Vabiotech (Vietnam)

The World Health Organization declared the COVID-19 disease as a pandemic requiring a rapid response. Through online search, direct communication with network members and an internal survey, engagements of developing countries' vaccine manufacturers' network members in the research and development of COVID-19 vaccines and their capacities in the manufacturing, fill-finish and distribution of vaccines were assessed. Currently, 19 network members engaged in research and development of COVID-19 vaccines, using six principal technology platforms. In addition, an internal survey showed that the number of vaccines supplied collectively by 37 members, in 2018-19, was about 3.5 billion doses annually. Almost a third of network members having vaccines prequalified by the World Health Organization comply with international regulations and mechanisms to distribute vaccines across borders. The use of existing manufacturing, fill-finish and distribution capabilities can support an efficient roll-out of vaccines against COVID-19, while maintaining supply security of existing vaccines for on-going immunization programmes.

Sexually transmitted diseases are major causes of infertility, ectopic pregnancy, and premature birth. Here, we developed a new multiplex real-time polymerase chain reaction (PCR) assay for the simultaneous detection of nine major sexually transmitted infections (STIs) found in Vietnamese women, including Chlamydia trachomatis, Neisseria gonorrhoeae, Gardnerella vaginalis, Trichomonas vaginalis, Candida albicans, Mycoplasma hominis, Mycoplasma genitalium, and human alphaherpesviruses 1 and 2. A panel containing three tubes × three pathogens/tube was predesigned based on double-quenched TaqMan probes to increase detection sensitivity. There was no cross-reactivity among the nine STIs and other non-targeted microorganisms. Depending on each pathogen, the agreement with commercial kits, sensitivity, specificity, repeatability and reproducibility coefficient of variation (CV), and limit of detection of the developed real-time PCR assay were 99.0%-100%, 92.9%-100%, 100%, <3%, and 8-58 copies/reaction, respectively. One assay cost only 2.34 USD. Application of the assay for the detection of the nine STIs in 535 vaginal swab samples collected from women in Vietnam yielded 532 positive cases (99.44%). Among the positive samples, 37.76% had one pathogen, with G. vaginalis (33.83%) as the most prevalent; 46.36% had two pathogens, with G. vaginalis + C. albicans as the most prevalent combination (38.13%); and 11.78%, 2.99%, and 0.56% had three, four, and five pathogens, respectively. In conclusion, the developed assay represents a sensitive and cost-effective molecular diagnostic tool for the detection of major STIs in Vietnam and is a model for the development of panel detections of common STIs in other countries.

BACKGROUND: Up to 30% of acute viral hepatitis has no known etiology. To determine the disease etiology in patients with acute hepatitis of unknown etiology (HUE), serum specimens were obtained from 38 patients residing in the United Kingdom and Vietnam and from 26 healthy US blood donors. All specimens tested negative for known viral infections causing hepatitis, using commercially available serological and nucleic acid assays. METHODS: Specimens were processed by sequence-independent complementary DNA amplification and next-generation sequencing (NGS). Sufficient material for individual NGS libraries was obtained from 12 HUE cases and 26 blood donors; the remaining HUE cases were sequenced as a pool. Read mapping was done by targeted and de novo assembly. RESULTS: Sequences from hepatitis B virus (HBV) were detected in 7 individuals with HUE (58.3%) and the pooled library, and hepatitis E virus (HEV) was detected in 2 individuals with HUE (16.7%) and the pooled library. Both HEV-positive cases were coinfected with HBV. HBV sequences belonged to genotypes A, D, or G, and HEV sequences belonged to genotype 3. No known hepatotropic viruses were detected in the tested normal human sera. CONCLUSIONS: NGS-based detection of HBV and HEV infections is more sensitive than using commercially available assays. HBV and HEV may be cryptically associated with HUE.

New vaccines are required to meet the public health challenges of the next generation and many unmet global health needs can be addressed by developing countries vaccine manufacturers such as lower-cost vaccines based on single-dose, thermostable formulations, efficacious in children with compromised gastrointestinal tracts. GMP compliance is also a challenge, as sometimes innovation and clinical development focus is not accompanied by command of scale-up and quality assurance for large volume manufacturing and supply. Identifying and addressing such challenges, beyond cost and cold-chain space, including safety considerations and health worker behavior, regulatory alliances and harmonization to foster access to vaccines, will help countries to ensure sustainable immunization. There needs to be continuous and close management of the global vaccine supply both at national and international levels, requiring careful risk management, coordination and cooperation with manufacturers. Successful partnership models based on sharing a common goal, mutual respect and good communication were discussed among stakeholders.

Purpose: We evaluated the immunogenicity and safety of Rabivax-S (Pitman-Moore 3218 strain) by intramuscular (IM) and intradermal (ID) routes in Vietnam. Materials and Methods: We conducted an open-label, randomized, phase 4, single-center clinical trial in healthy individuals aged five to 60 years divided into two groups according to age (5-15 years old and 16-60 years old). They were randomized to receive 3 doses of Rabivax-S IM 1 mL) or Rabivax-S ID (0.1 mL) in 1:1 ratio on days 0, 7, and 21. Adverse events (AEs) were collected for 7 days after each dose and rabies-neutralizing antibody levels were measured were measured by RFFIT on days 0, 21 and 42. Results: Totally 220 participants aged 5-15 years old (117 participants) and 16-60 years old (103 participants). The seroconversion rates of antibodies among the two groups (IM and ID doses) were all 100.0% on D21 and D42/42. On D21 and D42/42, the geometric mean concentration of the two groups was much higher than the immune protection level of 0.5 IU/mL. There were no AEs or serious AEs recorded in all four visits. Unsolicited AEs were reported by 3% of participants. The most common AEs during seven days after each dose were fever, pain, and erythema. Mostly mild local and systemic AEs were reported across the two groups and all resolved without sequelae. Conclusion: The study results conclusively demonstrate that the complete regimen of both the IM and ID 3-dose series Rabivax-S was found to be clinically safe and immunogenic. After this study, Rabivax-S is now available in Vietnam and can be used for pre- and post-exposure prophylaxis. Clinical Trials Registration: ClinicalTrials.gov Identifier: NCT05937113.

Japanese encephalitis (JE) is one of the most important infectious disease in Southeast Asia and the Pacifc region and more than 3 billion people are living in endemic areas. The annual incidence is estimated to be 60,000 cases/year of which 15,000 deaths, 50% of the people survive with neurological sequelae. Since 1997, Vietnam has produced and used mouse brain - derived (MB) inactivated Japanese encephalitis vaccine (JEVAX®) for children 1 - 5 years of age under the Expanded programme on immunization (EPI). In 2006, VABIOTECH started the research and development of vero cell-derived inactivated JE vaccine (JECEVAX). The clinical trial phases I, II &amp; IIB were conducted successfully and the phase III was completed in January 2019. The study participants included 655 healthy infants aged 9 - 24 months were immunized with JECEVAX testing vaccine, and JEVAX® control vaccine. The results showed that both vaccines were safe with good tolerability in children. The seroconversion rates of JECEVAX (n = 547) were 99.6 - 100%, compared with JEVAX® (n =108) were 99 - 100%. The GMT titer of JECEVAX and JEVAX® after the second dose was 2.07log and 2.02log after the third dose, the neutralizing antibody (PRNT50) increased to 3.04log and 3.19log respectively. The registration dossier with the MOH of Vietnam is being fnalized before scaling up the production to prevent JE disease with JECEVAX high qualifed second generation vaccine.

Introduction: This study aimed to compare the efficacy of Copy Number Variation sequencing (CNV-Seq) with that of traditional karyotyping in prenatal diagnostics by assessing their concordance and ability to identify aneuploidies and structural abnormalities in fetal chromosomes. Methodology: We analyzed 177 amniotic fluid samples from pregnant women who were at or beyond 16 weeks of gestation, utilizing both CNV-Seq and karyotyping to evaluate their detection capabilities. Results: CNV-Seq identified chromosomal abnormalities in 46 cases (26.0%), demonstrating a higher detection rate compared to karyotyping, which found abnormalities in 40 cases (22.6%). CNV-Seq showed 100% concordance in identifying conditions such as trisomy 21, 18, 13, monosomy X, and 47, XXY. It also detected three mosaic cases and 13 copy number variations (CNVs) involving deletions or duplications that were not fully concordant with karyotyping results. Notably, CNV-Seq had a detection rate of 3.95% (7/177) for pathogenic or likely pathogenic chromosomal anomalies, and variants of uncertain significance (VUS) constituted 3.39% (6/177) of the findings. Conclusion: CNV-Seq improves the precision of prenatal diagnostics and broadens the scope for informed clinical decision-making, especially in managing pregnancies with detected abnormalities. The integration of CNV-Seq with traditional karyotyping addresses gaps in detection and supports a more comprehensive approach to prenatal care. Further studies should aim to include a broader and more diverse population to validate and expand upon these results.

Background: Screening for Down syndrome (DS) conducted in the first trimester provides essential information for expectant parents and healthcare providers to make informed decisions about further diagnostic testing and potential interventions. Objectives: This study aimed to explore the preferences and influential factors for subsequent screening and diagnostic tests among Vietnamese women at risk for DS, including non-invasive prenatal testing (NIPT) and amniocentesis. Methods: A cross-sectional study was conducted from January 2022 to January 2023 with 125 pregnant women selected through convenience sampling at a public hospital in Vietnam. Data were collected from standardized medical records and analysis forms for each participant who underwent first-trimester Double test screening at the healthcare center. Participants were stratified by DS risk thresholds ranging from 1/51 to 1/1000. Chi-square and Fisher's exact tests were used to compare the acceptance rate of screening tests between groups. Logistic regression was utilized to explore factors related to participants' preferences. Results: The majority (71.2%) of participants were under 35 years old. The prevalence of consenting to further tests was 69.7% in the high-risk group (95% CI: [54.02%, 85.38%]) and 67.4% in the moderate-risk group (95% CI: [57.81%, 76.97%]), with all participants in the moderate-risk group selecting NIPT. In the high-risk group, 65.22% preferred NIPT and 34.78% chose amniocentesis. The key reasons for declining further testing included a preference for ultrasound monitoring (70%), financial constraints (7.5%), and religious beliefs (10%). Chi-square analysis indicated a statistically significant variation in diagnostic test selection by age group, with younger women more likely to choose NIPT (P &lt; 0.0001). Conclusions: There is a marked preference for NIPT over invasive methods, especially among younger moderately risk women. These results emphasize the need for individualized counseling and education, as well as increased support for noninvasive testing options through healthcare policy and insurance coverage.

New vaccines are required to meet the public health challenges of the next generation and many unmet global health needs can be addressed by developing countries vaccine manufacturers such as lower-cost vaccines based on single-dose, thermostable formulations, efficacious in children with compromised gastrointestinal tracts. GMP compliance is also a challenge, as sometimes innovation and clinical development focus is not accompanied by command of scale-up and quality assurance for large volume manufacturing and supply. Identifying and addressing such challenges, beyond cost and cold-chain space, including safety considerations and health worker behavior, regulatory alliances and harmonization to foster access to vaccines, will help countries to ensure sustainable immunization. There needs to be continuous and close management of the global vaccine supply both at national and international levels, requiring careful risk management, coordination and cooperation with manufacturers. Successful partnership models based on sharing a common goal, mutual respect and good communication were discussed among stakeholders.

BACKGROUND: Pneumococcal conjugate vaccines (PCVs) prevent severe disease in children, but high costs limit access. PCV10-SII (PNEUMOSIL), a 10-valent PCV prequalified by the World Health Organization (WHO) in 2019, offers a cost-effective alternative. This study assessed its safety and immunogenicity in Vietnamese children aged 6 weeks-24 months. METHODS: An open-label, single-arm study enrolled 304 children in three age groups: 6 weeks-6 months (n = 151), >6-12 months (n = 76), and >12-24 months (n = 77). Participants received two or three doses. Safety was evaluated through immediate reactions, adverse events (AEs), serious adverse events (SAEs), and withdrawals. Immunogenicity was measured 28 days after the final dose using serotype-specific IgG geometric mean concentrations (GMCs), opsonophagocytic activity (OPA) titers, and seroresponse rates. The trial was approved by the IRB of the National Ethics Council (code: No. 75/CN-HĐĐĐ on date 4 June 2021) and was registered with ClinicalTrials.gov, NCT05140720. RESULTS: Of 304 enrolled participants, 294 (96.7%) completed follow-up. No immediate adverse events or serious adverse events occurred. Unsolicited adverse events were reported in 17%, mainly respiratory, while serious adverse events occurred in 4%. Mild local/systemic reactions (e.g., injection site pain, crying) resolved without sequelae. Immunogenicity was strong, with GMCs 1.8-9.11 µg/mL, GMTs 277.8-22,342, and seroresponse rates >90% for 9 of 10 serotypes, serotype 6B demonstrated a slightly lower seroresponse rate of 88.6%. CONCLUSIONS: PCV10-SII demonstrated favorable safety and robust immunogenicity, supporting its inclusion in national immunization programs as an affordable option for pneumococcal disease prevention.

Introducción: El dengue es una de las enfermedades más importantes trasmitida por mosquitos; sin embargo solo existe una vacuna licenciada, la cual está registrada en 20 países. Sin embargo, la vacuna no podrá ser administrada en niños menores de nueve años de edad, dado el elevado riesgo de hospitalización observado en este grupo etario. Por lo tanto, el desarrollo de nuevos candidatos vacunales y estrategias de inmunización continúan siendo una prioridad para la Organización Mundial de la Salud y la comunidad científica. Objetivos: el presente trabajo describe los resultados obtenidos de la combinación en esquemas complementarios de dos tipos de candidatos vacunales: las proteínas recombinantes y los virus vivos atenuados. En un primer acercamiento, el candidato vacunal tetravalente Tetra DIIIC se administró en primates no humanos previamente infectados con virus dengue. En un segundo estudio se evaluó la combinación de Tetra DIIIC y la formulación tetravalente de virus vivos atenuados por vía molecular TV005, desarrollada por el Instituto de Salud de los Estados Unidos y licenciada a la compañía vietnamita Vabiotech. Métodos: Se utilizaron en los estudios primates no humanos sanos de la especie Macaca mulatta. El candidato vacunal tetravalente Tetra DIIIC, consiste en las proteínas recombinantes DIIIC-1-DIIIC4, correspondientes a los cuatro serotipos del virus dengue, adyuvadas en alúmina. La formulación tetravalente de virus vivos atenuados TV005 por Vabiotech incluyó las cepas virales DENV-1 Nauru/74 (WP), DENV-2 Tonga/74, DENV-3 Sleman/78 y DENV-4 Dominica/81. Resultados: Los resultados demuestran que la administración de Tetra DIIIC ocho meses después de la infección pudo activar la respuesta específica de las células B y T contra el DENV. Además, se demostró que los animales inoculados con Tetra DIIIC (una o dos dosis) y luego inmunizados con TV005 desarrollan una respuesta de anticuerpos protectora contra los cuatro serotipos del DENV y que la respuesta inmunológica generada por la Tetra DIIIC reduce la viremia LATV significativamente, lo cual pudiera reducir la reactogenicidad que ha afectado a este último durante los ensayos clínicos. Los resultados aquí descritos resaltan la posibilidad de combinar nuestro candidato vacunal Tetra DIIIC con la vacuna tetravalente del virus vivo atenuado en una estrategia reforzada de inmunización. El presente estudio respalda las estrategias reforzadas como alternativa y enfoques promisorios que solucionan los problemas asociados a cada antígeno individual incluido en la combinación.

Introduction: Cervical cancer, predominantly associated with high-risk Human Papillomavirus (HPV) types 16 and 18, presents a substantial public health challenge, particularly impacting women in low and middle-income countries. This study aims to address a vital knowledge gap by examining the relationship between age, menstrual status, and histopathological types of cervical carcinoma in Vietnamese patients. Methods: The research was conducted at a major provincial public maternity and pediatric hospital in Vietnam from August 2019 to July 2022. A total of 48 adult female patients with histopathologically confirmed invasive cervical carcinoma were included in this combined retrospective and prospective observational study. Demographic and clinical data were collected and analyzed using univariate analysis to determine the associations between different factors and histopathological types. Statistical significance was set at p &lt; 0.05, with odds ratios (ORs), 95% confidence intervals (CIs), and p-values calculated accordingly. Results: The results revealed that squamous cell carcinoma (SCC) was the most common histopathological type (81.2%), followed by adenocarcinoma (12.5%) and adenosquamous carcinoma (6.2%). Within the SCC subtype, non-keratinizing SCC was the most prevalent (69.2%). Individuals aged 50 years and older had significantly higher odds of being diagnosed with SCC compared to those aged 39 years or younger (OR = 10.40, 95% CI: 1.48-73.00, p = 0.02). Menopausal individuals also had significantly increased odds of SCC compared to those who were menstruating (OR = 10.35, 95% CI: 1.18-90.95, p = 0.04). Conclusion: These findings underscore the significant correlations between age, menstrual status, and the prevalence of SCC in Vietnamese patients, underscoring the importance of targeted public health initiatives. The study provides crucial insights that could inform the development of effective prevention and management strategies in Vietnam and similar settings.

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