fight against HIV and AIDS. Revolutionary. Simple. Empowering. These are words that have been used to describe Sayana Press, an all-in-one injectable contraceptive developed by GHTC member PATH. Sayana Press combines a long-acting contraceptive with the easy-to-use Uniject injection system that involves minimal training, making it an especially suitable tool for low-resource settings and for women to self-administer. Since its introduction in 2014, more than 1 million doses of Sayana Press have been delivered to women worldwide, giving them greater power and autonomy over their reproductive health. Despite the fact that over 70 percent of all malaria deaths are children, before 2009 there was not a single high-quality malaria drug designed for kids. Instead, parents would crush adult tablets in what amounted to a daily struggle to provide an accurate dose as well as convince their kids to swallow these bitter tasting pills. This changed with the introduction of Coartem Dispersible, the first malaria medicine designed for children. Developed by GHTC member Medicines for Malaria Ventures, the medicine is affordable, easy-to-administer, sweet-tasting, and dosed for children. As of 2016, over 300 million treatments have been distributed worldwide, saving an estimated 750,000 lives. For more than a century, meningitis has ravaged a swath of the African continent known as the “meningitis belt,” killing one in ten people it sickened. But thanks to the efforts of a coalition of partners, including GHTC member PATH, we’ve stopped deadly meningitis A epidemics in their tracks. In 2010, MenAfriVac—a low-cost vaccine against mengingitis A—was introduced in Africa. Since then, more than 270 million people in 26 countries have been vaccinated, and thankfully, meningitis A is becoming a disease of the past. HIV and AIDS remains one of the greatest threats to women’s health globally, yet women and girls still lack the range of tools they need to protect themselves. Thanks to over a decade of effort by a unique partnership led by GHTC member the International Partnership for Microbicides, the future looks different. The partnership has advanced a new woman-center HIV prevention tool: a monthly, vaginal microbicide ring that deliver antiretroviral drugs. The groundbreaking new tool was found to reduce HIV risk in women in late-stage clinical trials in 2016, and it is now under regulatory review and poised for potential introduction worldwide. For parents with kids suffering from TB, getting their child to take multiple pills a day for months was a serious struggle, from trying to split up pills, to achieving the right dosage, to convincing children to swallow bitter tasting medicine. In 2016, this process became easier with the introduction of the first kid-friendly TB drugs. Developed by GHTC member TB Alliance, the drugs are appropriately dosed for children, dissolvable in water, and fruit-flavored to appeal to children. Already close to 80 countries, have adopted this improved treatment, with 700,000 courses ordered. Malaria has plagued humanity for tens of thousands of years. Fortunately, this past decade has brought a number of new and improved tools and approaches to tackle this age-old scourge, including the world’s first approved malaria vaccine, Mosquirix. In 2017, the World Health Organization announced plans to pilot the vaccine—developed by GHTC member PATH—in sub-Saharan Africa. While developing a high-efficacy vaccine against malaria has proved challenging due to the parasite’s complexity, Mosquirix, which reduced the rate of infection in children by 39 percent in clinical trials, is an important scientific breakthrough, and health officials hope it will prove a valuable addition in fighting malaria used alongside existing interventions. In 2014, the world’s deadliest Ebola outbreak caught the global community unaware and unprepared, devastating nations in Western Africa. While health workers went to work in the field to contain the immediate crisis, scientists went to work in their labs to develop a vaccine to prevent future epidemics. Thanks to research on Ebola vaccines that had been undertaken in the early 2000s, researchers were able to accelerate the leading Ebola vaccine candidate—RVSV-ZEBOV—from preclinical testing to phase III trials in less than two years. In 2016, it was announced that the vaccine was found nearly 100 percent effective in these trials. The vaccine could be approved by the FDA as early as 2019. More than two billion people worldwide suffer from hidden hunger—a condition characterized by deficiencies in micronutrients such as zinc, iron, and Vitamin A, which can cause stunted growth, blindness, and learning disabilities. In the 1990s, a young economist Howarth Bouis had a kernel of an idea: What if we could create better crops to provide better nutrition? His answer was biofortification, a process of naturally breeding sustenance crops so they are rich in micronutrients. After years of proof of concept research, in 2009, the nonprofit he founded—GHTC member HarvestPlus—introduced its first wave of crops in LMICs, providing nutrient-rich food for people in need. For decades, diagnosing multi-drug resistant TB (MDR-B) meant using older testing methods that took weeks to deliver results and required expensive laboratory equipment. In 2010, this began to change with the introduction of the Xpert MTB/RIF test, an automated diagnostic test developed by GHTC member FIND, which does not require microscopes or a laboratory, involves very little training to operate, and can deliver results in less than two hours, start to finish. FIND and partners will soon introduce a next-generation version—the Genexpert Omni—that is smaller, more portable, and battery-operated, which should further expand access to improved TB diagnosis. View a slideshow of more moments and milestones in global health R&D over the past decade. Here’s to ten more years of progress! At GHTC, we are proud to work with so many believers, innovators, and changemakers who are driving progress in global health. As we embark on 2018 and beyond, we recommit to continuing this momentum and look forward to another decade of advancing innovation to save lives.