Efficacy of thymosin α1 in management of radiation pneumonitis in patients with locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy: A Phase 2 Clinical Trial (GASTO-1043)

PURPOSE

To evaluate the efficacy of thymosin α1 in management of radiation pneumonitis (RP) in patients with locally advanced non-small cell lung cancer (LANSCLC) treated with concurrent chemoradiotherapy (CCRT).

METHODS AND MATERIALS

This phase II, single-arm trial enrolled patients with unresectable LANSCLC of 18 to 75 years' old and an Eastern Cooperative Oncology Group performance status of 0 to 1. Eligible patients received definitive CCRT and weekly thymosin α1 from the start of CCRT till 2 months after CCRT. Patients were administered 51 Gy in 17 daily fractions or 40 Gy in 10 daily fractions in the first course followed by a re-evaluation and those patients without disease progression had an adaptive plan of 15 Gy in 5 daily fractions or 24 Gy in 6 daily fractions as a boost. Concurrent chemotherapy consisted of weekly docetaxel (25 mg/m²) and nedaplatin (25 mg/m²) during radiation therapy. The primary endpoint was the incidence of Grade (G) ≥2 RP. Secondary endpoints included the incidence of late pulmonary fibrosis, total lymphocyte count (TLC), serum C-reactive protein (CRP) levels, and the composition of gut microbiota. TLC and CRP data were collected at baseline, 2-3 weeks during CCRT, the end of CCRT, 2 and 6 months after CCRT. Fecal samples were collected at baseline and the end of CCRT. Patients treated with CCRT but without thymosin α1 intervention during the same period were selected as the control group by the propensity score matching method.

RESULTS

Sixty-nine patients were enrolled in the study, and another 69 patients were selected as the control group. The incidence of G≥2 RP was lower in the study group compared with control cases (36.2% vs 53.6%, P=0.040). G1 late pulmonary fibrosis occurred in 2 (3.7%) patients of the control group compared with no event in the study group (P=0.243). Compared with the control group, the incidence of G3-4 lymphopenia (19.1% vs. 62.1%, P<0.001) was lower, and the median TLC nadir (0.51 k/µL vs. 0.30 k/µL, P<0.001) was higher in the study group. The proportion of patients with maximum CRP≥100 mg/L was lower in the study group (13.8% vs. 29.7% P=0.029). The diversity and community composition of the gut microbiota were not significantly different between the two groups.

CONCLUSIONS

Administration of thymosin α1 during and after CCRT was associated with significant reductions in G≥2 RP and G3-4 lymphopenia in patients with LANSCLC compared to historic controls.

Innovative Therapies Targeting the Virus and the Host for Treating Chronic Hepatitis B Virus Infection: From Bench to Bedside

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. Accordingly, several drugs with antiviral properties have been used to treat CHB patients during the last four decades. However, the treatment outcome is not satisfactory because viral suppression is not usually related to the containment of progressive liver damage. Although proper reconstruction of host immunity is essential in CHB patients, as of today, there is no acceptable immune therapeutic protocol for them. These realities have exposed new, novel, and innovative therapeutic regimens for the management of CHB patients. This review will update the scope and limitation of the different innovative antiviral and immune therapeutic approaches for restoring effective host immunity and containing the virus in CHB patients to block progression to LC and HCC.

Immune therapies against chronic hepatitis B

Patients with chronic hepatitis B (CHB) represent a living and permanent reservoir of hepatitis B virus (HBV). Millions of these CHB patients will eventually develop complications such as liver cirrhosis, hepatic failure, and hepatocellular carcinoma if they are not treated properly. Accordingly, several antiviral drugs have been developed for the treatment of CHB, but these drugs can neither eradicate all forms of HBV nor contain the progression of complications in most patients with CHB. Thus, the development of new and novel therapeutics for CHB remains a pressing need. The molecular and cellular mechanisms underlying the pathogenesis of CHB indicate that immune dysregulations may be responsible for HBV persistence and progressive liver damage in CHB. This provided the scientific and ethical basis for the immune therapy of CHB patients. Around 30 years have passed since the initiation of immune therapies for CHB in the early 1990s, and hundreds of clinical trials have been accomplished to substantiate this immune treatment. Despite these approaches, an acceptable regimen of immune therapy is yet to be realized. However, most immune therapeutic agents are safe for human usage, and many of these protocols have inspired considerable optimism. In this review, the pros and cons of different immune therapies, observed in patients with CHB during the last 30 years, will be discussed to derive insights into the development of an evidence-based, effective, and patient-friendly regimen of immune therapy for the treatment of CHB.

Thymus Gland: A Double Edge Sword for Coronaviruses

The thymus is the main lymphoid organ that regulates the immune and endocrine systems by controlling thymic cell proliferation and differentiation. The gland is a primary lymphoid organ responsible for generating mature T cells into CD4+ or CD8+ single-positive (SP) T cells, contributing to cellular immunity. Regarding humoral immunity, the thymic plasma cells almost exclusively secrete IgG1 and IgG3, the two main complement-fixing effector IgG subclasses. Deformity in the thymus can lead to inflammatory diseases. Hassall’s corpuscles’ epithelial lining produces thymic stromal lymphopoietin, which induces differentiation of CDs thymocytes into regulatory T cells within the thymus medulla. Thymic B lymphocytes produce immunoglobulins and immunoregulating hormones, including thymosin. Modulation in T cell and naive T cells decrement due to thymus deformity induce alteration in the secretion of various inflammatory factors, resulting in multiple diseases. Influenza virus activates thymic CD4+ CD8+ thymocytes and a large amount of IFNγ. IFNs limit virus spread, enhance macrophages’ phagocytosis, and promote the natural killer cell restriction activity against infected cells. Th2 lymphocytes-produced cytokine IL-4 can bind to antiviral INFγ, decreasing the cell susceptibility and downregulating viral receptors. COVID-19 epitopes (S, M, and N proteins) with ≥90% identity to the SARS-CoV sequence have been predicted. These epitopes trigger immunity for antibodies production. Boosting the immune system by improving thymus function can be a therapeutic strategy for preventing virus-related diseases. This review aims to summarize the endocrine-immunoregulatory functions of the thymus and the underlying mechanisms in the prevention of COVID-19.

Thymosins in multiple sclerosis and its experimental models: moving from basic to clinical application

BACKGROUND

Multiple sclerosis (MS) afflicts more than 2.5 million individuals worldwide and this number is increasing over time. Within the past years, a great number of disease-modifying treatments have emerged; however, efficacious treatments and a cure for MS await discovery. Thymosins, soluble hormone-like peptides produced by the thymus gland, can mediate immune and non-immune physiological processes and have gained interest in recent years as therapeutics in inflammatory and autoimmune diseases.

METHODS

Pubmed was searched with no time constraints for articles using a combination of the keywords "thymosin/s" or "thymus factor/s" AND "multiple sclerosis", mesh terms with no language restriction.

RESULTS

Here, we review the state-of-the-art on the effects of thymosins on MS and its experimental models. In particular, we describe what is known in this field on the roles of thymosin-α1 (Tα1) and -β4 (Tβ4) as potential anti-inflammatory as well as neuroprotective and remyelinating molecules and their mechanisms of action.

CONCLUSION

Based on the data that Tα1 and Tβ4 act as anti-inflammatory molecules and as inducers of myelin repair and neuronal protection, respectively, a possible therapeutic application in MS for Tα1 and Tβ4 alone or combined with other approved drugs may be envisaged. This approach is reasonable in light of the current clinical usage of Tα1 and data demonstrating the safety, tolerability and efficacy of Tβ4 in clinical practice.

Effect of a C-end rule modification on antitumor activity of thymosin α1

Thymosin α1 (Tα1), a hormone containing 28 amino acids, has been approved in several cancer therapies, but the lack of tumor-targeting hinders its full use in tumor treatment. We designed a new peptide by connecting Tα1 and RGDR, generating a product, Tα1-RGDR, where RGDR is located in the C-end with both tumor-homing and cell internalizing properties (C-end rule peptides, a consensus R/KXXR/K motif). This work aimed to study the antitumor and immunological activities of Tα1-RGDR, and its differences compared with the wild-type Tα1. The antitumor and immunological activities of Tα1-RGDR were measured using the B16F10 tumor and immunologic suppression models. Tα1-RGDR treatment led to significant inhibition of tumor growth at a dose at which Tα1 showed a slight effect in the B16F10 tumor growth model. In the immunologic suppression model, Tα1-RGDR shared almost equivalent immunomodulatory effect with Tα1. These results demonstrated the better therapeutic effects after treatment with Tα1-RGDR compared with Tα1. Moreover, both Tα1-RGDR and Tα1 shared a helical conformation in the presence of trifluoroethanol based on CD spectroscopy. Our dock information of Tα1-RGDR when combined with integrin αvβ3 or neuropilin-1 further confirmed previous experimental results. All these findings suggest that Tα1-RGDR might be a useful therapy for tumors by overcoming its wild type limitation of tumor homing.

Immunomodulatory and enhanced antitumor activity of a modified thymosin α1 in melanoma and lung cancer

Tumor-targeted therapy is an attractive strategy for cancer treatment. Peptide hormone thymosin α1 (Tα1) has been used against several diseases, including cancer, but its activity is pleiotropic. Herein, we designed a fusion protein Tα1-iRGD by introducing the tumor homing peptide iRGD to Tα1. Results show that Tα1-iRGD can promote T-cell activation and CD86 expression, thereby exerting better effect and stronger inhibitory against melanoma and lung cancer, respectively, than Tα1 in vivo. These effects are indicated by the reduced densities of tumor vessels and Tα1-iRGD accumulation in tumors. Moreover, compared with Tα1, Tα1-iRGD can attach more B16F10 and H460 cells and exhibits significantly better immunomodulatory activity in immunosuppression models induced by hydrocortisone. Circular dichroism spectroscopy and structural analysis results revealed that Tα1 and Tα1-iRGD both adopted a helical confirmation in the presence of trifluoroethanol, indicating the structural basis of their functions. These findings highlight the vital function of Tα1-iRGD in tumor-targeted therapy and suggest that Tα1-iRGD is a better antitumor drug than Tα1.

Immunotherapy for hepatitis B in the direct acting antiviral era: Reevaluating the thymosin α1 efficacy trials in the light of a combination therapy approach

Hepatitis B virus (HBV) causes both acute and chronic hepatitis and infects large numbers of individuals worldwide. Unfortunately, prediction of typical clinical outcome is problematic and there is considerable variability in the frequency, duration and severity of disease progression. The mainstay of HBV treatment is directed towards the suppression of HBV replication by nucleos(t)ide analogs (NUCs). The use of immunomodulators such as α-Interferon and thymosin α1 can, in select patients, results in elimination of both HBsAg and HBeAg. Given the observation that viral clearance is most effective in the presence of a strong immune response, this review summarizes data suggesting that the use of a combination of an immune modulator such as Tα1 with a highly effective NUC may result in a more successful therapeutic approach in patients with chronic hepatitis B (CHB). Results from small studies using combination Tα1 and NUCs are encouraging, and ongoing clinical trials combining entecavir with Tα1 are anticipated to provide important data assessing the use of a combination of Tα1 with a NUC to achieve resolution of CHB.

Thymosin α1 Interacts with Hyaluronic Acid Electrostatically by Its Terminal Sequence LKEKK

Thymosin α1 (Tα1), is a peptidic hormone, whose immune regulatory properties have been demonstrated both in vitro and in vivo and approved in different countries for treatment of several viral infections and cancers. Tα1 assumes a conformation in negative membranes upon insertion into the phosphatidylserine exposure as found in several pathologies and in apoptosis. These findings are in agreement with the pleiotropy of Tα1, which targets both normal and tumor cells, interacting with multiple cellular components, and have generated renewed interest in the topic. Hyaluronan (HA) occurs ubiquitously in the extracellular matrix and on cell surfaces and has been related to a variety of diseases, and developmental and physiological processes. Proteins binding HA, among them CD44 and the Receptor for HA-mediated motility (RHAMM) receptors, mediate its biological effects. NMR spectroscopy indicated preliminarily that an interaction of Tα1 with HA occurs specifically around lysine residues of the sequence LKEKK of Tα1 and is suggestive of a possible interference of Tα1 in the binding of HA with CD44 and RHAMM. Further studies are needed to deepen these observations because Tα1 is known to potentiate the T-cell immunity and anti-tumor effect. The binding inhibitory activity of Tα1 on HA-CD44 or HA-RHAMM interactions can suppress both T-cell reactivity and tumor progression.

Thymosin α1 therapy subsequent to radical hepatectomy in patients with hepatitis B virus-associated hepatocellular carcinoma: A retrospective controlled study

The clinical efficacy of thymosin α1 (Tα1) therapy in patients with hepatocellular carcinoma (HCC) subsequent to radical hepatectomy is unclear. In the present study, the impact of Tα1 therapy on outcomes in HCC patients after radical hepatectomy was retrospectively evaluated. Medical records were retrospectively reviewed for 146 patients with hepatitis B virus (HBV)-associated HCC who were treated by radical hepatectomy and subsequently with Tα1 therapy, as well as for 412 control patients with HBV-associated HCC treated by radical hepatectomy. Propensity score matching was used to minimize confounding variables due to baseline differences. Liver function, recurrence-free survival and overall survival rates were compared between the two groups. Serum markers of liver function were significantly improved in the Tα1 group compared with the control group. The 1-, 2- and 3-year overall survival rates were 87.2, 82.0 and 68.4% in the Tα1 group and 78.2, 64.2 and 49.7% in the control group (P=0.011). The 1-, 2- and 3-year recurrence-free survival rates were 79.7, 70.8 and 67.3% in the Tα1 group and 69.9, 61.5 and 51.6% in the control group (P=0.019). The results suggested that post-hepatectomy Tα1 therapy improves liver function and significantly prolong recurrence-free and overall survival in patients with HBV-associated HCC.

Mechanism of Action of Thymosinα1: Does It Interact with Membrane by Recognition of Exposed Phosphatidylserine on Cell Surface? A Structural Approach

Thymosinα1 is a peptidic hormone with pleiotropic activity, which is used in the therapy of several diseases. It is unstructured in water solution and interacts with negative regions of micelles and vesicles assuming two tracts of helical conformation with a structural flexible break in between. The studies of the interaction of Thymosinα1 with micelles of mixed dipalmitoylphosphatidylcholine and sodium dodecylsulfate and vesicles with mixed dipalmitoylphosphatidylcholine/dipalmitoylphosphatidylserine, the latter the negative component of the membranes, by (1)H and natural abundance (15)N NMR are herewith reported, reviewed, and discussed. The results indicate that the preferred interactions are those where the surface is negatively charged due to sodium dodecylsulfate or due to the presence of dipalmitoylphosphatidylserine exposed on the surface. In fact the unbalance of dipalmitoylphosphatidylserine on the cellular surface is an important phenomenon present in pathological conditions of cells. Moreover, the direct interaction of Thymosinα1 with K562 cells presenting an overexposure of phosphatidylserine as a consequence of resveratrol-induced apoptosis was carried out.

Historical review of thymosin α 1 in infectious diseases

INTRODUCTION

Thymosin α 1 (Tα1) is a peptidic biological response modifier, which plays a significant role in activating and regulating various cells of the immune system. For the above-mentioned activities it is expected to exert a clinical benefit in the treatment of diseases where the immune system is altered.

AREAS COVERED

Several clinical trials have been carried out with Tα1 for treatment or prevention of many different infectious diseases such as hepatitis B and C, sepsis and Aspergillosis in bone marrow-transplanted patients. Data available on the use of Tα1 in infectious disease as well as a vaccine enhancer will be reviewed to possibly generate new working hypothesis.

EXPERT OPINION

Tα1 has been widely used in thousands of patients. Nevertheless, there are some issues that have not yet been properly addressed (i.e., dose, schedule, combination treatments, end-points to be evaluated in clinical trials). In the most recent clinical trials Tα1 has been used at higher doses than those commonly used in the past showing a direct proportionality between the dose and the effect. The safety profile of Tα1 is excellent and it is virtually devoid of toxicity.

Management of chronic hepatitis B infection: Current treatment guidelines, challenges, and new developments

Chronic hepatitis B (CHB) virus infection is a global public health problem, affecting more than 400 million people worldwide. The clinical spectrum is wide, ranging from a subclinical inactive carrier state, to progressive chronic hepatitis, cirrhosis, decompensation, and hepatocellular carcinoma. However, complications of hepatitis B virus (HBV)-related chronic liver disease may be reduced by viral suppression. Current international guidelines recommend first-line treatment of CHB infection with pegylated interferon, entecavir, or tenofovir, but the optimal treatment for an individual patient is controversial. The indications for treatment are contentious, and increasing evidence suggests that HBV genotyping, as well as serial on-treatment measurements of hepatitis B surface antigen and HBV DNA kinetics should be used to predict antiviral treatment response. The likelihood of achieving a sustained virological response is also increased by extending treatment duration, and using combination therapy. Hence the paradigm for treatment of CHB is constantly evolving. This article summarizes the different indications for treatment, and systematically reviews the evidence for the efficacy of various antiviral agents. It further discusses the shortcomings of current guidelines, use of rescue therapy in drug-resistant strains of HBV, and highlights the promising clinical trials for emerging therapies in the pipeline. This concise overview presents an updated practical approach to guide the clinical management of CHB.

Efficacy of thymosin α-1 plus peginterferon α-2a combination therapy compared with peginterferon α-2a monotherapy in HBeAg-positive chronic hepatitis B: a prospective, multicenter, randomized, open-label study

OBJECTIVE

Thymosin α-1 plus interferon α-2a offers superior efficacy over interferon α-2a alone in patients with chronic hepatitis B. The aim was to compare the antiviral efficacy of thymosin α-1 plus peginterferon α-2a and peginterferon α-2a alone in HBeAg-positive chronic hepatitis B patients.

MATERIALS AND METHODS

HBeAg-positive CHB patients were enrolled in this prospective, randomized, open-label study. Fifty-one patients were assigned to either combination (26 patients; 180 μg of peginterferon α-2a weekly for 48 weeks and 1.6 mg of thymosin α-1 twice a week for the first 12 weeks) or monotherapy (25 patients; 180 μg of peginterferon α-2a weekly for 48 weeks) groups.

RESULTS

The rates of the combined response, defined as HBeAg seroconversion, HBV DNA suppression, and normalization of serum ALT, were 4/26 (15.4%) and 3/25 (12.0%) for the combination group and the monotherapy group at the end of treatment (p = 0.725), and 6/26 (23.1%) and 5/25 (20.0%) at the end of follow-up (p = 0.789), respectively. Based on multiple logistic regression analysis, a >2 log₁₀ IU/mL reduction of HBV DNA at week 12 was identified as an independent predictor for combined response (OR, 9.72; 95% CI, 1.33-71.06; p = 0.025) at the end of follow-up. A lower pretreatment HBV DNA level (≤ 7 log(10) IU/mL) was another predictor for combined response (OR, 9.64; 95% CI, 1.23-75.32; p = 0.031). No significant differences in adverse events were observed.

CONCLUSIONS

The short-term addition of thymosin α-1 was not superior to peginterferon α-2a alone in HBeAg-positive CHB patients on the basis of antiviral efficacy.

Immunotherapy for fungal infections

Invasive fungal infections have become a major cause of mortality in immunocompromised individuals. Despite the current availability of number of highly active antifungal agents, overall mortality remains around 40%. Importantly, it is clear that a failure to restore host immunity leads to worse outcomes. These observations provide clear rationale for the development of novel immunotherapies to improve outcomes in immunocompromised individuals with invasive fungal infections. In this article we summarise the key advances that have been made in the field of immunotherapy for fungal infections in recent years, with a particular focus on clinical studies of interferon-γ therapy, adoptive T cell therapy, and gene therapy for chronic granulomatous disorder. In addition a number of pre-clinical approaches are reviewed.

T cell immunopathogenesis and immunotherapeutic strategies for chronic hepatitis B virus infection

Hepatitis B is caused by the host immune response and T cells play a major role in the immunopathogenesis. More importantly, T cells not only destroy hepatocytes infected by hepatitis B virus (HBV), but also control HBV replication or eradicate HBV in a noncytolytic manner. Therefore, analysis of T cell immune response during acute and chronic HBV infection is important to develop a strategy for successful viral control, which could lead to immunotherapy for terminating persistent HBV infection. There have been many attempts at immunotherapy for chronic HBV infection, and some have shown promising results. High viral load has been shown to suppress antiviral immune responses and immunoinhibitory signals have been recently elucidated, therefore, viral suppression by nucleos(t)ide analogs, stimulation of antiviral immune response, and suppression of the immunoinhibitory signals must be combined to achieve desirable antiviral effects.

NMR structure of human thymosin alpha-1. Biochem Biophys Res Commun. 2011;416:356-361. [PMID: 22115779 DOI: 10.1016/j.bbrc.2011.11.041] [Cited by in Crossref: 18] 800 MHz NMR structure of the 28-residue peptide thymosin alpha-1 in 40% TFE/60% water (v/v) has been determined. Restrained molecular dynamic simulations with an explicit solvent box containing 40% TFE/60% TIP3P water (v/v) were used, in order to get the 3D model of the NMR structure. We found that the peptide adopts a structured conformation having two stable regions: an alpha-helix region from residues 14 to 26 and two double β-turns in the N-terminal twelve residues which form a distorted helical structure

800 MHz NMR structure of the 28-residue peptide thymosin alpha-1 in 40% TFE/60% water (v/v) has been determined. Restrained molecular dynamic simulations with an explicit solvent box containing 40% TFE/60% TIP3P water (v/v) were used, in order to get the 3D model of the NMR structure. We found that the peptide adopts a structured conformation having two stable regions: an alpha-helix region from residues 14 to 26 and two double β-turns in the N-terminal twelve residues which form a distorted helical structure.

The treatment of chronic hepatitis B: Focus on adefovir-like antivirals

Several options for the treatment of hepatitis B have been licensed in the last years: interferon, pegylated interferon, lamivudine, adefovir, entecavir, and telbivudine. In addition tenofovir has been licensed in the EU and is expected to be licensed in the USA in 2008. The antivirals can be divided into “lamivudine-like” and “adefovir-like”, which clinically differ in their capacity to induce “YMDD” mutants, which are the hallmark of lamivudine resistance. The differing resistance profile makes them good combination partners, even in the absence of synergy in antiviral potency.

Thymalfasin in the treatment of hepatitis B and C. Ann N Y Acad Sci. 2010;1194:141-146. [PMID: 20536462 DOI: 10.1111/j.1749-6632.2010.05487.x] [Cited by in Crossref: 13] Thymalfasin exhibited an immunomodulatory and a direct antiviral mechanism of action. The low rate of sustained response of chronic hepatitis with current therapies, underscores the need for new therapeutic options. It has been suggested that thymalfasin may have efficacy in the treatment of chronic hepatitis B and C. Pilots studies in patients with chronic hepatitis B treated with thymalfasin in combination with interferon or nucleoside analogue, showed a 70% complete sustained response rate. Studies in chronic hepatitis C patients, would indicate that thymalfasin in combination with standard or pegylated interferon with ribavirin may improve response rate in hepatitis C virus (HCV) naïve and nonresponder patients. However, a large phase-III randomized study conducted in Europe in HCV patients nonresponder to Peg-interferon with ribavirin, demonstrated that thymalfasin did not improve the rate of sustained virologic responses, but, in patients who completed therapy, thymalfasin significantly diminished the relapse rate. In conclusion, thymalfasin, in combination with the standard of care, may be helpful as an adjuvant in the treatment of patients with chronic hepatitis B and C

Thymalfasin exhibited an immunomodulatory and a direct antiviral mechanism of action. The low rate of sustained response of chronic hepatitis with current therapies, underscores the need for new therapeutic options. It has been suggested that thymalfasin may have efficacy in the treatment of chronic hepatitis B and C. Pilots studies in patients with chronic hepatitis B treated with thymalfasin in combination with interferon or nucleoside analogue, showed a 70% complete sustained response rate. Studies in chronic hepatitis C patients, would indicate that thymalfasin in combination with standard or pegylated interferon with ribavirin may improve response rate in hepatitis C virus (HCV) naïve and nonresponder patients. However, a large phase-III randomized study conducted in Europe in HCV patients nonresponder to Peg-interferon with ribavirin, demonstrated that thymalfasin did not improve the rate of sustained virologic responses, but, in patients who completed therapy, thymalfasin significantly diminished the relapse rate. In conclusion, thymalfasin, in combination with the standard of care, may be helpful as an adjuvant in the treatment of patients with chronic hepatitis B and C.

[Treatment of hepatitis B: new perspectives]

Despite the development of new anitiviral agents, the treatment of chronic hepatitis B remains a major clinical challenge. Major achievements have been made with the rationale use of antivirals exhibiting a complementary cross resistance profile to prevent antiviral drug resistance. The current concept of modern antiviral therapy of chronic hepatitis B relies on a precise virologic monitoring and early treatment adaptation to prevent drug resistance. The difficulty of achieving viral clearance and the risk of drug resistance development are major arguments to continue research in the field of antivirals and to identify new targets for therapy. The development of true combination therapy is highly desirable to fulfil the objective of long-term viral suppression, clearance of viral cccDNA and infected cells and ultimately cure of the disease.

A randomized controlled trial of thymalfasin plus transarterial chemoembolization for unresectable hepatocellular carcinoma

PURPOSE

Patients with advanced hepatocellular carcinoma (HCC) have few treatment options. Thymalfasin (thymosin α-1) is an immunomodulator that may increase response to ablative therapy through direct anti-tumor action or enhanced protection against infections. We compared transarterial chemoembolization (TACE) plus thymalfasin with TACE alone for unresectable HCC.

METHODS

In this phase II, randomized trial, 25 patients received either TACE plus thymalfasin (1.6 mg SC, 5 times weekly; n = 14) or TACE alone (n = 11) for 24 weeks. Response was defined as transition to transplant eligibility or lack of disease progression through week 72. Survival was assessed through 24 months post-treatment.

RESULTS

Eight of fourteen (57.1%) patients in the TACE + thymalfasin group versus 5 of 11 (45.5%) patients in the TACE-only group became responders (P = 1.0). Four of fourteen TACE + thymalfasin patients versus none of 11 TACE-only patients became eligible for transplant. Median overall survival time was 110.3 weeks for the TACE + thymalfasin group versus 57.0 weeks for the TACE-only group (P = 0.45). Seven patients in each group experienced serious adverse events; there were no bacterial infections in the TACE + thymalfasin group versus 4 in the TACE-only group. There were 3 deaths in the TACE + thymalfasin group and 5 in the TACE-only group.

CONCLUSIONS

In patients with unresectable HCC, TACE + thymalfasin resulted in numerically higher rates of survival and tumor response, including transplant candidacy, with fewer bacterial infections, than TACE alone. Treatment regimens for HCC including thymalfasin as an immunomodulator should be evaluated in larger trials.

Comparison of the efficacy of thymosin alpha-1 and interferon alpha in the treatment of chronic hepatitis B: a meta-analysis

Chronic hepatitis B virus (HBV) infection is a serious problem because of its worldwide distribution and possible adverse sequelae, such as cirrhosis and hepatocellular carcinoma. Thymosin alpha-1 (Talpha1) is an immune modifier that has been shown to be effective for chronic hepatitis B (CHB) in some trials. But the trials comparing Talpha1 vs. interferon alpha (IFNalpha) treatment in CHB have been small and the results have been inconsistent. So we conducted a meta-analysis to compare the efficacy of Talpha1 and IFNalpha in the treatment of CHB. Generally, four randomized controlled trials including 199 CHB patients who received Talpha1 or IFNalpha treatment were identified through MEDLINE and EMBASE online search. Virological (for hepatitis B e antigen (HBeAg) positive patients, loss of HBV DNA and HBeAg; for HBeAg negative patients, loss of HBV DNA), biochemical (normalization of transaminases) and complete responses (fulfill criteria of biochemical and virological response simultaneously) were analyzed using the intention-to-treat method. The odds ratio (OR) was used to measure the magnitude of the efficacy. The ORs (95% confidence interval) of the virological response, biochemical response and complete response of Talpha1 over IFNalpha at the end of 6 months treatment were 0.62 (0.35, 1.10), 0.60 (0.34, 1.05) and 0.54 (0.30, 0.97), respectively. The ORs (95% confidence interval) of the virological response, biochemical response and complete response of Talpha1 over IFNalpha at the end of follow-up (6 months post-treatment) were 3.71 (2.05, 6.71), 3.12 (1.74, 5.62) and 2.69 (1.47, 4.91), respectively. These data showed that compared with IFNalpha, the benefit of Talpha1 was not immediately significant at the end of therapy, but virological, biochemical and complete response had a tendency to increase or accumulate gradually after the therapy. For three of the four trials that studied HBeAg-negative patients, the results are mostly applicable to HBeAg-negative CHB.