Management of hepatitis B in special populations

Design and analysis considerations for early phase clinical trials in hepatitis B (HBV) cure research: the ACTG A5394 study in persons with both HIV and HBV

With growing interest and efforts to achieve a hepatitis B (HBV) cure, HBV therapeutics have increasingly entered the clinical testing phase. In designing an early phase clinical trial aimed at HBV cure, the heterogeneity in participants and the choice of a biomarker endpoint that signals a cure requires careful consideration. We describe the key elements to consider during the development of HBV clinical trials aimed at a functional cure, and how we have addressed them in the design of a phase II AIDS Clinical Trials Group (ACTG) study, A5394 (NCT05551273). The trial we present is for persons with both HIV and HBV, a unique population that has much to gain from an HBV cure. Our decisions on the design elements are specific to the study agent and the targeted population, but our deliberations may be informative in the emerging field of early phase HBV trials aimed at cure.

New Developments and Challenges in Liver Transplantation

Liver disease is increasing in incidence and is the third most common cause of premature death in the United Kingdom and fourth in the United States. Liver disease accounts for 2 million deaths globally each year. Three-quarters of patients with liver disease are diagnosed at a late stage, with liver transplantation as the only definitive treatment. Thomas E. Starzl performed the first human liver transplant 60 years ago. It has since become an established treatment for end-stage liver disease, both acute and chronic, including metabolic diseases and primary and, at present piloting, secondary liver cancer. Advances in surgical and anaesthetic techniques, refined indications and contra-indications to transplantation, improved donor selection, immunosuppression and prognostic scoring have allowed the outcomes of liver transplantation to improve year on year. However, there are many limitations to liver transplantation. This review describes the milestones that have occurred in the development of liver transplantation, the current limitations and the ongoing research aimed at overcoming these challenges.

Possible Association between Genetic Diversity of Hepatitis B Virus and Its Effect on the Detection Rate of Hepatitis B Virus DNA in the Placenta and Fetus

Background: The prevalence of HBV infection and HBV genotypes varies from country to country, and the role of HBV genotypes in the presence of HBV in the placenta and fetus has never been explored. This study was conducted to (1) identify HBV genotypes, and their frequencies, that infected Northern Thai pregnant women; (2) evaluate the association between HBV genotypes and the detection rate of HBV DNA in the placenta and fetus; (3) evaluate the association between specific mutations of the HBV genome and HBV DNA detection in placental tissue; and (4) identify the mutation of the HBV genome that might occur between maternal blood, placenta, and cord blood. Methods: Stored samples of the maternal blood, placental tissue, and cord blood that were collected from 145 HBsAg-positive pregnant Thai women were analyzed to identify HBV DNA. Results: Approximately 25% of infected mothers had fetal HBV DNA detection, including cases with concomitant HBV DNA detection in the placenta (77.3%). A total of 11.7% of cases with placental detection had no HBV DNA detection in the maternal blood, indicating that the placenta could be a site of HBV accumulation. Of the 31 HBV-positive blood samples detected by nested PCR, the detected strains were subgenotype C1 (77.4%), subgenotype B9 (9.7%), and subgenotype C2, B2, B4, and recombinant B4/C2 (3.2% for each). Genotype B had a trend in increased risk of placental HBV DNA detection compared to genotype C, with a relative risk of 1.40 (95% CI: 1.07-1.84). No specific point mutation had a significant effect on HBV DNA detection in placental tissue. Mutation of C454T tended to enhance HBV DNA detection in placental tissue, whereas T400A tended to have a lower detection rate. No mutation was detected in different sample types collected from the same cases. Conclusions: HBV DNA detection in the fetus was identified in approximately 25% of HBV-positive mothers, associated with the presence of HBV in the placenta in most cases. The placenta could possibly be a site of HBV accumulation. Subgenotype C1 was the most common subgenotype, followed by subgenotype B9. HBV genotype B possibly had a higher trend in intrauterine detection than HBV genotype C. Mutation is unlikely to occur during intrauterine exposure.

Bulevirtide and emerging drugs for the treatment of hepatitis D

INTRODUCTION

Hepatitis delta virus (HDV) causes acute and chronic liver disease that requires the co-infection of the Hepatitis B virus and can lead to significant morbidity and mortality. Bulevirtide is a recently introduced entry inhibitor drug that acts on the sodium taurocholate cotransporting peptide, thereby preventing viral entry to target cells in chronic HDV infection. The mainstay of chronic HDV therapy prior to bulevirtide was interferon alpha, which has an undesirable side effect profile.

AREAS COVERED

We review bulevirtide data from recent clinical trials in Europe and the United States. Challenges to development and implementation of bulevirtide are discussed. Additionally, we review ongoing trials of emerging drugs for HDV, such as pegylated interferon lambda and lonafarnib.

EXPERT OPINION

Bulevirtide represents a major shift in treatment for chronic HDV, for which there is significant unmet need. Trials that compared bulevirtide in combination with interferon alpha vs interferon alpha monotherapy demonstrated significant increase in virologic response. Overall, treatment with different doses of bulevirtide were comparable. Bulevirtide was generally well tolerated, and no serious adverse events occurred. Understanding the true prevalence of HDV, as well as continued studies of emerging drugs will prove valuable to the larger goal of eradication of Hepatitis D.

Hepatitis B and Hepatitis D Viruses: A Comprehensive Update with an Immunological Focus

Hepatitis B virus (HBV) and hepatitis delta virus (HDV) are highly prevalent viruses estimated to infect approximately 300 million people and 12-72 million people worldwide, respectively. HDV requires the HBV envelope to establish a successful infection. Concurrent infection with HBV and HDV can result in more severe disease outcomes than infection with HBV alone. These viruses can cause significant hepatic disease, including cirrhosis, fulminant hepatitis, and hepatocellular carcinoma, and represent a significant cause of global mortality. Therefore, a thorough understanding of these viruses and the immune response they generate is essential to enhance disease management. This review includes an overview of the HBV and HDV viruses, including life cycle, structure, natural course of infection, and histopathology. A discussion of the interplay between HDV RNA and HBV DNA during chronic infection is also included. It then discusses characteristics of the immune response with a focus on reactions to the antigenic hepatitis B surface antigen, including small, middle, and large surface antigens. This paper also reviews characteristics of the immune response to the hepatitis D antigen (including small and large antigens), the only protein expressed by hepatitis D. Lastly, we conclude with a discussion of recent therapeutic advances pertaining to these viruses.

The altered HLA-DQ expression in peripheral blood T cells of chronic hepatitis B patients characterizes the function of T cells

OBJECTIVE

This study aimed to clarify the expression of HLA-DQ and granulysin in peripheral blood T-cell subsets in patients with chronic hepatitis B virus (CHB) and to evaluate their significance in assisting CHB diagnosis and immune status assessment.

METHODS

Peripheral blood from 34 CHB patients, 36 inactive HBsAg carriers and 33 healthy controls were collected, and HLA-DQ and granulysin in a series of T-cell subsets were analysed by flow cytometry. The ability to secrete IL-10 and IFN-γ and the functional T-cell subsets were measured in Treg and CD4 cells expressing HLA-DQ or not. Correlation analyses were further conducted between HLA-DQ/granulysin-related subsets and clinical indicators of HBV infection, and ROC curves were built to evaluate diagnosis efficiency of HLA-DQ-related subsets.

RESULTS

HLA-DQ+ percentages in circulating CD4 T cells were downregulated in CHB patients. The proportions of HLA-DQ + Tfh in CHB were upregulated while HLA-DQ+ percentages in Treg were decreased. In terms of function, the IFN-γ secretion ability of CD4 + T cells and IL-10 secretion in Tregs were stronger in HLA-DQ+ than HLA-DQ- subsets. HLA-DQ + CD4 + T cells and HLA-DQ + Treg were negatively correlated with HBV-DNA, while HLA-DQ + Tfh and Tfc cells were positively correlated with HBV-DNA and ALT. HLA-DQ + Treg/Tfh/Tfc could help to distinguish CHB from inactive HBsAg carriers.

CONCLUSION

HLA-DQ on T cells can characterize the function of T-cell subsets and analysis of HLA-DQ can help to evaluate immune status and assist in diagnosis of CHB.

Hepatitis B virus reactivation in rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by proliferative synovitis, which can cause cartilage and bone damage as well as functional limitations. Disease-modifying anti-rheumatic drugs have significantly improved the prognosis of RA patients. However, people with RA, when combined with hepatitis B virus (HBV) infection, may experience reactivation of HBV during treatment with anti-rheumatic drugs. The outcome of HBV reactivation (HBVr) varies from liver inflammation to liver failure, while insufficient HBV screening in RA patients has been reported in various countries. Therefore, it is necessary to identify patients at high risk before starting immunosuppressive therapy. The immune response plays an important role in anti-HBV infection. However, most anti-rheumatic drugs exert an inhibitory effect on the body's immune system, resulting in HBVr. Therefore, it is necessary to conduct a comprehensive evaluation based on host factors, viral factors, and drug factors. In this paper, we summarize the mechanism of HBVr, the risk of HBVr caused by anti-rheumatic drugs, and the appropriate diagnosis and treatment process for RA patients so that clinicians can have a more comprehensive understanding of HBVr in RA patients.

Advancements in the prevention of hepatitis B recurrence by nucleos(t)ide analogue monotherapies after liver transplantation

Previous studies have shown that the recurrence rate of HBV (hepatitis B virus) after liver transplantation (LT) can be as high as 80% without any preventive measures. Therefore, prevention of HBV recurrence after LT is always an essential part of clinical work worldwide. The NAs that have been approved for HBV treatment include lamivudine, adefovir dipivoxil, entecavir (ETV), and telbivudine, tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide (TAF). They are often combined with HBIG to prevent HBV recurrence after LT clinically. However, NAs with a higher genetic barrier, such as ETV, TDF, and TAF, can improve liver function by strongly inhibiting HBV replication and reducing the risks of HBV resistance. Recently, some NAs with a higher genetic barrier, such as ETV, TDF, and TAF, have been adopted as monotherapy for preventing the recurrence of hepatitis B after LT in multiple organ transplant centres and have achieved effective outcomes. This article aims to review the advances for NAs monotherapy in prophylaxis for HBV recurrence after LT.

HBV/HIV Coinfection: Impact on the Development and Clinical Treatment of Liver Diseases

Hepatitis B virus (HBV) infection is a common contributor to chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma. Approximately 10% of people with human immunodeficiency virus (HIV) also have chronic HBV co-infection, owing to shared transmission routes. HIV/HBV coinfection accelerates the progression of chronic HBV to cirrhosis, end-stage liver disease, or hepatocellular carcinoma compared to chronic HBV mono-infection. HBV/HIV coinfection alters the natural history of hepatitis B and renders the antiviral treatment more complex. In this report, we conducted a critical review on the epidemiology, natural history, and pathogenesis of liver diseases related to HBV/HIV coinfection. We summarized the novel therapeutic options for these coinfected patients.

Brief Report: Heplisav-B Seroprotection in People With HIV: A Single-Center Experience

BACKGROUND

Heplisav-B, a hepatitis B virus (HBV) vaccine with an immunostimulatory adjuvant, was FDA approved in 2017 for adults ≥18 years. In randomized controlled trials, Heplisav-B demonstrated seroprotection rates (SPR) of 90%-95% versus 65%-80% for Engerix-B. No studies have included people with HIV (PWH), and the SPR and its predictors in this population are unknown.

SETTING

Quaternary care center HIV clinic.

METHODS

This retrospective cohort study evaluated PWH aged ≥18 years without current HBV seroprotection (anti-HBV surface antibody level [anti-HBs] <10 mIU/mL) who were administered Heplisav-B. Patients without post-immunization titers were excluded. The primary outcome was the SPR, the proportion of participants with HBV seroprotection at any point after the first vaccination.

RESULTS

Among 64 PWH included, median time to anti-HBs measurement after vaccination was 13 weeks. The median age was 58 years, 81% were men, and 95% had a viral load <200. The SPR was 81% in the entire cohort (and 86% in those without significant non-HIV immunosuppression), 79% in those with no prior HBV vaccination and no anti-HBc positivity, and 84% in those with prior vaccine nonresponse. Lower current and nadir CD4+ counts were associated with progressively lower seroprotection.

CONCLUSION

In the first single-center retrospective study of Heplisav-B in PWH, the SPR compared favorably with the SPR seen among PWH from prior HBV vaccines across key subgroups. Given these findings, Heplisav-B should be considered for expanded use for HBV vaccination in PWH. Further research on the effectiveness of a repeat vaccination series or higher dosing in nonresponders is needed.

Efficacy of Nucleotide/Nucleoside Analogues and Hepatitis B Immunoglobulin Therapy in Blocking Mother-to-Child Transmission of Hepatitis B in an Eastern Chinese Group

The objective of this study was to investigate the efficacy and potential side-effects of nucleotide/nucleoside analogues and hepatitis B immunoglobulin injection of newborns in blocking mother-to-child transmission of hepatitis B virus in the middle and late pregnancy period. 238 cases of enrolled pregnant women were divided into the Telbivudine group, the Tenofovir group, the Lamivudine group, and the hepatitis B immunoglobulin (HBIG) group. Enrolled patients received corresponding therapies. Clinical and laboratory data were collected. Results showed that the levels of HBV DNA of the enrolled pregnant women in the Telbivudine, Tenofovir, and Lamivudine groups decreased rapidly after 12 weeks of drug intervention compared with those in the control. HBsAg positive rate in newborns and in children 24 weeks after birth was 0/60, 0/60, 0/60, 3/30, and 11/28 in the Telbivudine, Tenofovir, Lamivudine, HBIG, and control groups, respectively. No significant side-effects were identified after following up to 12 months after birth. Our results show that routine HBV vaccine plus HBIG injections is insufficient in blocking mother-to-child HBV transmission. Administration of nucleotide/nucleoside analogues or HBIG at pregnancy is suggested to maximize the blocking of vertical HBV transmission.

Prevalence of Chronic Hepatitis B Virus Infection in the United States

Chronic hepatitis B virus (HBV) infection represents a major global health problem, affecting an estimated 257-291 million persons worldwide and is associated with substantial morbidity and mortality because of clinical complications, such as liver cirrhosis and hepatocellular carcinoma. Despite existing resources for vaccination, screening, and treatment, the burden of chronic HBV remains significant within the United States (US). Both the World Health Organization (WHO) and US Department of Health and Human Services (DHHS) have articulated formal hepatitis elimination plans, although an updated assessment of the epidemiology and prevalence of chronic HBV is needed to inform these initiatives. The Chronic Liver Disease Foundation (CLDF), a nonprofit 501(c)(3) educational organization dedicated to raising awareness of liver disease, partnered with a panel of leading US hepatologists to conduct an updated literature review to develop a contemporary HBV prevalence range estimate. Panel members researched and evaluated the peer-reviewed literature on HBV prevalence and, in May 2019, discussed their findings during a live HBV epidemiology workshop. The panel proposed an overall estimated prevalence for chronic HBV infection in the US of 1.59 million persons (range 1.25-2.49 million). This review provides a summary of the workshop findings and conclusions, which may serve to inform future initiatives focused on HBV screening and prevention in the US.

Approach to women who become pregnant while on tenofovir disoproxil fumarate for chronic B hepatitis: A report of two cases

Mother-to-child transmission of hepatitis B virus can occur during the intrauterine, antenatal and postnatal periods, with an increased risk of perinatal transmission. Appropriate management of patients who are hepatitis B surface antigen positive during pregnancy can substantially reduce the rates of perinatal transmission. Herein, two pregnant women with chronic hepatitis B are presented; one became pregnant while receiving tenofovir disoproxil fumarate and continued the treatment during pregnancy, the other discontinued tenofovir disoproxil fumarate treatment on her own due to conception, but restarted at 26 weeks of pregnancy. At birth the newborns of both women were vaccinated and immunoglobulin was given, with no perinatal transmission. Whether pregnant women should receive antiviral therapy or immunoprophylaxis still remains controversial. In order to keep the mother's liver stable and to prevent perinatal transmission, it is of paramount importance to manage pregnant women in line with the current information and guidelines.

Present and Future Therapies for Chronic Hepatitis B

Chronic hepatitis B (CHB) remains the leading cause of liver-related morbidity and mortality across the world. If left untreated, approximately one-third of these patients will progress to severe end-stage liver diseases including liver failure, cirrhosis, and hepatocellular carcinoma (HCC). High level of serum HBV DNA is strongly associated with the development of liver failure, cirrhosis, and HCC. Therefore, antiviral therapy is crucial for the clinical management of CHB. Current antiviral drugs including nucleoside/nucleotide analogues (NAs) and interferon-α (IFN-α) can suppress HBV replication and reduce the progression of liver disease, thus improving the long-term outcomes of CHB patients. This chapter will discuss the standard and optimization antiviral therapies in treatment-naïve and treatment-experienced patients, as well as in the special populations. The up-to-date advances in the development of new anti-HBV agents will be also discussed. With the combination of the current antiviral drugs and the newly developed antiviral agents targeting the different steps of the viral life cycle or the newly developed agents modulating the host immune responses, the ultimate eradication of HBV will be achieved in the future.

The antipsychotic medication, risperidone, causes global immunosuppression in healthy mice

Atypical antipsychotic medications such as risperidone are widely prescribed for diverse psychiatric indications including schizophrenia, bipolar disorder and depression. These medications have complex pharmacology and are associated with significant endocrine and metabolic side effects. This class of medications also carries FDA black box warnings due to increased risk of death in elderly patients. Clinical reports indicate that patients treated with these medications are more susceptible to infections; however, the underlying mechanisms/pharmacology are unclear. We have previously reported that risperidone and it’s active metabolite distributes to the bone marrow in clinically relevant concentrations in preclinical species, leading us to hypothesize that the hematopoietic system may be impacted by these medications. To test this hypothesis, using proteomic and cytokine array technology, we evaluated the expression of genes involved in inflammatory and immune function following short term (5 days) and longer term (4 weeks) treatment in healthy animals. We report that low-dose risperidone treatment results in global immunosuppression in mice, observed following 5 days of dosing and exacerbated with longer term drug treatment (4 weeks). These data are consistent with increased susceptibility to infection in patients administered these medications and have profound implications for the increasing off-label prescribing to vulnerable patient populations including children and the elderly.

Hepatitis B virus infection: Prevention of mother-to-child transmission and exacerbation during pregnancy

The aims of this study were to assess the effect of maternal screening for hepatitis B (HB) virus and a perinatal prevention program of mother-to-child transmission, and to identify clinical characteristics and findings associated with HB exacerbation during pregnancy. This prospective cohort study enrolled 3796 pregnant women and their neonates with informed consent. Pregnant women underwent maternal universal screening for HBs antigen (Ag) in the first trimester. If HBs Ag was positive, serum levels of HBe Ag, alanine transaminase (AST), aspartate aminotransferase (ALT), and HB virus (HBV) DNA were measured. All neonates delivered from HBs Ag-positive women were given HB immune globulin and HB vaccine based on the guidelines of the perinatal prevention program. Of the 3796 pregnant women, 40 (1.05%) tested positive for HBs Ag. Three (7.5%) of the 40 HBs Ag-positive women experienced exacerbation of HBV infection during pregnancy. Serum levels of AST (median 776 vs. 22 mIU/ml, p < 0.01), ALT (median 325 vs. 15 mIU/ml, p < 0.01), and HBV-DNA (median 9.1 vs. 5.4 log copies/ml, p < 0.05), and frequencies of HBe Ag-positive (100% vs. 29.7%, p < 0.05) and symptoms of itching or general fatigue (66.7% vs. 0%, p < 0.01) in three women with exacerbation of HBV infection were significantly higher than those in 37 women without exacerbation. There was no case of mother-to-child transmission, suggesting the perinatal HBV prevention program was effective. Levels of HBe Ag, liver enzymes, and HBV-DNA as well as symptoms of itching and general fatigue should be carefully monitored for HBs Ag-positive women during pregnancy and the postpartum period.

The As and Bs of HIV and Hepatitis Co-Infection

Hepatitis A and B co-infection among people living with HIV are public health challenges that account for an increasing degree of morbidity and mortality. Understanding the changing epidemiology, clinical manifestations, and new approaches to treatment and prevention continues to be important in the care of people living with HIV. We conducted a review of the literature that included studies on hepatitis A and HIV co-infection and hepatitis B and HIV co-infection, focusing on epidemiology, clinical manifestations, treatment, and prevention. Important updates include the changing epidemiology of hepatitis A outbreaks among the homeless and individuals who use substances, and novel approaches to hepatitis B vaccination and hepatitis B cure strategies.

Management of Hepatitis B Virus Infection: 2018 Guidelines from the Canadian Association for the Study of Liver Disease and Association of Medical Microbiology and Infectious Disease Canada

Hepatitis B virus (HBV) infection is an important public health problem in Canada. In keeping with evolving evidence and understanding of HBV pathogenesis, the Canadian Association for the Study of Liver Disease periodically publishes HBV management guidelines. The goals of the 2018 guidelines are to (1) highlight the public health impact of HBV infection in Canada and the need to improve diagnosis and linkage to care, (2) recommend current best-practice guidelines for treatment of HBV, (3) summarize the key HBV laboratory diagnostic tests, and (4) review evidence on HBV management in special patient populations and include more detail on management of HBV in pediatric populations. An overview of novel HBV tests and therapies for HBV in development is provided to highlight the recent advances in HBV clinical research. The aim and scope of these guidelines are to serve as an up-to-date, comprehensive resource for Canadian health care providers in the management of HBV infection.

Current evidence on the management of hepatitis B in pregnancy

Hepatitis B virus (HBV) infection is one of the main public health problems across the globe, since almost one third of the world population presents serological markers of contact with the virus. A profound impact on the epidemiology has been exerted by universal vaccination programmes in many countries, nevertheless the infection is still widespread also in its active form. In the areas of high endemicity (prevalence of hepatitis B surface antigen positivity > 7%), mother-to-child transmission represents the main modality of infection spread. That makes the correct management of HBV in pregnancy a matter of utmost importance. Furthermore, the infection in pregnancy needs to be carefully assessed and handled not only with respect to the risk of vertical transmission but also with respect to gravid women health. Each therapeutic or preventive choice deserves to be weighed upon attentively. On many aspects evidence is scarce or controversial. This review will highlight the latest insights into the paramount steps in managing HBV in pregnancy, with particular attention to recommendations from recent guidelines and data from up-do-date research syntheses.

Management of chronic hepatitis B during pregnancy

Chronic hepatitis B is globally prevalent and is a major cause of cirrhosis and hepatocellular carcinoma. Despite immunoprophylaxis against hepatitis B in pregnancy, perinatal transmission still occurs in at least 10% of the children born to a mother with high level of viremia. Decisions regarding hepatitis B therapy during pregnancy must take into account the benefits and safety for both the mother and the unborn baby. In this review, we summarize the current treatment options for chronic hepatitis B with a focus on management during pregnancy and the evidence-based strategies to prevent vertical transmission of hepatitis B virus (HBV).

Hepatitis B virus infection

Hepatitis B virus (HBV) is a hepatotropic virus that can establish a persistent and chronic infection in humans through immune anergy. Currently, 3.5% of the global population is chronically infected with HBV, although the incidence of HBV infections is decreasing owing to vaccination and, to a lesser extent, the use of antiviral therapy to reduce the viral load of chronically infected individuals. The course of chronic HBV infection typically comprises different clinical phases, each of which potentially lasts for decades. Well-defined and verified serum and liver biopsy diagnostic markers enable the assessment of disease severity, viral replication status, patient risk stratification and treatment decisions. Current therapy includes antiviral agents that directly act on viral replication and immunomodulators, such as interferon therapy. Antiviral agents for HBV include reverse transcriptase inhibitors, which are nucleoside or nucleotide analogues that can profoundly suppress HBV replication but require long-term maintenance therapy. Novel compounds are being actively investigated to achieve the goal of HBV surface antigen seroclearance (functional cure), a serological state that is associated with a higher remission rate (thus, no viral rebound) after treatment cessation and a lower rate of cirrhosis and hepatocellular carcinoma. This Primer addresses several aspects of HBV infection, including epidemiology, immune pathophysiology, diagnosis, prevention and management.

Pharmacokinetic properties of a novel inosine analog, 4'-cyano-2'-deoxyinosine, after oral administration in rats

4′-cyano-2′-deoxyinosine (SK14-061a), a novel nucleoside analog based on inosine, has antiviral activity against the human immunodeficiency virus type 1 that has the ability to acquire resistance against many types of reverse transcriptase inhibitors based on nucleosides. The aim of this study was to investigate the pharmacokinetics studies after its oral administration to rats. For this purpose, we first developed and validated an analytical method for quantitatively determining SK14-061a levels in biological samples by a UPLC system interfaced with a TOF-MS system. A rapid, simple and selective method for the quantification of SK14-061a in biological samples was established using liquid chromatography mass spectrometry (LC-MS) with solid phase extraction. The pharmacokinetic properties of SK14-061a in rats after oral administration were then evaluated using this LC-MS method. SK14-061a was found to be relatively highly bioavailable, is rapidly absorbed from the intestinal tract, and is then mainly distributed to the liver and then ultimately excreted via the urine in an unchanged form. Furthermore, the simultaneous administration of SK14-061a with the nucleoside analog, entecavir, led to a significant alteration in the pharmacokinetics of SK14-061a. These results suggest that the SK14-061a has favorable pharmacokinetic properties with a high bioavailability with the potential for use in oral pharmaceutical formulations, but drug-drug interactions should also be considered.