Breakthroughs Blog: Vaccines

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.Scientists from the Fraunhofer Society have developed a first-of-its kind technology that uses electron beams to produce inactivated vaccines quickly and reproducibly without the use of chemicals. Inactivated vaccines contain pathogens that have been killed so they are no longer harmful to patients. Often these pathogens are killed using chemicals, such as diluted formaldehyde. This process is time consuming and can have a negative impact on both the structure of the pathogen and the reproducibility of the vaccine. The new technique uses electrons to fragment the DNA of the pathogens while maintaining their external structure, which is key to triggering an effective immune response. It will likely be another two to four years before vaccines produced using electron beams can be tested in clinical trials. The US Food and Drug Administration (FDA) has granted Fast Track designation to Valneva’s chikungunya vaccine candidate, which will allow the product to receive expedited review by the agency given it holds potential to fill an unmet medical need. The company is expected to release phase 1 data for the vaccine candidate in the coming weeks. Currently, there are no approved treatments or vaccines for chikungunya‒a disease that causes debilitating joint pain‒though there are several candidate vaccines in clinical testing.The Marburg virus, a deadly cousin of Ebola, has been isolated in fruit bats in Sierra Leone, marking the first time the virus has been found in West Africa. According to two teams of scientists involved in this discovery, five bats caught in three health districts tested positive for the virus. Genetic testing revealed multiple strains of the virus in each bat, which suggests that the virus has circulated in West Africa for many years. This testing was done as part of a project funded by the US Agency for International Development, known as PREDICT, which aims to detect dangerous pathogens in animals and take steps to prevent them from crossing over into humans and triggering disease outbreaks. PREDICT takes a “one health” approach by uniting the work of medical doctors, veterinarians, and occasionally plant biologists to detect threats in other species.

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 government of the United Kingdom (UK), through a public-private partnership called UK Research and Innovation, is building the country’s first vaccine manufacturing and innovation center with additional funding and expertise from Janssen, Merck & Co., and Wellcome Trust. The center will focus on creating rapid, cost-effective ways to develop and manufacture vaccines for clinical trials and global distribution, with Ebola and Lassa fever among the infectious diseases the center will tackle. The vaccine manufacturing and innovation center will be based in Oxford and is slated to open in 2022. A comprehensive study in The Lancet Infectious Diseases shows the remarkable genetic diversity of HIV and reveals how the subtypes of the virus are distributed by country and region and where new strains are emerging. The systematic review and global survey found that the greatest diversity of HIV exists in Central Africa and subtype C causes the greatest number of HIV infections globally. Subtype C was also found to be the near-exclusive strain of HIV in southern Africa, where HIV prevalence is highest, strengthening the case for prioritizing the development of an HIV vaccine specific to this subtype. Overall, the study also highlighted the challenging nature of developing a vaccine against a virus that is so genetically diverse and widespread. Researchers from Loyola University Chicago Stritch School of Medicine have developed six antibodies that could be used to test for and potentially treat Zika—a virus which has afflicted more than 1.5 million people worldwide and for which there is no effective vaccine or treatment. Inexpensive to produce and identifiable via means like a simple filter paper test in the field, these antibodies have the potential to provide protection against the virus or could also be used in an antibody-based diagnostic test for Zika, potentially providing an inexpensive and quick means of monitoring for the virus. One researcher noted, “Rapid spread of the disease within the epidemic regions, coupled with migration of infected persons, has underscored the need for rapid, robust and inexpensive diagnostic tools and therapeutics.”

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 Population Council and its partners announced the launch of the first clinical trial to test the safety and efficacy of a male contraceptive gel—an innovation that could advance contraception and bring more equality to the burden of family planning, which is largely borne by women. The gel, known as NES/T, is a novel, reversible contraceptive composed of a progestin hormone used for female contraception and testosterone. The gel is designed to be applied daily and absorbed through the skin on the upper arms and shoulders. The phase 2b trial, sponsored by the National Institutes of Health, will test the product for pregnancy prevention among more than 400 couples. Should NES/T prove effective, it would be the first user-controlled method for contraception for men since the condom. Last Monday, South African drug maker Aspen Pharmacare launched a triple-antiretroviral (ARV) combination tablet for the treatment of HIV in South Africa—a country which accounts for 19 percent of the global burden of people living with HIV and 15 percent of new infections. The new medicine, known as Emdolten, is taken once daily and contains dolutegravir, an antiretroviral medication that counters the drug resistance that often develops with older HIV treatments, along with lamivudine and tenofovir disoproxil fumarate. In May, the South Africa Regulatory Authority and the European Medicines Agency issued a warning advising doctors not to prescribe dolutegravir to women seeking to becoming pregnant following cases of birth defects in a study; however, Aspen Pharmacare stated that using dolutegravir is safe for men, women not of child-bearing age, and child-bearing women using contraceptives, which account for approximately 70 percent of HIV patients. Researchers have developed a way to freeze-dry an inactivated poliovirus vaccine (IPV) so that it can be stored at elevated temperatures, up to 40°C, for four weeks and then dissolved for use without losing its potency—potentially offering a new tool to eradicate the disease. While existing oral vaccines have led to polio’s elimination in many countries, these oral vaccines contain a weakened live virus, which can cause paralysis in rare cases. Thus, there has been push to use IPVs, which contain dead strains of the virus. Although IPVs have already been introduced in many countries, their widespread use is inhibited by their sensitivity to temperatures above and below approximately 4°C (39.2°F).

Malaria has infected humans for a very long time and in more places than many realize. There’s evidence that 3,000 years ago, malaria killed King Tut. It stalked the marshlands and fens of Great Britain and was common in the American South until the middle of the 20th Century. Yet for this disease that has taken many turns over many millennia, the first 15 years of the 21st century are exceptional. During that time, deaths from malaria—which are primarily concentrated in young, African children—fell dramatically, from 839,000 in 2000 to 438,000 in 2015. But progress is not inevitable. Over the last two years, malaria deaths and infections have plateaued. In some areas they are rising, and not just in Africa. For example, amidst the deteriorating infrastructure of Venezuela, malaria infections have surged by 69 percent. Some of the problem involves a failure to invest the resources required to sustain the fight. But there are also other long-term challenges, including growing resistance among malaria-carrying mosquitoes to the insecticides used in bednets and indoor spraying campaigns—control measures that have been very effective at reducing infections. Malaria parasites are spreading in Southeast Asia that are resistant to the lifesaving malaria medicine artemisinin—and to other malaria drugs as well. There are reports along the Cambodian border of “triple mutant” malaria parasites that are resistant to artemisinin and two other once-reliable malaria drugs. The biggest fear is that these superbugs could spread into India and then into the malaria strongholds of Africa. Our goal at PATH’s Malaria Vaccine Initiative (MVI) is to help develop vaccines to aid in fighting malaria. If you look at the battle against infectious diseases that once spread death and misery, like smallpox, polio, measles, and whooping cough, vaccines helped turn the tide. Vaccines could do the same for malaria. However, malaria-causing parasites, like all parasites that cause disease, are biologically complex in ways that have made them notoriously hard to subdue with vaccines. But despite the challenge, and because of substantial investments made over the last couple of decades, we are closer than ever to a world where malaria vaccines can join the battle. The malaria vaccine closest to deployment is called RTS,S/AS01, and was developed by GSK. No vaccines are currently in use against human parasitic diseases, including against Plasmodium, the mosquito-transmitted parasite responsible for causing malaria. RTS,S will be the first, rolled out next year through a pilot introduction that will make it available to 750,000 young children living in areas of Ghana, Kenya, and Malawi, where malaria is common. This is the first step to possible wider use across Africa, where, alongside currently used interventions like bednets, indoor residual spraying, and drugs, it could help save thousands of lives. Yet, even as RTS,S is rolled out, which is a huge achievement, we continue to develop the next generation of malaria vaccines. MVI is working with partners on creative ways to optimize the use of RTS,S that could translate to increased public health impact against disease and death in young African children, and potentially support its use in community-wide campaigns to accelerate parasite elimination. A few years ago, we looked closer at what was originally seen as a fluke finding from more than a decade ago: that delaying and reducing the third dose of RTS,S might boost its protection against malaria. The small trial in 2014 provided intriguing evidence that this approach does indeed improve the quality of the immune response from RTS,S. A series of larger trials are now underway to explore whether different dosing approaches could positively impact efficacy. These studies are being further leveraged, in concert with advances in medicine that enable isolation and testing of individual antibodies with a strong affinity for targeting a disease. These monoclonal antibodies (mAbs) are driving exciting new therapies targeting certain cancers and autoimmune conditions. We are at the cutting-edge of efforts to perform proof-of-concept studies with mAbs to answer critical scientific questions and determine their applicability, as a potential supplemental tool, to preventing infection by malaria-causing parasites. We’re also excited about the potential to fight malaria with transmission-blocking vaccines (TBVs). A TBV could prevent mosquitoes that feed on malaria-infected humans from passing along their parasites to new victims. While not providing immediate protection from infection, high coverage with a TBV in a community where malaria is common would steadily reduce the risk of getting malaria from a mosquito bite—as the parasite’s survival is pegged to a continuous cycle, moving between humans and mosquito. A successful TBV could prevent malaria from returning to areas where it has been eliminated. Malaria has been plaguing humans for thousands of years and the parasites that cause the disease are constantly evolving to evade our attempts at control. But while the current fight may have plateaued, the lesson of the last decades is that a unified, well-funded assault on malaria—one committed to developing a variety of tools and making them widely available—can produce substantial progress. If we continue to invest in malaria vaccine development, and fund other promising work now underway to create a new generation of drugs, insecticides, diagnostics, and other tools, while strengthening the programs and systems that deliver them, we can turn the tide. And from there, we can confidently set our sights on eliminating and eradicating the disease forever.