Widespread HPV vaccination protects unvaccinated women
HPV vaccination has herd effects, protecting unvaccinated individuals due to decreased virus prevalence. A surveillance study of 1,600 women aged 13–26 years from Cincinnati investigated the changed epidemiology of vaccine strains of HPV in the 11 years since the introduction of the 4-valent vaccine in 2006.1
The researchers detected HPV in 7% of vaccinated subjects in 2017 compared to 35% in the pre-vaccination era. Importantly, a 40% decrease was also observed in unvaccinated individuals.
The study found evidence for cross-protection of the 4-valent vaccine against additional five genetically related strains of HPV. However, herd immunity was not detected for these strains.
1. Spinner C, Ding L, Bernstein DI, Brown DR, Franco EL, Covert C, Kahn JA. Human Papillomavirus Vaccine Effectiveness and Herd Protection in Young Women. Pediatrics. 2019. doi:10.1542/peds.2018–1902.
Alzheimer’s disease vaccine had promising phase-2 results
The anti-amyloid vaccine UB-311 (United Neuroscience) was safe in a double-blind placebo-controlled Phase 2 trial involving 42 patients with early-stage Alzheimer’s and mild cognitive impairment. 96% of subjects in the experimental arm responded and maintained anti-Aβ antibodies. They showed improved brain function and reduced levels of toxic plaques.
UB-311 is a synthetic vaccine containing the N-terminus of Aβ peptides coupled to a helper T-cell epitope. It is designed to stimulate Th2 response and avoid autoimmune reactions.
Dengue vaccine candidate efficacious in a phase 3 trial
The dengue vaccine candidate TAK-003 (Takeda) proved effective in preventing dengue fever in a placebo-controlled Phase 3 study enrolling >20,000 children 4–16 years of age from eight endemic countries in Latin America and Asia. The interim results compared efficacy of two different dosage levels at the 15-month point. The actual rates were not disclosed.
TAK-003 is a tetravalent recombinant live attenuated vaccine with a genetic backbone derived from a serotype 2 virus. It is administered regardless of whether the subjects had prior infection.
Influenza vaccine for the elderly and a universal influenza vaccine prepare for phase 3 studies
The 4-valent recombinant nanoparticle influenza vaccine NanoFlu (Novavax) elicited higher antibody responses against several H3N2 strains than the leading vaccine for the elderly, Fluzone High-Dose (Sanofi). The Phase 2 study tested NanoFlu with or without the Matrix-M adjuvant in 1,400 people aged ≥65 years and determined optimal formulation with the adjuvant for a Phase 3 trial.
The universal influenza vaccine candidate Flu-V (hVIVO) ameliorated the course of mild-to-moderate influenza disease in a placebo-controlled Phase 2b challenge trial. Flu-V is a synthetic polypeptide targeting directing both T- and B-cell responses to internal proteins of wide range of strains. As a universal vaccine, researchers hope that it might obviate the need for annual re-vaccination, minimize the risk of antigenic mismatch and help control pandemic strains as well.
Celiac disease vaccine fast-tracked by FDA
The celiac disease vaccine Nexvax2 (ImmusanT) has received fast-track designation by the US Food and Drug Administration (FDA), which should ensure an expedited review for the vaccine, now in a Phase 2 trial. Celiac patients develop autoimmune reaction and gut inflammation upon digesting gluten. The vaccine, which contains gluten peptides, is designed to sensitize individuals with the HLA-DQ2.5 immune recognition allele (>90% of all celiac patients). There is no approved treatment other than complete avoidance of gluten-containing foods.
Influenza vaccine effectiveness might exceed 70% this season according to a mid-term estimate
The seasonal influenza vaccine has prevented 72% of cases in Canada, a January report estimates.1 The effectiveness was 20% at this time last year. According to the study, this season has been dominated by the H1N1 strains of influenza A, which contrasts with last season’s predominance of the H3N2 strains that mutate more quickly and therefore increased mismatch with the vaccine strains.
1. Skowronski DM, Leir S, Sabaiduc S, Murti M, Dickinson JA, Olsha R, Gubbay JB, Croxen MA, Charest H, Chan T, Bastien N, Li Y, Krajden M, De Serres G. Interim estimates of 2018/19 vaccine effectiveness against influenza A(H1N1)pdm09, Canada, January 2019. Euro Surveill. 2019; 24(4). doi:10.2807/1560–7917.ES.2019.24.4.1900055.
Ramping up vaccination for the ebola outbreak spreading in the congo
Almost 500 people have died in the Democratic Republic of the Congo since an outbreak of Ebola was declared six months ago. The total number of cases exceeds 740 with 30% of them being children. >60,000 people have been vaccinated with an experimental Ebola vaccine rVSV-ZEBOV (Merck), and 120,000 more doses are ready for shipment.
The neighboring countries of Uganda, South Sudan and Rwanda have started – or are planning to do so – vaccinating front-line healthcare workers. rVSV-ZEBOV has not been licensed, but an application is pending with the FDA. The World Health Organization expects that there will be enough doses to fight the outbreak.
Positive phase 1 results for a chikungunya vaccine
The chikungunya vaccine candidate VLA1553 (Valneva) was safe and immunogenic according to interim results of a dose-escalation Phase 1 study. A single dose achieved 100% seroconversion rate across cohorts with no serious adverse events after four weeks. VLA1553 is a monovalent live, genetically attenuated vaccine designed for people over 1 year old. A single-dose immunization is hoped to be able to induce long-lasting antibody responses.
There is no licensed vaccine against the mosquito-borne chikungunya virus, which affects mostly tropical countries.
Early trial holds promise for a vaccine against pregnancy malaria
The malaria vaccine candidate PAMVAC was safe and immunogenic in a Phase 1 study involving 36 healthy adults.1 PAMVAC, a recombinant fragment of a Plasmodium falciparum protein responsible for binding to the placenta, is designed for prevention of pregnancy-associated malaria. The trial tested two dosage levels and three formulations in a double-blind randomized fashion.
“[The] vaccine is completely safe and induces the exact antibody response in the blood we want. Because it is the immune response that has been shown to be connected with protection from pregnancy malaria. The next step is to document that it prevents pregnancy malaria in African women who would otherwise have contracted the disease,” senior author Morten Nielsen of University of Copenhagen said in a press release.
1. Mordmüller B, Sulyok M, Egger-Adam D, Resende M, de Jongh WA, Jensen MH, Smedegaard HH, Ditlev SB, Soegaard M, Poulsen L, Dyring C, Calle CL, Knoblich A, Ibáñez J, Esen M, Deloron P, Ndam N, Issifou S, Houard S, Howard RF, Reed SG, Leroy O, Luty AJF, Theander TG, Kremsner PG, Salanti A, Nielsen MA. First-in-human, randomized, double-blind clinical trial of differentially adjuvanted PAMVAC, a vaccine candidate to prevent pregnancy-associated malaria. Clin Infect Dis. 2019. doi:10.1093/cid/ciy1140.
Rotavirus vaccination is correlated with decreased incidence of type 1 diabetes
The rotavirus vaccine might protect children from developing type 1 diabetes (T1D). A retrospective study from Australia compared prevalence of T1D before and after the introduction of routine oral rotavirus vaccination of infants in 2007 and found a 14% decline.1
Rotavirus infects pancreatic cells and its peptides display molecular mimicry with pancreatic β-cell autoantigens, thus presumably inducing the onset of the autoimmune T1D.
1. Perrett KP, Jachno K, Nolan TM, Harrison LC. Association of Rotavirus Vaccination With the Incidence of Type 1 Diabetes in Children. JAMA Pediatr. 2019. doi:10.1001/jamapediatrics.2018.4578.
FDA grants breakthrough designation to a 15-valent pneumococcal vaccine
The 15-valent pneumococcal vaccine candidate V114 (Merck) has received a breakthrough therapy designation by FDA. The aluminum-adjuvanted conjugate vaccine is in Phase 3 testing in children and adults. The designation applies to prevention of invasive pneumococcal disease caused by the vaccine strains in children aged 6 weeks to 18 years.
The decision is based on Phase 2 data indicating that V114 is non-inferior to the licensed Prevnar-13 in inducing protective antibody levels against the 13 Prevnar strains and immunogenic for two additional pneumococcal strains.