Breakthroughs Blog: Ebola

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. Experimental treatments for Ebola administered during the most recent outbreak in the Democratic Republic of Congo (DRC) appear to be working, according to preliminary data presented at the annual meeting of the American Society of Tropical Medicine and Hygiene. Four treatments are in use, including remdesivir, an antiviral drug; mAb114, a human antibody cloned from a survivor of an outbreak years ago in Zaire; REGN-EB3, a cocktail of cloned human antibodies; and ZMapp, a cocktail of antibodies made from a blend of human and mouse proteins. The death rate among patients in the DRC who received one or more of the experimental treatments was 43 percent—32 percent if the count excluded patients who were within hours of death when they arrived at the hospital. Experimental treatments for Ebola administered during the most recent outbreak in the Democratic Republic of Congo (DRC) appear to be working, according to preliminary data presented at the annual meeting of the American Society of Tropical Medicine and Hygiene. Four treatments are in use, including remdesivir, an antiviral drug; mAb114, a human antibody cloned from a survivor of an outbreak years ago in Zaire; REGN-EB3, a cocktail of cloned human antibodies; and ZMapp, a cocktail of antibodies made from a blend of human and mouse proteins. The death rate among patients in the DRC who received one or more of the experimental treatments was 43 percent—32 percent if the count excluded patients who were within hours of death when they arrived at the hospital. This compares to a death rate of 68 percent for Ebola patients in hospitals before the new treatments were approved for emergency use. A once-monthly injection proved as effective in suppressing HIV as daily pills in a second study by GlaxoSmithKline—potentially paving the way for a new treatment regimen that could be simpler for some people living with and seeking to suppress HIV. In the study, HIV-positive adults—who had not been on a long-established, daily three-drug oral regimen—were put on a 20-week, three-drug program of daily pills to suppress the virus before being switched to a monthly two-drug injection of cabotegravir and rilpivirine. After 48 weeks, the injection maintained a similar rate of suppression as the pills, supporting the results of an earlier study which involved adults who were on a daily, three-drug oral regimen to control the virus. The trial provides further evidence that a long-acting injection could offer an alternative to a daily, oral treatment regimen for people who previously achieved viral suppression. Dogs could offer a noninvasive way to detect malaria, according to a recent study presented at the annual meeting of the American Society of Tropical Medicine and Hygiene. In the study, a trio of dogs correctly “sniffed out” socks worn by malaria-infected children 70 percent of the time and those worn by non-infected children 90 percent of the time. The study focused on asymptomatic malaria carriers because of their key role in malaria’s persistence, since they act as hidden reservoirs of the disease. In the study, nylon socks were given to nearly 600 Gambian children to wear overnight and then frozen for 15 months while the dogs were trained to sniff out the disease, as previous research has shown that malaria alters the compounds that make up a person’s odor. While it may not be economically feasible to train and deploy dogs to all malaria-endemic countries, malaria-detection dogs could work at ports of entry in countries that have eliminated the disease and want to keep it out. This research also provides further evidence of the capabilities of dogs and their ability to help detect deadly diseases.

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 a new report, researchers at the Johns Hopkins Center for Health Security highlight 15 promising technologies that could help make the world better equipped to fight emerging infectious disease (EID) outbreaks and prevent such outbreaks from becoming catastrophic events. The list includes innovative solutions from vaccines that spread through populations like viruses to 3D printed drugs. The 15 technologies identified in the report fall under five broad categories—disease detection and surveillance, diagnostics, manufacture of pharmaceuticals, administration of vaccines and drugs, and medical care—and range in use from the early detection of an EID, to preventing its spread, and through to the care of patients. Notably, researchers looked for innovations that could be used in developing countries where EID outbreaks “hit first and hit hardest,” according to Dr. Crystal Watson, lead author of the report.  A novel synthetic DNA vaccine candidate against Ebola, which targets the virus’ surface, offered complete protection from the Zaire strain of the Ebola virus in preclinical research. Importantly, the vaccine candidate also demonstrated durability, showing strong immune responses one year after the last dose—a particularly challenging area for Ebola vaccines. Compared to traditional vaccine approaches that involve injection into muscle, synthetic non-viral–based DNA vaccines can be administered directly into the skin, resulting in consistent, potent, and rapid immunity. The antibody levels resulting from this vaccine candidate were equal to or higher than those for other vaccines currently being evaluated in the clinic at the Wistar Institute Vaccine & Immunotherapy Center, where the research was conducted. One researcher noted the success of an intradermal, low-dose regimen as encouraging in the pursuit to create safe and effective vaccines that are optimized for high-risk areas. A new type of malaria vaccine, known as a transmission-blocking vaccine (TBV), which aims to prevent mosquitoes from becoming infected by malaria parasites when feeding on infected humans, could one day become part of a suite of tools used to combat malaria. While traditionally scientists have focused on developing vaccines that prevent malaria infection from developing after a person is bitten with a parasite-carrying mosquito, a TBV works differently. A TBV signals the human body to begin making anti-malaria antibodies that will be passed to the mosquito when it bites the immunized person, disrupting the transmission cycle between mosquitoes and humans. While a TBV would not directly prevent an immunized person from getting infected, it would reduce the likelihood of people in that community becoming infected. A research team supported by the PATH Malaria Vaccine Initiative, the University of Buffalo and others have shown that the TBV approach could be effective. The researchers found that antibodies from a protein called Pfs25 effectively blocked the development of malaria-causing parasites in the gut of mosquitoes in animal studies.

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. Two new studies at Scripps Research have shown how human and mice antibodies can bind to and stop the infection of all five types of Ebolavirus—a key step in developing therapeutics capable of neutralizing all variants of the virus. During the studies, scientists observed the ability of a human antibody called ADI-15878 to bind directly to the viral “fusion loop,” which the virus uses to fuse with human cells to initiate infection, making it impossible for the virus to enter into human cells. Discovered in a human Ebola survivor, ADI-15878 is the only known antibody ever found to neutralize all five strains of the Ebola virus. A new study shows the potential of a novel microneedle platform to be used to administer vaccines during a pandemic. Researchers created a unique prototype vaccine that combined different technologies including: tiny microneedles that penetrate only the upper of the skin, a version of the H5N1 vaccine made from noninfectious “virus-like” particles that can be rapidly produced in tobacco plants, and an ingredient called an adjuvant that speeds up and strengthens the body’s response to the vaccine and has demonstrated protection against related viruses. While the study showed the product was effective in ferrets and appeared safe in humans, large-scale human trials are still needed. As vaccine researchers search for new approaches to combat pandemics, this prototype could lead to vaccine patches that could be distributed rapidly and administered without a nurse. Scientists plan to test the efficacy of a Zika vaccine candidate by intentionally infecting people with the virus, a strategy known as a human challenge trial. Researchers first launched the vaccine trial in March 2017 following an outbreak of the virus in the Americas in 2016 and had planned to open new trial sites in infection hot spots, but the effort is currently in limbo given the significant drop off in Zika cases. A major concern of researchers is that those participating in the trial may never be exposed to the virus, making it impossible to determine if the vaccine works. Plans to conduct a human challenge trial for this Zika vaccine candidate were halted by an ethics committee in 2017, which worried that people intentionally infected with the virus might transmit it to their sexual partners. Now, this method is being considered again as cases drop and industry loses interest in bringing a vaccine to market.

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. The Ministry of Public Health of the Democratic Republic of Congo has launched Ebola vaccinations for high-risk populations only one week after announcing the latest outbreak of the disease in the North Kivu province. Of the 44 cases reported so far, 17 have been confirmed. A total of 3,220 doses of the rVSV-ZEBOV vaccine candidate, developed by Merck, are currently available in country while additional doses have been requested. An agreement between Gavi, the Vaccine Alliance and Merck will ensure additional doses of the vaccine are available on an emergency basis as it goes through the licensing process. The World Health Organization has provided key logistical support in establishing a cold chain and sending necessary supplies for the vaccinations, aiding in the deployment of vaccine experts, and facilitating the negotiation of protocols with the manufacturer and the national authorities. Biobanks provide vital specimens and infrastructure to support scientific research and innovation. While in the developing world, biobanks are well established, issues such as unreliable internet connectivity, a lack of access to resources such as water and electricity, a lack of highly skilled and trained personnel, and the cost of setup have stifled their establishment in low- and middle-income countries (LMICs) on the African continent. Despite these barriers, LMICs in Africa should prioritize setting up biobanks, argues a group of researchers from the University of Western Cape and Stellenbosch University. They write, “Having access to rich genetic diversity across Africa would allow researchers to understand disease, develop better diagnostics and treatments, medicines and vaccines, geared toward the continent’s population.” A single-dose Zika vaccine candidate developed by researchers at The Ohio State University has proven effective in triggering an immune response in mice, according to a recent study. The vaccine uses a weakened, harmless form of the Vesicular stomatis virus—also known as foot-and-mouth diseases in cattle—to deliver proteins from the Zika virus. This method has been used with other vaccines, such as the Ebola vaccine being used in the recent outbreaks. While further testing is required to see if it is effective in humans, the vaccine candidate’s suggested ability to elicit an immune response with one dose means it has the potential to be especially valuable in hard-to-reach areas and low-resource settings.