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. The Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator (CARB-X) last week announced $467,000 in funding to GlyProVac to develop a maternal vaccine that targets Escherichia coli, the bacteria mainly responsible for neonatal sepsis, which is the leading cause of death among infants and a particular challenge in low- and middle-income countries. The funding will specifically support the development of the vaccine candidate GPV02, which offers protection to newborns through the antibodies passed on by vaccinated expectant mothers in utero and through breast milk after birth. GPV02 uses a unique approach compared to other attempted protein-based bacterial vaccines because it involves previously undiscovered natural sugar modifications and uses BEMAP technology to allow the vaccine to imitate E. coli, preparing the immune system to recognize the bacterium in the case of future infection.Last week, the Advisory Group on Immunization Practices at the US Centers for Disease Control and Prevention (CDC) recommended Valneva’s Ixchiq chikungunya vaccine for some travelers and laboratory researchers at risk of contracting the mosquito-borne virus. The United States records about 100 to 200 chikungunya cases a year in people infected abroad by the virus, which is mainly found in parts of Central and South America, Africa, and Asia. The vaccine was licensed by the Food and Drug Administration last fall for adults—the first vaccine approved for chikungunya. CDC has indicated that it may later expand the recommendation for people living in US territories where the virus may spread.A new extensive, long-term analysis from the Icahn School of Medicine at Mount Sinai found that COVID-19 vaccines induce long-lasting antibody responses, debunking previous claims that mRNA-based vaccine immunity wanes quickly. The researchers examined in over 8,000 samples collected over three years in New York City how antibody responses changed after infections, during the first series of vaccinations, during booster vaccinations, and during breakthrough infections. They concluded that the major reason for breakthrough infections is the virus evolving to evade immunity rather than waning immunity. The results will, hopefully, not only encourage people to continue to get vaccine boosters but also to continue research into new vaccines and viral variants.

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 Friday, the World Health Organization (WHO) announced the prequalification of a novel typhoid conjugate vaccine, developed through a global public-private partnership between SK bioscience and the International Vaccine Institute. Clinical trials in the Philippines and Nepal showed that the vaccine was safe to administer in infants and children as young at 6  months to two years and offered long-term protection with a single dose. As the rising global threats of climate change and antimicrobial resistance amplify the risk of typhoid, which causes between 120,000 and 160,000 deaths globally every year, this vaccine could help grow the global supply of typhoid conjugate vaccines and improve access in low- and middle-income countries through public procurement markets.Researchers have discovered a potent antibody, 95Mat5, that can neutralize a key type of neurotoxin produced by four deadly snake species in South Asia, Southeast Asia, and Africa. Currently, the standard treatment for snake bites, which kill an estimated 81,000 to 138,000 people globally every year and primarily occur in low- and middle-income countries, is antivenoms that consist of a variety of animal-harvested antibodies. These antivenoms can vary in efficacy and can also cause adverse immune reactions because the antibodies they use come from animals. Continued development of 95Mat5, which was synthetically created, could lead to a new antivenom that could be used to treat bites from the world's most dangerous venomous snakes and would be less likely to cause side effects because the antibody is human-derived.FHI 360 is leading a Phase 1 clinical trial of the biodegradable contraceptive implant Casea S, the first trial for a biodegradable contraceptive implant in more than 20 years. Casea S is implanted in the arm and works by releasing a synthetic hormone to prevent pregnancy for 18 to 24 months before dissolving. If proven successful in future trials, Casea S could serve as an alternative contraceptive option in the growing toolkit of products necessary to address the diverse needs and lifestyles of contraceptive users. Currently available implants are highly effective and safe and increasingly popular. Casea S could be an even better option, especially in low- and middle-income countries where users can face barriers to receiving care, because it dissolves by itself, eliminating the need for a removal procedure by a trained medical provider.  

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.

Over the course of the COVID-19 pandemic, more than 1 billion vaccine doses were delivered to the world’s poorest countries via the World Health Organization (WHO)-backed COVAX vaccine sharing scheme. While much attention has gone to evaluating the successes and shortcomings of this effort in the wake of the pandemic, far less has been directed towards the WHO program that helped facilitate the introduction of these vaccines and other technologies by certifying their safety and efficacy—a program that deserves equally nuanced examination.  For decades, the WHO prequalification (PQ) program has played an essential role in accelerating access to health products in low- and middle-income countries (LMICs) by reviewing their safety, efficacy, and quality. It is a stamp of approval that clears the way for multilateral agencies to procure drugs, vaccines, diagnostics, and vector control products, and it guides emerging regulatory agencies that might otherwise lack the capacity to conduct independent reviews. But despite the program’s critical role in the global health ecosystem, it has been plagued by both operational and procedural challenges that create unnecessary delays. External stakeholders highlight pain points in the PQ programThat paradox is on full display in an independent evaluation released last fall of the WHO Department of Regulation and Prequalification, which oversees the PQ program. The assessment lauds the PQ program’s successes in expanding global access to products, especially during the COVID-19 pandemic; however, it also highlights the need for increased communication and collaboration between the PQ department and key stakeholders in the public health ecosystem, including product developers, national regulatory authorities, procurers, and other WHO departments. It also notes how manufacturers who apply for PQ are especially keen to have more visibility into PQ decision timelines and roadmaps for the release of related technical standards and guidelines. Stakeholders also unanimously highlighted the limited resourcing at WHO headquarters as a key constraint across the PQ department. According to the evaluation, the department’s resources have remained stable between 2018 and 2022 (from 114 staff members in December 2019 to 115 in December 2022). However, the scope and the workload across all teams have increased substantially over the same period. This assessment echoes recommendations from a 2022 report from GHTC and the Duke Global Health Innovation Center, which also urged PQ to increase visibility into anticipated timelines for decision gates throughout the review process so developers can better anticipate communication and decision-making. The report also recommended that the PQ program be more transparent in publicly disclosing information on how it is performing against these targets, as well as provide access to regularly updated public databases with complete milestone information on all prequalified products. Moving towards greater efficiency and transparency Fortunately, recent moves by WHO suggest the agency is beginning to take this feedback seriously and pursue remedies. Alongside the release of the evaluation, WHO announced the forthcoming launch of a new electronic portal for processing PQ applications. The portal promises a one-stop shop for applicants to file applications and relevant documents, receive status notifications, and track and respond to requests—offering them a real-time picture of their application status. This portal should also drive major efficiency improvements, as applications are currently processed manually, meaning that WHO staff handled the more than 1,000 PQ applications received in 2022 without automated support mechanisms. For national regulatory agencies, particularly those involved in WHO’s Collaborative Registration Processes—which allow for regulators to rely on evaluations carried out by WHO and other participating stringent regulatory authorities to accelerate their regulatory decision-making—, the portal provides a single location where they can also access all relevant information and documents in tandem with WHO. Importantly, the portal will also capture process-related milestones in greater detail and integrate with the WHO website, which we hope will allow PQ to improve reporting and transparency. While, unfortunately, the intended January 2024 launch of the portal has been delayed to the second quarter of the year, the rollout of the portal should be a welcome step toward a more effective, efficient, and transparent PQ program. A new path forward for novel products?Alongside pursuing operational improvements to processing applications, it is also vital that WHO reevaluate the PQ process itself to ameliorate bottlenecks that delay access to critically needed new technologies. Our 2022 report identified the interplay between the PQ process and the release of WHO treatment and use guidelines as one such process area ripe for change. Currently, WHO PQ procedure states that before a product can complete the PQ process and be listed, the product must already be featured in published WHO policy guidelines that recommend its use in clinical practice or public health policy. Stakeholders with whom we spoke identified this sequence as an obstacle and a source of delay for the PQ of novel products since the committees that develop guidelines, which operate outside the PQ process, will not release them until the clinical data upon which the guidelines are based are formally published in peer-reviewed literature, which can often take some time. During the COVID-19 pandemic, WHO proved these functions could occur more flexibly and in parallel. For example, WHO released regularly updated “living guidelines” for COVID-19 therapeutics as new clinical evidence emerged and, in 2022, released interim guidance for novel shorter-course treatments for drug-resistant tuberculosis. WHO PQ also initiated and advanced PQ review of the COVID-19 antiviral known by the brand name Paxlovid before related guidance was released, ultimately announcing the PQ of the product on the same day as the living guidelines for COVID-19 therapeutics were updated to recommend its use. There is an opportunity for WHO to more broadly adopt lessons from this experience by both expanding the use of interim or living guidelines and redefining the process for prequalifying novel products so PQ and guidelines development can occur more in parallel. We hope PQ will pursue this opportunity with haste, as it could be a potential game changer and significantly reduce the timelines for product evaluation, helping products ultimately reach patients faster. We also urge member states to adopt policy changes and provide the PQ program with the resources it needs to meet its growing scope and demands. Despite some of its constraints, the PQ program remains a key cog in the global health ecosystem and an important driver of improved product access. There are indications that WHO and other key stakeholders have realized that changes must be made, as the current structures are weighing down the program's ability to quickly facilitate access to critical technologies, especially novel products. By implementing changes to make the application and review process more user-friendly and efficient and the procedure itself more streamlined, we believe the program can better deliver on its mission to make high-quality essential medical products available to all who urgently need them.