Publications by authors named "Gerardo Guillen"

Unlabelled: The immune system plays a central role in controlling acute hepatitis B infection and in patients resolving chronic hepatitis B (CHB). Given that 221 million (75%) of CHB patients reside in low- and middle-income countries, the development of a vaccine with therapeutic properties represents a rational and cost-effective approach more than a romantic endeavor. This review systematically analyzes the key variables related to the safety, efficacy, and effectiveness of CHB treatments.

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The Hepatitis B core antigen (HBcAg) has been used as a carrier of several heterologous protein fragments based on its capacity to form virus-like particles (VLPs) and to activate innate and adaptive immune responses. In the present work, two chimeric proteins were designed as potential pancorona vaccine candidates, comprising the N- or C- terminal domain of SARS-CoV-2 nucleocapsid (N) protein fused to HBcAg. The recombinant proteins, obtained in E.

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Article Synopsis
  • * The study found that both vaccines had no severe adverse effects and a high percentage of participants showed increased antibody responses after receiving the booster, with 83.3% for Abdala in Phase 1 and 88.6% in Phase 2.
  • * Both vaccines exceeded the immunogenicity goals set by the trial, with significant increases in antibody levels and neutralizing capacity against SARS-CoV-2 variants after the booster dose, indicating strong efficacy.
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Zika virus (ZIKV) infection remains a global public health problem. After the "Public Health Emergencies of International Concern" declared in February 2016, the incidence of new infections by this pathogen has been decreasing in many areas. However, there is still a likely risk that ZIKV will spread to more countries.

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A chimeric protein, formed by two fragments of the conserved nucleocapsid (N) and S2 proteins from SARS-CoV-2, was obtained as a recombinant construct in . The N fragment belongs to the C-terminal domain whereas the S2 fragment spans the fibre structure in the post-fusion conformation of the spike protein. The resultant protein, named S2NDH, was able to form spherical particles of 10 nm, which forms aggregates upon mixture with the CpG ODN-39M.

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Unlabelled: HeberNasvac is a recently developed therapeutic vaccine for chronic hepatitis B (CHB) administered by intranasal (IN) and subcutaneous (SC) routes in a 14 days/10 doses schedule. To compare different schedules and routes of immunizations, a group of patients received four different vaccination regimens in a placebo-controlled factorial study. Subsequently, patients were followed for a minimum time of 48 weeks.

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Zika virus infection continues to be a global concern for human health due to the high-risk association of the disease with neurological disorders and microcephaly in newborn. Nowadays, no vaccine or specific antiviral treatment is available, and the development of safe and effective vaccines is yet a challenge. In this study, we obtained a novel subunit vaccine that combines two regions of zika genome, domain III of the envelope and the capsid, in a chimeric protein in E.

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According to the World Health Organization (WHO), an estimated 296 million people are chronically infected with hepatitis B virus (HBV). Approximately 15-25% of these people develop complications such as advanced chronic liver diseases (ACLDs). Mortality due to HBV-related complications accounted for an estimated 882,000 deaths in 2019.

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Article Synopsis
  • Researchers are aiming to develop a more effective vaccine against SARS-CoV-2 due to new variants and potential zoonotic events.
  • The study tested a nasal vaccine formulation in mice, combining nucleocapsid and RBD proteins with different adjuvants to enhance immune response.
  • Results showed that this vaccine induces high levels of antibodies capable of neutralizing multiple variants of SARS-CoV-2, suggesting its potential role in a broader coronavirus vaccine strategy.
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An open-level, randomized and treatment-controlled clinical trial has shown that a therapeutic vaccine containing hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) (NASVAC) is endowed with antiviral and liver protecting capacity and is safer than pegylated interferon (Peg-IFN) in patients with chronic hepatitis B (CHB). The present study provides information about the role of the hepatitis B virus (HBV) genotype in this phase III clinical trial. From a total of 160 patients enrolled in this trial, the HBV genotypes of 133 patients were characterized, and NASVAC induced a stronger antiviral effect (HBV DNA reduction below 250 copies per mL) than Peg-IFN.

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Introduction: There is a pressing need to develop novel drugs for treating patients with chronic hepatitis B (CHB), as commercially available antiviral drugs are endowed with safety and efficacy concerns.

Methods: A phase III clinical trial was conducted with a therapeutic vaccine containing two antigens of the hepatitis B virus (HBV; named NASVAC) in 78 patients with CHB expressing both HBV DNA and elevated levels of alanine aminotransferase (ALT) in the blood. Five years after the end of treatment (EOT), 60 NASVAC-recipient patients were enrolled in this long-term follow-up study to evaluate the safety, antiviral potential, and liver-protective capacity of NASVAC.

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Article Synopsis
  • The study aimed to assess the safety and efficacy of a new therapeutic vaccine called CVP-NASVAC for patients with chronic hepatitis B (CHB), focusing on achieving HBsAg loss and anti-HBs acquisition as treatment goals.
  • A phase IIa clinical trial was conducted, where patients received CVP-NASVAC through nasal injection over 10 sessions, and were followed for 18 months to evaluate changes in HBsAg levels and the presence of anti-HBs antibodies.
  • Results showed significant reductions in HBsAg among both treated groups, with 40.7% of treated patients developing anti-HBs antibodies, and 9.5% achieving a functional cure, indicating CVP-NASVAC
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Chronic hepatitis B (CHB) is a highly complicated pathological process in which the disease is initiated by the hepatitis B virus (HBV); however, host immune responses are primarily responsible for variable extents of liver damage. If the patients with CHB remain untreated, many CHB patients will eventually develop complications like cirrhosis of the liver (LC) and hepatocellular carcinoma (HCC). In 2019, an estimated 882,000 patients died due to HBV-related complications worldwide.

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Since the beginning of the COVID-19 pandemic, the development of effective vaccines against this pathogen has been a priority for the scientific community. Several strategies have been developed including vaccines based on recombinant viral protein fragments. The receptor-binding domain (RBD) in the S1 subunit of S protein has been considered one of the main targets of neutralizing antibodies.

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The objective of the present study was to assess the safety and efficacy of a therapeutic vaccine containing both HBsAg and HBcAg (NASVAC) in patients with chronic hepatitis B (CHB) three years after the end of treatment (EOT) as a follow-up of a phase III clinical trial. NASVAC was administered ten times by the nasal route and five times by subcutaneous injection. A total of 59 patients with CHB were enrolled.

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A phase III clinical trial in treatment-naïve patients with chronic hepatitis B (CHB) revealed the safety and considerable therapeutic efficacy of a vaccine containing both hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) (NASVAC) at the end of treatment (EOT) and 24 weeks after EOT. Two years after EOT, we checked HBV DNA, alanine aminotransferase (ALT), and hepatitis B e antigen (HBeAg). The data reveal that 33 of 66 NASVAC-recipient CHB patients became negative for HBV DNA in the blood two years after EOT.

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Introduction: More than 180 million people have been infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and more than 4 million coronavirus disease-2019 (COVID-19) patients have died in 1.5 years of the pandemic. A novel therapeutic vaccine (NASVAC) has shown to be safe and to have immunomodulating and antiviral properties against chronic hepatitis B (CHB).

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Subunit vaccines based on the receptor-binding domain (RBD) of the spike protein of SARS-CoV-2 provide one of the most promising strategies to fight the COVID-19 pandemic. The detailed characterization of the protein primary structure by mass spectrometry (MS) is mandatory, as described in ICHQ6B guidelines. In this work, several recombinant RBD proteins produced in five expression systems were characterized using a non-conventional protocol known as in-solution buffer-free digestion (BFD).

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Unlabelled: The coronavirus 2019 (COVID-19) pandemic has resulted in 168 million cases and about 3.5 million deaths (as of May 26, 2021) during the last 18 months. These 18 months of the COVID-19 pandemic have been characterized by phases or waves of new cases, the emergence of new variants of the deadly virus, and several new complications.

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The instrumental role of CK2 in the SARS-CoV-2 infection has pointed out this protein kinase as promising therapeutic target in COVID-19. Anti-SARS-CoV-2 activity has been reported by CK2 inhibitors ; however, no anti-CK2 clinical approach has been investigated in COVID-19. This trial aimed to explore the safety and putative clinical benefit of CIGB-325, an anti-CK2 peptide previously assessed in cancer patients.

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Dengue is one of the most important diseases transmitted by mosquitoes. Dengvaxia®, a vaccine registered in several countries, cannot be administered to non-immune individuals and children younger than 9 years old, due to safety reasons. There are two vaccine candidates in phase 3 efficacy trials, but their registration date is completely unknown at this moment.

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The development of live-attenuated vaccines against Dengue virus (DENV) has been problematic. Dengvaxia, licensed in several countries where DENV is endemic, has shown low efficacy profiles and there are safety concerns prohibiting its administration to children younger than 9 years old, and the live-attenuated tetravalent vaccine (LATV) developed by NIAID has proven too reactogenic during clinical trialing. In this work we examined whether the combination of TV005, a LATV-derived formulation, with Tetra DIIIC, a subunit vaccine candidate based on fusion proteins derived from structural proteins from all four DENV serotypes, can overcome the respective limitations of these two vaccine approaches.

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Heberprovac is a GnRH based vaccine candidate containing 2.4 mg of the GnRHm1-TT peptide as the main active principle; 245 μg of the very small size proteoliposomes adjuvant (VSSP); and 350 μL of Montanide ISA 51 VG oil adjuvant. The aim of this study was to assess the safety and tolerance of the Heberprovac in advanced prostate cancer patients as well as its capacity to induce anti-GnRH antibodies, the subsequent effects on serum levels of testosterone and PSA and the patient overall survival.

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Introduction: Dengue fever remains as a health problem worldwide. Although Dengvaxia®, was registered in several countries, the results after the immunization of people suggest an increase of risk in non-immune persons and children younger than 9 years old. No other vaccine is registered so far, thus the development of a safe and effective vaccine continues to be a priority for the WHO and the scientific community.

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Context: Current drugs for chronic hepatitis B therapy have a poor efficacy in terms of post-treatment sustained viral suppression and generate important side effects during and after therapy. Therapeutic vaccination with HBV antigens is an attractive alternative to test.

Objective: Evaluating the efficacy of a therapeutic vaccine candidate (designated NASVAC) containing both hepatitis B surface antigen (HBsAg) and core antigen (HBcAg) versus pegylated interferon (Peg-IFN) in naïve chronic hepatitis B patients.

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