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. On Friday, the World Health Organization (WHO) announced the prequalification of Bavarian Nordic’s MVA-BN vaccine for mpox, the first-ever vaccine for the virus on the prequalification list. Prequalification status is anticipated to facilitate timely and increased access to the vaccine, helping to contain the current outbreak on the African continent by accelerating procurement by governments and international agencies and enabling national regulatory authorities to fast-track additional approvals. The vaccine has been licensed for use in people 18 years and older with a two-dose schedule given a month apart. However, the WHO Strategic Advisory Group of Experts has specifically recommended the use of the vaccine for people at a high risk of exposure in the context of an outbreak; thus, the vaccine has been used in infants, children, adolescents, and pregnant and immunocompromised people. It has also recommended single-dose use to stretch limited supplies while also urging the need to collect additional data about the vaccine’s safety and efficacy in these circumstances.Last week, Gilead published new results from the highly anticipated PURPOSE 2 trial, the second Phase 3 study of its twice-yearly, long-acting drug for HIV pre-exposure prophylaxis (PrEP), lenacapavir. The trial showed that the drug was able to reduce HIV infections by 96 percent compared with background HIV incidence and was 89 percent more effective than Gilead’s already available PrEP drug, Truvada. The study, which included more than 3,000 cisgender men, transgender men and women, and gender non-binary individuals aged 16 and older across seven countries, was unblinded early to offer lenacapavir to all patients in the study. This news follows the exciting results from the PURPOSE 1 trial of the drug in cisgender women and adolescent girls, which demonstrated 100 percent efficacy and was also unblinded early. Lenacapavir is currently available for use alongside other agents in patients with multidrug-resistant HIV, which make up only 2 percent of adults living with HIV, but, if approved for additional populations, the drug could be available as soon as 2025 and could be a game-changer for the HIV epidemic. Emergent BioSolutions last week announced that the Biomedical Advanced Research and Development Authority (BARDA) awarded the company a $41.9 million research and development option to its existing ten-year contract to further the development, validation, commercialization, and scale-up of the company’s monoclonal antibody treatment for Ebola virus infection. The treatment, Ebanga, was initially developed by Ridgeback Biotherapeutics with support from BARDA and was approved by the US Food and Drug Administration as a single infusion for the treatment of Ebola Zaire virus infection in 2022. The award is part of BARDA’s broader strategy to support treatments that can be deployed during virus outbreaks.

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. A team led by US Food and Drug Administration researchers last week published findings suggesting that three vaccines, already approved and stored in the Strategic National Stockpile, targeting earlier H5N1 clades that circulated in the early 2000s could provide some cross-neutralizing antibodies against the currently circulating 2.3.4.4b clade, which continues to infect dairy herds and some farm workers across the United States. Federal officials are already implementing a plan to produce 4.8 million doses of an updated vaccine targeting the current clade, with the first doses expected to be delivered this month, but, before being administered to people, the shots would still need to get regulatory approval. These new study results offer hope that the old vaccines could provide some protection if there is a need to start vaccinating humans before the updated vaccines become available.Recently published results from a Phase 2 clinical trial conducted in Sudan by the Drugs for Neglected Diseases initiative and the Institute of Endemic Diseases at the University of Khartoum found promising results for a new and improved treatment for people with post-kala-azar dermal leishmaniasis (PKDL), a serious condition that can develop after treatment for visceral leishmaniasis. The current treatment for PKDL is an injectable drug given for two to three months, which can cause life-threatening toxicity and must be administered under close supervision in a hospital. The new treatment is safer, shorter, cheaper, more effective, and more patient-friendly, only requiring patients to be admitted to the hospital for 14 days followed by an oral treatment that can be completed at home, offering hope of a new and improved tool for PDKL for affected populations, like in Sudan where nearly 20 percent of patients treated for visceral leishmaniasis will develop PKDL within six months post-treatment, the highest rate worldwide.The Sabin Vaccine Institute and the Makerere University Water Reed Project recently launched a Phase 2 clinical trial testing Sabin's vaccine against Sudan ebolavirus, which can cause deadly disease, as seen in the recent outbreak in Uganda that ended only last year. Although Sabin’s vaccine was one of three candidates chosen to be included in a trial during the outbreak, the outbreak ended before the trial could begin. The vaccine candidate, which is based on the same platform as Sabin’s Marburg vaccine candidate that is already undergoing its own Phase 2 trial, was found to be safe and elicit rapid, robust, and long-lasting immune responses in Phase 1 clinical and nonclinical studies. There is currently no approved vaccine for Sudan ebolavirus.

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. A new study that tested Gilead’s antiviral drug, obeldesivir, in primates given a lethal dose of the Ebola Sudan virus found that the drug may be effective in curing infections from the Sudan strain, for which there are currently no approved vaccines or treatments. The study tested a regimen of once-daily pills for ten days. If proven effective in humans and approved, it would be the first oral treatment for any subspecies of Ebola. Moreover, the drug can be stored at room temperature and is relatively inexpensive to manufacture, especially compared to the monoclonal antibodies approved for Ebola Zaire. Previous work in cell culture also showed that obeldesivir seems to work against all known species of Ebola and the related Marburg virus. Further research could confirm the drug's use as a pan-ebolavirus therapy; however, running clinical trials will prove challenging as there are long stretches between outbreaks of Ebola Sudan, in particular.A new initiative led by Imperial College London and co-funded by the Coalition for Epidemic Preparedness Innovations (CEPI) aims to develop next-generation coronavirus vaccines that not only reduce disease severity but also stop viral transmission, reducing the spread of disease. The project will deliberately infect healthy human volunteers with betacoronaviruses, including the virus that causes COVID-19, to test the efficacy of vaccines that are administered via nasal spray. Experts believe this method could be more effective in triggering the highly specialized mucosal immunity that can stop transmission by directly acting at the cells lining the nose, throat, and lungs—where the viruses enter the body. The human challenge trial design of the project is also unique. Imperial College London last year announced that the world’s first COVID-19 human challenge trial was safe, paving the way for broader use of this approach.A research team has discovered an enzyme in the species of sandfly that is primarily responsible for the spread of leishmaniasis in South America that they hope will lead to the development and commercialization of targeted traps to control the insect population and reduce the spread of the disease. Leishmaniasis can be disfiguring, and the severe form, visceral leishmnasis, which mostly occurs in Brazil, can be lethal if left untreated. The researchers analyzed the genome of the Lutzomyia longipalpis, a species of sandfly native to Brazil and South America, and identified the enzyme, Terpene Synthase, which is responsible for making the pheromone used to attract mates, a discovery that could be leveraged for future control technologies.

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. Last week, the Coalition for Epidemic Preparedness Innovations (CEPI) announced that it will give up to $14.9 million in funding for a new four-year project led by FIND to identify the most reliable tests to detect Lassa and Nipah virus infections, two zoonotic diseases that have, respectively, led to outbreaks in West Africa and South and Southeast Asia. The hope is the initiative will lead to the licensing and widespread availability of tests to help identify and contain future outbreaks early on, reducing cases and deaths of these serious diseases. This project will contribute to CEPI’s broader 100 Days Mission of rapidly developing tools against pandemic threats, as both diseases are among CEPI's priority pathogens.Researchers have developed a new synthetic antimicrobial compound, cresomycin, which can target many strains of antibiotic-resistant bacteria, including multidrug-resistant strains of Staphylococcus aureus and Escherichia coli. Many antibiotics work by binding to components of the bacteria that make proteins and disrupting them, but some bacteria have adapted resistance mechanisms to prevent this effect; cresomycin has improved binding ability. The researchers hope future studies will show that cresomycin and other compounds like it are safe for use in humans and effective against a variety of deadly resistant bacteria, paving the way for new solutions to stem the rising threat of antimicrobial resistance.A new study shows that Merck’s Ervebo Ebola vaccine was able to substantially lower the risk of people dying if they still developed the disease compared to those who were unvaccinated, even if they received the vaccine after they had already been infected. It is the first study to show that in addition to preventing infections, the vaccine can also save the lives of people who are already sick. The study, which looked at data from the 2018-2020 Ebola Zaire outbreak in the Democratic Republic of the Congo, found the fatality rate was halved among those vaccinated two or fewer days prior to illness compared to those who were unvaccinated. In addition to confirming the effectiveness of post-exposure use of Ervebo, the study also combated concerns that there might be interference between Ebola antibody treatments and the vaccine by showing that people who developed Ebola after being vaccinated were treated as effectively with antibody products as those who had not been vaccinated.