OYOsamu Yoshida

Osamu Yoshida

*This is an algorithmically generated author record based on publicly available information.

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Osamu Yoshida has a total of 118 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Nucleos(t)ide Analog–Therapeutic Vaccination Switch: A Novel Approach for Safe and Effective Treatment Discontinuation in HBeAg (-) Chronic Hepatitis B Patients

    by Sheikh Mohammad Fazle Akbar, Mamun Al Mahtab, Mohammad Abdur Rahim, Sheikh Mohammad Noor-E-Alam, Musarrat Mahtab, Ahmed Lutful Moben, Rokshana Begum, Dulal Chandra Das, Gerardo Guillen, Osamu Yoshida, et al.

    Background/Objective: Long-term nucleos(t)ide analog (NUC) therapy effectively suppresses hepatitis B virus (HBV) replication, but it rarely achieves a functional cure and typically requires lifelong administration. A major unmet need in chronic hepatitis B (CHB) is the development of safe and effective strategies to discontinue NUCs without compromising viral control or hepatic safety. This exploratory, randomized pilot study evaluated therapeutic immunization in the context of discontinuation of antiviral therapy in HBeAg-negative CHB. Methods: Twenty-six HBeAg-negative CHB patients receiving long-term therapy with NUCs were randomized to either discontinue NUCs and switch to HeberNasvac (NASVAC), a therapeutic vaccine (n = 13), or receive NASVAC in addition to NUCs (n = 13). Virological, serological, biochemical, and safety parameters were assessed during a 52-week primary follow-up. In particular, ALT and AST were evaluated every 2 weeks during the first 6 months after NUC discontinuation. An extended monitoring period from weeks 96 to 192 was designed to assess virological and biochemical variables. Results: At week 48, HBV DNA remained below 2000 IU/mL in 92.3% of patients who discontinued NUCs and received NASVAC and in 100% of those who received both NUCs and NASVAC. During extended follow-up, HBV DNA < 2000 IU/mL persisted in 84.6% and 76.9% of patients in the NUC discontinuation group at weeks 96 and 192, respectively, and in 100% of patients in the continuation group (NASVAC added to NUCs) at both time points. In the first 48 weeks after NUC discontinuation, NASVAC induced a limited but significant decline in serum quantitative HBsAg. Liver function, renal, and hematological parameters remained stable, without significant ALT abnormalities, biochemical exacerbations, fibrosis progression, or severe adverse events during primary or extended follow-up. None of the patients required restarting treatment. Conclusions: NASVAC-based immunotherapy demonstrated durable virological control, a limited but progressive reduction in qHBsAg, and a strong long-term safety profile following the complete withdrawal of antiviral therapy. This exploratory study suggests that NASVAC can be administered in the context of NUC discontinuation with an acceptable short- and long-term safety profile, but controlled trials are required to determine whether therapeutic vaccination contributes independently to sustained off-treatment viral control.

  • Open Access

    Therapeutic Vaccination in Chronic Hepatitis B: A Systematic Assessment by the HeberNasvac Therapeutic Vaccine Team

    by Julio Cesar Aguilar, Sheikh Mohammad Fazle Akbar, Mamun Al-Mahtab, Carlos Alberto Guzman, Guillermo Fernandez, Jorge Aguiar, Marie-Louise Michel, Maryline Bourgine, Maria Acelia Marrero, Stephanie Trittel, et al.

    The immune system is central 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, developing a vaccine with therapeutic properties represents a rational and cost-effective approach more than a romantic endeavor. This review systematically analyses the critical variables related to the safety, efficacy, and effectiveness of CHB treatments. HeberNasvac's experience is revisited to address the challenges and potentialities of therapeutic vaccines, as well as the current roadblocks in research and development, registration, and large-scale implementation.

  • Open Access

    Correction: Clinical features of patients with hepatocellular carcinoma treated with radiofrequency ablation therapy: developing a simple score to determine the need for immune-adjuvant therapy

    by Fujimasa Tada, Atsushi Hiraoka, Kosuke Nakatani, Kana Matsuoka, Mai Fukumoto, Takuya Matsuda, Emi Yanagihara, Hironobu Saneto, Taisei Murakami, Kei Onishi, et al.

  • Clinical features of patients with hepatocellular carcinoma treated with radiofrequency ablation therapy: developing a simple score to determine the need for immune-adjuvant therapy

    by Fujimasa Tada, Atsushi Hiraoka, Kosuke Nakatani, Kana Matsuoka, Mai Fukumoto, Takuya Matsuda, Emi Yanagihara, Hironobu Saneto, Taisei Murakami, Kei Onishi, et al.

    Background/aim Unresectable recurrence after curative treatments for hepatocellular carcinoma (HCC) is a life-limited event. Although the IMbrave050 trial (IM050) showed a favorable reduction in recurrence with adjuvant immune-combination chemotherapy, inclusion criteria of the radiofrequency ablation (RFA) group were lower risk than that of the resection group. This study aimed to elucidate the clinical features of patients treated with RFA, which really need adjuvant-chemotherapy. Methods From 2000 to 2022, 528 patients with Child–Pugh A and HCC within the Milan criteria (MC), who met the IM050 criteria for RFA and undergone resection or RFA, were enrolled (71 years, HCV:HBV:HBV/HCV:alcohol:others = 337:44:5:53:89, multi-tumor = 138, RFA:resection = 309:219). Unresectable recurrence was defined as beyond the MC. Risk factors for recurrence beyond the MC were retrospectively evaluated. Results Multivariate Cox-hazard analysis showed HCV-positive (HR 1.49), AFP-L3 > 10% (HR 1.75), and DCP > 100 mAU/mL (HR1.80) as significant prognostic factors for recurrence beyond the MC (each P < 0.05). Summing of positive factors (1 point for each) was used for scoring (AD-ON score), which showed increased positive rates for micro-hepatic vein invasion (score 0:1:2:3 = 0%:1.1%:6.6%:15.8%), micro-portal vein invasion (0:1:2:3 = 2.0%:12.1%:14.1%:31.6%), and poor differentiation (0:1:2:3 = 6.0%:6.7%:15.3%:15.8%) in the resection group associated with a greater score (each P < 0.01). In patients treated with RFA, those with greater AD-ON scores showed shorter time to recurrence beyond the MC, recurrence-free time, and overall survival (score 0:1:2:3 = no-estimation:97:66:23 months, 35:27:20:12 months, and 91:82:67:52 months, respectively, each P < 0.05). Conclusion HCC patients treated by RFA and with a high AD-ON score (≧2) should be considered for aggressive adjuvant-chemotherapy to prolong the period of recurrence beyond the MC.


  • Open Access

    Clinical and Pathological Features of Immune Checkpoint Inhibitor-induced Liver Injury in Comparison with Drug-induced Liver Injury and Autoimmune Hepatitis

    by Kotaro Sunago, Masanori Abe, Osamu Yoshida, Takao Watanabe, Yoshiko Nakamura, Yusuke Imai, Yohei Koizumi, Masashi Hirooka, Yoshio Tokumoto, Yoichi Hiasa

    Background and Aims: Immune checkpoint inhibitors may cause various types of organ damage as immune-related adverse events, of which, liver damage is the most common. Herein, we evaluated the clinicopathological features of immune checkpoint inhibitor-related liver injury and investigated the differences between immune checkpoint inhibitor-related liver injury and drug-induced liver injury or autoimmune hepatitis. Methods: We selected patients with ≥ grade 3 liver injury who were diagnosed with immune checkpoint inhibitor-related liver injury (n=15). Liver biopsies were performed in 10 of the 15 cases. We also selected cases in which a liver biopsy was performed and drug-induced liver injury (n=7) or autoimmune hepatitis [n=21: acute exacerbation (n=13) was diagnosed and cases of acute onset (n=8), in which liver function test results corresponded to ≥ grade 3]. Results: Portal fibrosis and periportal activity scores were significantly higher in the acute exacerbation autoimmune hepatitis group than in the other groups. Portal and lobular activity were not different between the groups. Plasma cell infiltration showed a higher trend in the autoimmune hepatitis group than in the other groups. Granuloma formations were seen in 90% of immune checkpoint inhibitor-related liver injury cases. The CD4/8 ratio was significantly lower in the immune checkpoint inhibitor-related liver injury group than in the other groups. Patients with bile duct injury had poorer response to corticosteroid therapy than those without. Conclusions: There are some obvious differences among immune checkpoint inhibitor-related liver injury, drug-induced liver injury, and autoimmune hepatitis in liver histology. Liver biopsy is helpful for the diagnosis and severity evaluation of liver injury.


  • Open Access

    Survival Improvements in Advanced Hepatocellular Carcinoma with Sequential Therapy by Era

    by Yoshiko Nakamura, Masashi Hirooka, Atsushi Hiraoka, Yohei Koizumi, Ryo Yano, Makoto Morita, Yuki Okazaki, Yusuke Imai, Hideko Ohama, Kana Hirooka, et al.

    Treatment modalities for advanced hepatocellular carcinoma (HCC) have changed dramatically, with systemic therapy as the primary option. However, the effect of sequential treatment on prognosis remains unclear. This retrospective study included patients who began systemic therapy between 2009 and 2022. The patients were separated into three groups according to systemic therapy commencement. The number of therapy lines, treatment efficacy, and overall survival (OS) were compared. Multivariate analyses of the prognostic factors were analyzed using the Cox proportional hazards model. Overall, 336 patients were included (period 1: 2009–2013, n = 86; period 2: 2014–2018, n = 132; period 3: 2019–2022, n = 118). A significant etiological trend was observed with decreasing viral hepatitis-related HCC and increasing non-viral hepatitis-related HCC. Across periods 1–3, the proportion of patients who were administered >2 lines progressively increased (1.2%, 12.9%, and 17.0%, respectively; p < 0.001) and the median OS was significantly prolonged (14.3, 16.8, and 31.0 months; p < 0.001). The use of <3 lines, the non-complete and partial response of the first line, modified albumin–bilirubin at grade 2b or 3, an intrahepatic tumor number ≥ 5, extrahepatic metastasis, and alpha-fetoprotein at ≥400 ng/mL were the strongest factors associated with shorter OS. Sequential therapies have contributed to significant improvements in HCC prognosis, suggesting that sequential treatment post-progression is worthwhile for better survival.


  • Open Access

    Intranasal HBsAg/HBcAg-Containing Vaccine Induces Neutralizing Anti-HBs Production in Hepatitis B Vaccine Non-Responders

    by Kana Shiraishi, Osamu Yoshida, Yusuke Imai, Sheikh Mohammad Fazle Akbar, Takahiro Sanada, Michinori Kohara, Takashi Miyazaki, Taizou Kamishita, Teruki Miyake, Masashi Hirooka, et al.

    Hepatitis B vaccine induces the production of antibodies against hepatitis B surface antigen (anti-HBs) and prevents hepatitis B virus (HBV) infection. However, 5–10% of individuals cannot develop anti-HBs even after multiple vaccinations (HB vaccine non-responders). We developed an intranasal vaccine containing both HBs antigen (HBsAg) and HB core antigen (HBcAg) and mixed it with a viscosity enhancer, carboxyl vinyl polymer (CVP-NASVAC). Here, we investigated the prophylactic capacity of CVP-NASVAC in HB vaccine non-responders. Thirty-four HB vaccine non-responders were administered three doses of intranasal CVP-NASVAC. The prophylactic capacity of CVP-NASVAC was assessed by evaluating the induction of anti-HBs and anti-HBc (IgA and IgG) production, HBV-neutralization activity of sera, and induction of HBs- and HBc-specific cytotoxic T lymphocytes (CTLs). After CVP-NASVAC administration, anti-HBs and anti-HBc production were induced in 31/34 and 27/34 patients, respectively. IgA anti-HBs and anti-HBc titers significantly increased after CVP-NASVAC vaccination. HBV-neutralizing activity in vitro was confirmed in the sera of 26/29 CVP-NASVAC-administered participants. HBs- and HBc-specific CTL counts substantially increased after the CVP-NASVAC administration. Mild adverse events were observed in 9/34 participants; no serious adverse events were reported. Thus, CVP-NASVAC could be a beneficial vaccine for HB vaccine non-responders.


  • Lymphatic drainage dysfunction via narrowing of the lumen of cisterna chyli and thoracic duct after luminal dilation

    by Ryo Yano, Masashi Hirooka, Yohei Koizumi, Yoshiko Nakamura, Yusuke Imai, Makoto Morita, Yuki Okazaki, Takao Watanabe, Osamu Yoshida, Yoshio Tokumoto, et al.

    Background The chronological pattern of extrahepatic lymphatic vessel progression in the course of chronic liver disease has not been clarified. This study aimed to clarify the chronological changes in lymphatic vessels with liver disease progression. Methods This was a prospective cross-sectional study that enrolled a total of 199 patients. The maximum diameter of the cisterna chyli (CC) or terminal thoracic duct (tTD) was measured using computed tomography or ultrasonography, respectively. Changes in the maximum diameters of the CC and tTD were evaluated with patients with chronic liver disease as the pilot set (n = 138). Subsequently, we examined whether CC/tTD could be used to re-allocate unclassified patients by the Baveno-VII criteria to appropriately diagnose clinically significant portal hypertension (CSPH) in the pilot and validation sets. Results In the pilot set, a scatter-plot showed that both CC and tTD were narrowed as terminal features in chronic liver disease after dilation. Because there was a significant correlation between the CC diameter and hepatic venous pressure gradient (r = 0.724) in unclassified patients, the diagnostic value of CC and tTD for CSPH was good (AUC: 0.961 and 0.913, respectively). After re-allocation, 68 and 27 unclassified patients were reduced to 4 and 5 in the pilot and validation sets, respectively. Conclusion Both the CC and tTD narrow in the course of liver disease after dilation. Moreover, the maximum diameter of the CC and tTD can be used to re-allocate patients who are unclassified according to the Baveno-VII criteria. Clinical trial number UMIN trial no. 000044857. Graphical Abstract


  • Open Access

    Development of Therapy Based on the Exploration of Biological Events Underlying the Pathogenetic Mechanisms of Chronic Hepatitis B Infection

    by Sheikh Mohammad Fazle Akbar, Mamun Al Mahtab, Osamu Yoshida, Julio Aguilar, Guillen Nieto Gerardo, Yoichi Hiasa

    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. Potent preventive vaccines have already restricted new HBV infections, and several drugs are available to treat chronic HBV infections. However, the positive impacts of these drugs have been recorded in only a few patients with chronic HBV infection. These drugs do not show long-term efficacy and cannot halt the progression to complications. Thus, more effective and evidence-based therapeutic strategies need to be urgently developed for patients with chronic HBV infection. CHB is a pathological entity induced by HBV that progresses due to impaired host immunity. This indicates the inherent limitations of antiviral-drug-based monotherapy for treating patients with chronic HBV infection. Additionally, commercially available antiviral drugs are not available to patients in developing and resource-constrained countries, posing a challenge to achieving the following WHO goal: “Elimination of Hepatitis by 2030”. As such, this review aimed to provide insights regarding evidence-based and effective management strategies for chronic HBV infection.


  • Open Access

    Antiviral Response across Genotypes after Treatment of Chronic Hepatitis B Patients with the Therapeutic Vaccine NASVAC or Pegylated Interferon

    by Mamun Al-Mahtab, Sheikh Mohammad Fazle Akbar, Osamu Yoshida, Julio Cesar Aguilar, Gerardo Guillen, Yoichi Hiasa

    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. The antiviral effects and alanine aminotransferase levels were not significantly different among different HBV genotypes in NASVAC-treated patients. However, a significantly higher proportion of genotype-D patients receiving NASVAC showed better therapeutic effects, compared to genotype-D patients receiving Peg-IFN, with a marked difference of 44%. In conclusion, NASVAC seems to be a better alternative to Peg-IFN, especially in patients with HBV genotype-D patients. This reflects the attractiveness of NASVAC in countries where genotype D is highly prevalent. The mechanisms underlying the effect of HBV genotype are being studied in a new clinical trial.