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. Last week, Valneva and LimmaTech Biologics AG announced a new strategic partnership and exclusive licensing agreement for the development, manufacturing, and commercialization of Shigella4V, a tetravalent bioconjugate vaccine candidate against shigellosis. Shigellosis is caused by Shigella bacteria and is the second leading cause of fatal diarrheal disease globally, particularly in low- and middle-income countries. There are currently no approved vaccines for Shigella. Under the agreement, LimmaTech will receive support for conducting Phase 2 clinical trials of the vaccine candidate in low- and middle-income countries, which are expected to begin later this year. Then, Valneva will be responsible for the further development of the vaccine candidate through potential regulatory approval and commercialization if approved.The Biological Pest Control Centre in Valencia, Spain is releasing thousands of sterilized tiger mosquitoes, one of the species whose females transmit dengue to humans, to reduce the spread of dengue and other vector-borne diseases in Europe, as climate change has led to an expanding population of tiger mosquitoes across the continent and rising dengue rates globally. The lab employs an electron accelerator that uses radiation to sterilize the males, releasing an estimated 45,000 male mosquitos every week, who then unsuccessfully mate with the disease-spreading females, leading to an eventual reduction in the overall mosquito population. Similar sterilization techniques have been previously used to address disease vectors, but the Spanish lab is pioneering its use on the tiger mosquito.Last week, Indian company Biological E announced that the World Health Organization (WHO) has prequalified its novel oral poliovirus type 2 vaccine, a next-generation live attenuated oral vaccine, which can hopefully help reduce the incidence of vaccine-derived poliovirus, along with Indonesia PT Bio Farma's vaccine that was prequalified earlier this year. Cases of vaccine-derived poliovirus have increased in recent years in areas with low immunization rates. The new vaccine has improved genetic stability and carries a lower chance of starting new outbreaks of vaccine-derived virus compared to currently available poliovirus type 2 vaccines. Biological E said its manufacturing facilities can produce more than 500 million doses each year, with Indian regulators already having cleared the vaccine for export purposes.

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 results of a new study presented at the 2024 International AIDS Conference showed that long-acting injectable cabotegravir was safe and well tolerated as an HIV pre-exposure prophylaxis method in cisgender women before and during pregnancy. These exciting results come from an extension study of the efficacy trials among cisgender women that analyzed the outcomes of more than 300 pregnancies and infants. There has been limited data on the safety of long-acting injectable cabotegravir during pregnancy, so hopefully, these findings can fill that knowledge gap and lead to greater access to this highly effective HIV prevention option for this population, who may experience biological changes and social dynamics that can increase their likelihood of acquiring HIV during and after pregnancy.Last week, the Administration for Strategic Preparedness and Response at the US Department of Health and Human Services announced $25 million in funding to Walgreens to support a decentralized clinical trial testing COVID-19 vaccines. The study specifically aims to identify vaccine correlates of protection, or measurable immunity markers that correlate with protection against disease, using licensed or authorized COVID-19 vaccines to help assess immunity duration and streamline future clinical trials. This decentralized approach, which will include about 20 Walgreens pharmacies in urban, suburban, and rural communities, allows for a more diverse pool of study participants by bringing the study closer to where participants live. The funding comes through Project NextGen, a US government-led program to accelerate the development of next-generation COVID-19 technologies, including vaccines.  New data shows that Merck & Co.’s monoclonal antibody is safe and effective at reducing the incidence of respiratory syncytial virus (RSV)-related infections in infants. The Phase 2b/3 trial tested clesrovimab, also known as MK-1654, in healthy pre-term and full-term infants, finding that the antibody reduced the incidence of RSV-related infections over 150 days when compared to a placebo and hit key safety measures. The company announced that detailed findings will soon be presented to the scientific community and filed with global regulators. Hopefully, the antibody will eventually serve as an additional tool in the growing toolkit of new vaccines and monoclonal antibodies to address the burden of RSV in infants and older adults.

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. Last Wednesday, the World Health Organization (WHO) announced that it had prequalified an at-home, over-the-counter assay for hepatitis C virus (HCV), the first self-test to be prequalified for HCV, which causes an estimated 1 million new infections globally each year. The prequalification of the assay, manufactured by OraSure Technologies, extends the 2017 prequalification of the company’s HCV test for professional use. Self-testing is recommended to complement existing testing services based on evidence demonstrating that it increases access to and uptake of services. The prequalification status will hopefully enable procurement in low- and middle-income countries, expanding access to HCV testing and treatment services and helping to contribute to the global goal of HCV elimination.The Safety of Antimalarials in First Trimester consortium, made up of scientific and social research experts on malaria in pregnancy has kicked off preparation for the first-ever Phase 3b clinical trial testing the efficacy and safety of antimalarials in women in their first trimester of pregnancy, which will be cosponsored by Medicines for Malaria Venture and the Liverpool School of Tropical Medicine. Pregnant women are typically excluded from clinical trials out of fear of causing harm, leaving few medicines for malaria treatment and no medicines for prevention available for women in their first trimester despite the significant health risks associated with malaria in pregnancy. The data from this trial could enable pregnant women and all women of childbearing age to safely take these antimalarial medicines without risk of causing harm, as well as support the design of future trials targeting other infectious diseases affecting pregnant women in low- and middle-income countries.  New research has led to the discovery of a potent adjuvant, PVP-037, that could induce a greater, more durable, and broader immune response to vaccines. Adjuvants are compounds that enhance the immune response, which are key to vaccine development, particularly for inactivated virus vaccines. Researchers identified the compound by screening a library of more than 200,000 small molecules found in human immune cells. In mice, an optimized form of the adjuvant boosted antibodies against flu and SARS-CoV-2 when given alongside disease-causing antigens. The compound is stable, easy to work with, and can be formulated in most drug delivery systems, which would make it easier to integrate it into vaccine development. Further research will be needed to study how the adjuvant performs in the presence of actual pathogens, assess its impact on the durability of immune responses, and test whether it works across age groups.