Evaluation of the efficacy and safety of a precise thymalfasin-regulated PRaG regimen for advanced refractory solid tumours: protocol for the open-label, prospective, multicentre study (PRaG5.0 study).

INTRODUCTION: The PRaG regimen, which consists of hypofractionated radiotherapy combined with a programmed cell death-1/programmed cell death ligand-1 (PD-1/PD-L1) inhibitor and granulocyte-macrophage colony stimulating factor (GM-CSF), has been demonstrated to have a survival benefit in patients with advanced solid tumours who have failed at least two lines of treatment. Nonetheless, lymphopenia poses an impediment to the enduring efficacy of PD-1/PD-L1 inhibitor therapy. Adequate lymphocyte reserves are essential for the efficacy of immunotherapy. Coupling the PRaG regimen with immunomodulatory agents that augment the number and functionality of lymphocytes may yield further survival benefits in this cohort of patients. OBJECTIVE: The aim of this study is to investigate the effectiveness and safety of a meticulously thymalfasin-controlled PRaG regimen in patients with advanced and chemotherapy-resistant solid tumours. METHODS AND ANALYSIS: The study has a prospective, single-arm, open-label, multicentre design and aims to recruit up to 60 patients with histologically confirmed advanced solid tumours that have relapsed or metastasised. All eligible patients will receive a minimum of two cycles of the PRaG regimen comprising thymalfasin followed by maintenance treatment with a PD-1/PD-L1 inhibitor and thymalfasin for 1 year or until disease progression. Patients will be monitored according to the predetermined protocol for a year or until disease progression after initiation of radiotherapy. ETHICS AND DISSEMINATION: The study protocol was approved by the Ethics Committee of the Second Affiliated Hospital of Soochow University, on 25 November 2022 (JD-LK-2022-151-01) and all other participating hospitals. Findings will be disseminated through national and international conferences. We also plan to publish our findings in high-impact peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT05790447.

Enhanced Immunomodulatory Effects of Thymosin-Alpha-1 in Combination with Polyanionic Carbosilane Dendrimers against HCMV Infection.

Resistance and toxicity associated with current treatments for human cytomegalovirus (HCMV) infection highlight the need for alternatives and immunotherapy has emerged as a promising strategy. This study examined the in vitro immunological effects of co-administration of Thymosin-alpha-1 (Tα1) and polyanionic carbosilane dendrimers (PCDs) on peripheral blood mononuclear cells (PBMCs) during HCMV infection. The biocompatibility of PCDs was assessed via MTT and LDH assays. PBMCs were pre-treated with the co-administered compounds and then exposed to HCMV for 48 h. Morphological alterations in PBMCs were observed using optical microscopy and total dendritic cells (tDCs), myeloid dendritic cells (mDCs), and plasmacytoid dendritic cells (pDCs), along with CD4+/CD8+ T cells and regulatory T cells (Treg), and were characterized using multiparametric flow cytometry. The findings revealed that Tα1 + PCDs treatments increased DC activation and maturation. Furthermore, increased co-receptor expression, intracellular IFNγ production in T cells and elevated Treg functionality and reduced senescence were evident with Tα1 + G2-S24P treatment. Conversely, reduced co-receptor expression, intracellular cytokine production in T cells, lower functionality and higher senescence in Treg were observed with Tα1 + G2S16 treatment. In summary, Tα1 + PCDs treatments demonstrate synergistic effects during early HCMV infection, suggesting their use as an alternative therapeutic for preventing virus infection.

Comprehensive Review of the Safety and Efficacy of Thymosin Alpha 1 in Human Clinical Trials.

Objective: This study aims to assess the safety and efficacy of Thymosin Alpha 1 (Tα1) through a comprehensive narrative review of clinical studies involving over 11 000 human subjects in more than 30 trials. The focus was on Tα1's application in COVID-19, autoimmune conditions, and cancer treatment, with implications for future considerations. Methods: We systematically searched articles relevant to critical studies on COVID-19, infectious diseases, cancer, and autoimmune diseases indexed on Pubmed, Google Scholar, and Cochrane Library. Our focus was on evaluating the safety and efficacy of Tα1 in human subjects. Clinical trials conducted worldwide involving diverse populations were analyzed to assess the safety and effectiveness of Tα1. The review examines explicit outcomes in over 11 000 human subjects, emphasizing its role in addressing COVID-19, autoimmune conditions, and cancer treatment. Results: Contrary to the FDA's restriction on Tα1 and 21 additional peptides in 2023, our analysis reveals consistent evidence of Tα1's safety and efficacy. The peptide has demonstrated significant effectiveness in treating various conditions, including COVID-19, autoimmune disorders, and cancer. This review summarizes conclusions drawn from a comprehensive examination of clinical trials worldwide. Conclusions: Based on substantial evidence from clinical trials, Tα1 emerges as a well-tolerated and effective immune modulator. The FDA>s restriction appears unfounded, as Tα1 has shown safety and efficacy beyond the initially specified conditions. Urgent attention and intervention are warranted to ensure the continued availability of this life-saving peptide through prescription. Therefore, it is recommended that the FDA permits 503A compounding pharmacies to compound Tα1, considering its potential to treat a variety of conditions effectively.

Role of thymosin α1 in restoring immune response in immunological nonresponders living with HIV.

BACKGROUND: Immunological nonresponders (INRs) living with HIV are at increased risk of co-infection and multiple tumors, with no effective strategy currently available to restore their T-cell immune response. This study aimed to explore the safety and efficacy of thymosin α1 in reconstituting the immune response in INRs. METHODS: INRs with CD4 + T cell counts between 100 and 350 cells/µL were enrolled and received two-staged 1.6 mg thymosin α1 subcutaneous injections for 24 weeks (daily in the first 2 weeks and biweekly in the subsequent 22 weeks) while continuing antiretroviral therapy. T cell counts and subsets, the expression of PD-1 and TIM-3 on T cells, and signal joint T cell receptor excision circles (sjTREC) at week 24 were evaluated as endpoints. RESULTS: Twenty three INRs were screened for eligibility, and 20 received treatment. The majority were male (19/20), with a median age of 48.1 years (interquartile range: 40.5-57.0) and had received antiretroviral therapy for 5.0 (3.0, 7.3) years. Multiple comparisons indicated that CD4 + T cell count and sjTREC increased after initiation of treatment, although no significant differences were observed at week 24 compared to baseline. Greatly, levels of CD4 + T cell proportion (17.2% vs. 29.1%, P < 0.001), naïve CD4 + and CD8 + T cell proportion (17.2% vs. 41.1%, P < 0.001; 13.8% vs. 26.6%, P = 0.008) significantly increased. Meanwhile, the proportion of CD4 + central memory T cells of HIV latent hosts (42.7% vs. 10.3%, P < 0.001) significantly decreased. Moreover, the expression of PD-1 on CD4 + T cells (14.1% vs. 6.5%, P < 0.001) and CD8 + T cells (8.5% vs. 4.1%, P < 0.001) decreased, but the expression of TIM-3 on T cellsremained unaltered at week 24. No severe adverse events were reported and HIV viral loads kept stable throughout the study. CONCLUSIONS: Thymosin α1 enhance CD4 + T cell count and thymic output albeit as a trend rather than an endpoint. Importantly, it improves immunosenescence and decreases immune exhaustion, warranting further investigation. TRIAL REGISTRATION: This single-arm prospective study was registered with ClinicalTrials.gov (NCT04963712) on July 15, 2021.

Immune modulation via dendritic cells by the effect of Thymosin-alpha-1 on immune synapse in HCMV infection.

Tα1 (Thymosin-alpha-1) is a thymus-derived hormone that has been demonstrated to be effective on diverse immune cell subsets. The objective of this study was to determine the in vitro immunomodulatory effect of Tα1 in human cytomegalovirus (HCMV) infection. Dendritic cells (DCs) were isolated from peripheral blood mononuclear cells (PBMCs) by negative selection and cultured in the presence or absence of Tα1. The immunophenotyping of DCs was characterised by multiparametric flow cytometry assessing CD40, CD80, TIM-3 and PDL-1 markers, as well as intracellular TNFα production. Then, autologous CD4+ or CD8+ T-Lymphocytes (TLs) isolated by negative selection from PBMCs were co-cultured with DCs previously treated with Tα1 in the presence or absence of HCMV. Intracellular TNFα, IFNγ, IL-2 production, CD40-L and PD-1 expression were assessed through immunophenotyping, and polyfunctionality in total TLs and memory subsets were evaluated. The results showed that Tα1 increased CD40, CD80, TIM-3 and TNFα intracellular production while decreasing PDL-1 expression, particularly on plasmacytoid dendritic cells (pDCs). Therefore, Tα1 modulated the production of TNFα, IFNγ and IL-2 in both total and memory subsets of CD4+ and CD8+ TLs by upregulating CD40/CD40-L and downregulating PDL-1/PD-1 expression. Our study concludes that Tα1 enhances antigen-presenting capacity of DCs, improves TLs responses to HCMV infection, and enhances the polyfunctionality of CD8+ TLs. Consequently, Tα1 could be an alternative adjuvant for use in therapeutic cell therapy for immunocompromised patients.

The efficacy of thymosin alpha-1 therapy in moderate to critical COVID-19 patients: a systematic review, meta-analysis, and meta-regression.

BACKGROUND: Effort to search for the optimal COVID-19 treatment has continuously been attempted. Thymosin alpha-1 have immunomodulatory properties which may be beneficial in case of viral infection. This study's goal is to determine whether thymosin alpha-1 is effective in treating people with moderate-to-severe COVID-19. METHODS: We searched for literature in 4 database: Scopus, Europe PMC, Medline, ClinicalTrials.gov, and Cochrane Library until March 25th, 2023. If those articles have data on the efficacy of thymosin alpha-1 therapy on COVID-19, they would be included. Risk ratio (RR) and Mean Difference (MD) along with their 95% confidence intervals were used to pool the results of dichotomous and continuous variables, respectively. RESULTS: Pooled data from 8 studies indicated that moderate to critical Covid-19 patients who were receiving thymosin alpha-1 therapy had significantly lower mortality from COVID-19 (RR 0.59; 95% CI 0.37-0.93, p = 0.02, I2 = 84%), but without any difference in the needs for mechanical ventilation (RR 0.83; 95% CI 0.48-1.44, p = 0.51, I2 = 74%) and hospital length of stay (MD 2.32; 95% CI - 0.93, 5.58, p = 0.16, I2 = 94%) compared to placebo. The benefits of thymosin alpha-1 on the mortality rate were significantly affected only by sample size (p = 0.0000) and sex (p = 0.0117). CONCLUSION: Our study suggests that treatment with thymosin alpha-1 may reduce mortality rate in moderate to critical COVID-19 patients. Randomized clinical trials (RCTs) are still required to verify the findings of our study.

Risk Factors and Drug Efficacy for Severe Illness in Hemodialysis Patients Infected with the Omicron Variant of COVID-19.

INTRODUCTION: The Omicron variant of the novel coronavirus (COVID-19) has been spreading more rapidly and is more infectious, posing a higher risk of death and treatment difficulty for patients undergoing hemodialysis. This study aims to explore the severity rate and risk factors for hemodialysis patients infected with the Omicron variant and to conduct a preliminary analysis of the clinical efficacy of drugs. METHODS: Clinical and biochemical indicators of 219 hemodialysis patients infected with the Omicron variant were statistically analyzed. The patients were divided into two groups based on whether they were severely ill or not, and multiple regression analysis was conducted to determine the risk factors for severe illness. The severely ill patients were then grouped based on discharge or death, and the treatment drugs were included as influencing factors for multiple regression analysis to determine the risk factors and protective factors for death of severely ill patients, and drug efficacy analysis was conducted. RESULTS: Analysis showed that diabetes, low oxygen saturation, and high C-reactive protein (CRP) were independent risk factors for severe illness in hemodialysis patients infected with the Omicron variant. A history of diabetes and high C-reactive significantly increased the risk of severe illness in patients (aOR: 1.450; aOR: 1.011), while a high oxygen saturation level can reduce this risk (aOR: 0.871). In addition, respiratory distress was an independent risk factor for death in severely patients, significantly reducing the probability of discharge for patients (aOR: 0.152). The drugs thymalfasin and Tanreqing significantly increased the probability of discharge for patients (aOR: 1.472; aOR: 3.104), with the latter having a higher correlation, but with a relatively longer effective course. CONCLUSION: Hemodialysis patients infected with the Omicron variant of COVID-19 should pay special attention to their history of diabetes, CRP, and oxygen saturation levels, as well as respiratory distress symptoms, to reduce the risk of severe illness and death. In addition, thymalfasin and Tanreqing may be considered in treatment.

Thymosin α1 modulated the immune landscape of COVID-19 patients revealed by single-cell RNA and TCR sequencing.

BACKGROUND: The Coronavirus disease-19 (COVID-19) pandemic has posed a serious threat to global health. Thymosin α1 (Tα1) was considered to be applied in COVID-19 therapy. However, the data remains limited. METHODS: Participants with or without Tα1 treatment were recruited. Single cell RNA-sequencing (scRNA-seq) and T cell receptor-sequencing (TCR-seq) of the peripheral blood mononuclear cell (PBMC) samples were done to analyze immune features. The differential expression analysis and functional enrichment analysis were performed to explore the mechanism of Tα1 therapy. RESULTS: 33 symptomatic SARS-CoV-2-infected individuals (COV) and 11 healthy controls (HC) were enrolled in this study. The proportion of CD3+ KLRD1+ NKT, TBX21+ CD8+ NKT was observed to increase in COVID-19 patients with Tα1 treatment (COVT) than those without Tα1 (COV) (p = 0.024; p = 0.010). These two clusters were also significantly higher in Health controls with Tα1 treatment (HCT) than those without Tα1 (HC) (p = 0.016; p = 0.031). Besides, a series of genes and pathways related to immune responses were significantly higher enriched in Tα1 groups TBX21+ CD8+ NKT, such as KLRB1, PRF1, natural killer cell-mediated cytotoxicity pathway, chemokine signaling pathway, JAK-STAT signaling pathway. The increased TRBV9-TRBJ1-1 pair existed in both HCs and COVID-19 patients after Tα1 treatment. 1389 common complementarity determining region 3 nucleotides (CDR 3 nt) were found in COV and HC, while 0 CDR 3 nt was common in COVT and HCT. CONCLUSIONS: Tα1 increased CD3+ KLRD1+ NKT, TBX21+ CD8+ NKT cell proportion and stimulated the diversity of TCR clones in COVT and HCT. And Tα1 could regulate the expression of genes associated with NKT activation or cytotoxicity to promote NKT cells. These data support the use of Tα1 in COVID-19 patients.

Zoledronic acid and thymosin α1 elicit antitumor immunity against prostate cancer by enhancing tumor inflammation and cytotoxic T cells.

BACKGROUND: Advanced or metastatic prostate cancer (PCa) is still an incurable malignancy with high lethality and a poor prognosis. Despite the remarkable success of immunotherapy against many types of cancer, most patients with PCa receive minimal benefit from current immunotherapeutic strategies, because PCa is an immune cold tumor with scarce T-cell infiltration in the tumor microenvironment. The aim of this study was to develop an effective immunotherapeutic approach for immune cold PCa tumors. METHODS: The therapeutic efficacy of androgen deprivation therapy (ADT) and zoledronic acid (ZA) plus thymosin α1 (Tα1) therapy was analyzed retrospectively in patients with advanced or metastatic PCa. The effects and mechanisms by which ZA and Tα1 regulated the immune functions of PCa cells and immune cells were evaluated by a PCa allograft mouse model, flow cytometric analysis, immunohistochemical and immunofluorescence staining assays, and PCR, ELISA, and Western blot analyses. RESULTS: In this study, clinical retrospective analysis revealed that ADT combined with ZA plus Tα1 improved the therapeutic outcomes of patients with PCa, which might be associated with an enhanced frequency of T cells. ZA and Tα1 treatment synergistically inhibited the growth of androgen-independent PCa allograft tumors, with increased infiltration of tumor-specific cytotoxic CD8+ T cells and enhanced tumor inflammation. Functionally, ZA and Tα1 treatment relieved immunosuppression in PCa cells, stimulated pro-inflammatory macrophages, and enhanced the cytotoxic function of T cells. Mechanistically, ZA plus Tα1 therapy blocked the MyD88/NF-κB pathway in PCa cells but activated this signaling in macrophages and T cells, altering the tumor immune landscape to suppress PCa progression. CONCLUSIONS: These findings uncover a previously undefined role for ZA and Tα1 in inhibiting the disease progression of immune cold PCa tumors by enhancing antitumor immunity and pave the way for the application of ZA plus Tα1 therapy as an immunotherapeutic strategy for treating patients with immunologically unresponsive PCa.

Thymosin α1 and Its Role in Viral Infectious Diseases: The Mechanism and Clinical Application.

Thymosin α1 (Tα1) is an immunostimulatory peptide that is commonly used as an immune enhancer in viral infectious diseases such as hepatitis B, hepatitis C, and acquired immune deficiency syndrome (AIDS). Tα1 can influence the functions of immune cells, such as T cells, B cells, macrophages, and natural killer cells, by interacting with various Toll-like receptors (TLRs). Generally, Tα1 can bind to TLR3/4/9 and activate downstream IRF3 and NF-κB signal pathways, thus promoting the proliferation and activation of target immune cells. Moreover, TLR2 and TLR7 are also associated with Tα1. TLR2/NF-κB, TLR2/p38MAPK, or TLR7/MyD88 signaling pathways are activated by Tα1 to promote the production of various cytokines, thereby enhancing the innate and adaptive immune responses. At present, there are many reports on the clinical application and pharmacological research of Tα1, but there is no systematic review to analyze its exact clinical efficacy in these viral infectious diseases via its modulation of immune function. This review offers an overview and discussion of the characteristics of Tα1, its immunomodulatory properties, the molecular mechanisms underlying its therapeutic effects, and its clinical applications in antiviral therapy.

Thymosin α1 interacts with Galectin-1 modulating the ß-galactosides affinity and inducing alteration in the biological activity.

The study of mechanism of action of Thymosin alpha 1 (Tα1) and the basis of the pleiotropic effect in health and disease, is one of the main focus of our ongoing research. Tα1 is a thymic peptide that demonstrates a peculiar ability to restore homeostasis in different physiological and pathological conditions (i.e., infections, cancer, immunodeficiency, vaccination, and aging) acting as multitasking protein depending on the host state of inflammation or immune dysfunction. However, few are the information about mechanisms of action mediated by specific Tα1-target protein interaction that could explain its pleiotropic effect. We investigated the interaction of Tα1 with Galectin-1 (Gal-1), a protein belonging to an oligosaccharide binding protein family involved in a variety of biological and pathological processes, including immunoregulation, infections, cancer progression and aggressiveness. Using molecular and cellular methodological approaches, we demonstrated the interaction between these two proteins. Tα1 specifically inhibited the hemagglutination activity of Gal-1, the Gal-1 dependent in vitro formation of endothelial cell tubular structures, and the migration of cancer cells in wound healing assay. Physico-chemical methods revealed the details of the molecular interaction of Tα1 with Gal-1. Hence, the study allowed the identification of the not known until now specific interaction between Tα1 and Gal-1, and unraveled a novel mechanism of action of Tα1 that could support understanding of its pleiotropic activity.

Reduced numbers of naïve CD4 + T cells and an altered CD4/CD8 balance in depressed common variable immune deficiency (CVID) patients. Is thymosin-α1 a possible treatment?

In the 1990's the macrophage-T-cell-theory of depression was posed stating that low grade inflammation and an abnormal T cell system destabilize the development and function of the emotional brain in such a way, that individuals become ultrasensitive to stress. Recently we gathered evidence that indeed higher frequencies of CD4+ memory T cells, lower frequencies of naive CD4 + T cells, higher frequencies of CD8 + T cells (the latter two in part elicited by Cytomegalovirus, CMV, infection) are a characteristic of Major Depressive Disorder (MDD). In MDD patients with a history of childhood trauma and severe depression monocytes are inflammatory activated. Low grade inflammation and T cell system defects have also been reported in patients with Common Variable Immune Deficiency (CVID) (next to antibody production defects). CVID patients show a higher prevalence of mild depression. The aim of this study was to determine T cell frequencies and monocyte inflammatory activation in CVID patients with and without depression. This study confirms that CVID patients have CMV independent decreases in the frequency of naïve CD4 + T cells and it de novo shows a CMV dependent increase in the expression of inflammatory genes in monocytes. CVID patients with depression are additionally characterized by a CMV independent increase in the frequency of naïve CD8 + T cells, while lacking monocyte inflammatory activation. In conclusion, depressed CVID patients have T cell abnormalities comparable to that of patients with regular MDD. These abnormalities are presently targeted by thymosin α1 in an open-label proof of concept trial.

Thymosin alpha 1 - Reimagine its broader applications in the immuno-oncology era.

Thymosin alpha 1 (Tα1) is a highly conserved 28 amino-acid peptide naturally occurring in the thymus and plays critical roles in T cell maturity and differentiation. Its synthetic form, thymalfasin, has been approved by various regulatory agencies in the treatment of hepatitis B viral infection and as an enhancer of vaccine response in immune-compromised populations. In China, it has also widely utilized in patients with cancer and severe infections, as well as the emergency use during (Severe Acute Respiratory Syndrome)SARS and COVID-19 pandemic as an immune-regulator. Recent studies showed that Tα1 could significantly improve overall survival (OS) in patients with surgically resectable non-small cell lung cancer (NSCLC) and liver cancers in the adjuvant setting. For patients with locally advanced, unresectable NSCLC, Tα1 could significantly reduce chemoradiation-induced lymphopenia, pneumonia, and trending improvement of OS. Preclinical evidence are emerging to demonstrate that Tα1 may augment efficacy of cancer chemotherapy by reversing efferocytosis-induced M2 polarization of macrophages via activation of a TLR7/SHIP1 axis and enhancing anti-tumor immunity by turning "cold-tumors" to "hot-tumors"; a protective role in reducing colitis caused by immune check-point inhibitors (ICIs). Potential enhancement of ICIs' clinical efficacies has also been indicated. ICIs have transformed ways treating patients with cancer but limitations such as relatively low response rates and certain safety issues remains. Given the roles of Tα1 in regulating cellular immunities and exceptional safety profiles demonstrated in decades clinical uses, we believe that it is plausible to explore implications of Tα1 the immune-oncology setting by combining with ICI-based therapeutic strategies. Background Activities of Tα1. Tα1 is a biological response modifier which activates various cells in the immune system [1-3]. Tα1 is therefore expected to have clinical benefits in disorders where immune responses are impaired or ineffective. These disorders include acute and chronic infections, cancers, and vaccine non-responsiveness. In severe sepsis, for example, sepsis-induced immunosuppression is increasingly recognized as the overriding immune dysfunction in these vulnerable patients [4] and there is now agreement that many patients with severe sepsis survive the first critical hours of the syndrome but eventually die later due to patients' immunosuppression which make the system difficulty to fight the primary bacterial infection, decreased resistance to secondary nosocomial infections, and reactivation of viral infections [5]. Tα1 has been shown to restore immune functions and help to reduce mortality in patients with severe sepsis.

COVID-19 and beyond: Reassessing the role of thymosin alpha1 in lung infections.

The recent COVID-19 pandemic has catalyzed the attention of the scientific community to the long-standing issue of lower respiratory tract infections. The myriad of airborne bacterial, viral and fungal agents to which humans are constantly exposed represents a constant threat to susceptible individuals and bears the potential to reach a catastrophic scale when the ease of inter-individual transmission couples with a severe pathogenicity. While we might be past the threat of COVID-19, the risk of future outbreaks of respiratory infections is tangible and argues for a comprehensive assessment of the pathogenic mechanisms shared by airborne pathogens. On this regard, it is clear that the immune system play a major role in dictating the clinical course of the infection. A balanced immune response is required not only to disarm the pathogens, but also to prevent collateral tissue damage, thus moving at the interface between resistance to infection and tolerance. Thymosin alpha1 (Tα1), an endogenous thymic peptide, is increasingly being recognized for its ability to work as an immunoregulatory molecule able to balance a derailed immune response, working as immune stimulatory or immune suppressive in a context-dependent manner. In this review, we will take advantage from the recent work on the COVID-19 pandemic to reassess the role of Tα1 as a potential therapeutic molecule in lung infections caused by either defective or exaggerated immune responses. The elucidation of the immune regulatory mechanisms of Tα1 might open a new window of opportunity for the clinical translation of this enigmatic molecule and a potential new weapon in our arsenal against lung infections.

A pilot trial of Thymalfasin (Ta1) to prevent covid-19 infection and morbidities in renal dialysis patients: Preliminary report.

PURPOSE: Patients with end-stage renal disease (ESRD) on hemodialysis (HD) are considered particularly susceptible to infection with SARS-CoV2 on the basis of the immunodeficiency associated with advanced age, comorbidity burden, medication use, and need for frequent visits to dialysis clinics. In prior studies, thymalfasin (thymosin alpha 1, Ta1) has been shown to enhance antibody response to influenza vaccine and reduce influenza infection in geriatric populations, including hemodialysis patients, when used as an adjunct to influenza vaccine. Early in the COVID-19 pandemic we speculated that administration of Ta1 to HD patients would result in reduced rate and severity of COVID-19 infection. We also hypothesized that HD patients treated with Ta1 who did become infected with COVID-19 would have a milder course of infection in terms of hospitalization rates, requirement for and length of ICU stays, requirement for mechanical ventilation, and survival. Further, we proposed that patients who avoided COVID-19 infection during the study would have decreased non-COVID-19 infections and hospitalizations compared to controls. PROCEDURES: The study launched in January 2021 and, as of July 1, 2022, 254 ESRD/ HD patients from five dialysis centers in Kansas City, MO have been screened. Of these, 194 patients have been randomized 1:1 to either Group A (1.6 mg Ta1 given subcutaneously twice weekly for 8 weeks), or Group B (control group not receiving Ta1). After the 8-week treatment period, subjects were followed for an additional 4 months and monitored for safety and efficacy. A data safely monitoring board reviewed all reported adverse effects and commented on study progress. RESULTS: To date, only 3 deaths have occurred in subjects treated with Ta1 (Group A), compared to 7 in the control (Group B). There have been 12 COVID-19 related serious adverse effects (SAEs; 5 in Group A, and 7 in Group B). The majority of patients have received a COVID-19 vaccine (91 patients in group A, and 76 patients in Group B) at various times throughout the study. Nearing completion of the study, blood samples have been collected and antibody responses to COVID-19 will be analyzed along with safety and efficacy endpoints when all subjects have completed the study.

Thymosin alpha 1 restores the immune homeostasis in lymphocytes during Post-Acute sequelae of SARS-CoV-2 infection.

The complex alterations of the immune system and the immune-mediated multiorgan injury plays a key role in host response to SARS-CoV-2 infection and in the pathogenesis of COVID-19, being also associated with adverse outcomes. Thymosin alpha 1 (Tα1) is one of the molecules used in the treatment of COVID-19, as it is known to restore the homeostasis of the immune system during infections and cancer. The use of Tα1 in COVID-19 patients had been widely used in China and in COVID-19 patients, it has been shown to decrease hospitalization rate, especially in those with greater disease severity, and reduce mortality by restoring lymphocytopenia and more specifically, depleted T cells. Persistent dysregulation with depletion of naive B and T cell subpopulations and expansion of memory T cells suggest a chronic stimulation of the immune response in individuals with post-acute sequelae of SARS-CoV-2 infection (PASC). Our data obtained from an ex vivo study, showed that in PASC individuals with a chronically altered immune response, Tα1 improve the restoration of an appropriate response, most evident in those with more severe illness and who need respiratory support during acute phase, and in those with specific systemic and psychiatric symptoms of PASC, confirming Tα1 treatment being more effective in compromised patients. The results obtained, along with promising reports on recent trials on Tα1 administration in patients with COVID-19, offer new insights into intervention also for those patients with long-lasting inflammation with post-infectious symptoms, some of which have a delayed onset.

Novel evidence of Thymosin α1 immunomodulatory properties in SARS-CoV-2 infection: Effect on innate inflammatory response in a peripheral blood mononuclear cell-based in vitro model.

The peculiar property of Thymosin alpha 1 (Tα1) to act as master regulator of immune homeostasis has been successfully defined in different physiological and pathological contexts ranging from cancer to infection. Interestingly, recent papers also demonstrated its mitigating effect on the "cytokine storm" as well as on the T-cell exhaustion/activation in SARS-CoV-2 infected individuals. Nevertheless, in spite of the increasing knowledge on Tα1-induced effects on T cell response confirming the distinctive features of this multifaceted peptide, little is known on its effects on innate immunity during SARS-CoV-2 infection. Here, we interrogated peripheral blood mononuclear cell (PBMC) cultures stimulated with SARS-CoV-2 to disclose Tα1 properties on the main cell players of early response to infection, namely monocytes and myeloid dendritic cells (mDC). Moving from ex vivo data showing an enhancement in the frequency of inflammatory monocytes and activated mDC in COVID-19 patients, a PBMC-based experimental setting reproduced in vitro a similar profile with an increased percentage of CD16+ inflammatory monocytes and mDC expressing CD86 and HLA-DR activation markers in response to SARS-CoV-2 stimulation. Interestingly, the treatment of SARS-CoV-2-stimulated PBMC with Tα1 dampened the inflammatory/activation status of both monocytes and mDC by reducing the release of pro-inflammatory mediators, including TNF-α, IL-6 and IL-8, while promoting the production of the anti-inflammatory cytokine IL-10. This study further clarifies the working hypothesis on Tα1 mitigating action on COVID-19 inflammatory condition. Moreover, these evidence shed light on inflammatory pathways and cell types involved in acute SARS-CoV-2 infection and likely targetable by newly immune-regulating therapeutic approaches.

Immunological effects of heated intraperitoneal chemotherapy can be augmented by thymosin α1.

BACKGROUND: Peritoneal metastases of colorectal carcinoma origin (PM-CRC) are treated by cytoreductive surgery and heated intraperitoneal chemotherapy (HIPEC). However, the majority of patients recur, calling for novel treatments. We explored the immunogenic changes induced by HIPEC and the possibility to use thymosin α1 (Tα1) as an immune-stimulatory agent. METHODS: We used an experimental murine model of PM-CRC combined with mitomycin (MMC)-based HIPEC. We determined immune cell infiltration into tumor metastases after HIPEC administration by means of immunohistochemistry, and determined immunogenic cell death signals in tumor cells by real-time polymerase chain reaction. RESULTS: Mice with PM-CRC treated by HIPEC had increased overall survival (OS) compared to sham-treated mice (median OS 22.8 vs 18.9 days, respectively; P < 0.001). HIPEC induced increased infiltration of CD4+, CD8+, CD68 + and CD20 + cells into omental and visceral metastases at a magnitude of 40-100 %. We searched for potential immune signals induced by HIPEC by determining its effects on known immunogenic cell death proteins (heat-shock protein [HSP]-70, HSP-90 and calreticulin). HIPEC significantly increased HSP-90 mRNA expression (2.37 ± 1.5 vs 1-fold change, P < 0.05). The OS of Tα1 treated mice significantly improved compared to HIPEC-treated mice (16.3 ± 0.8 vs 14.1 ± 0.6 days, respectively, P = 0.02) and vs sham (11.8 ± 0.8 days, P = 0.007). CONCLUSIONS: HIPEC induced immunogenic changes that led to increased immune cell infiltration. These changes were further augmented by Tα1 treatment. Future studies aimed at optimizing Tα1 treatment should focus upon the immune response it evokes.

Thymosin α-1 in cancer therapy: Immunoregulation and potential applications.

Thymosin α-1 (Tα-1) is an immunomodulating polypeptide of 28 amino acids, which was the first peptide isolated from thymic tissue and has been widely used for the treatment of viral infections, immunodeficiencies, and especially malignancies. Tα-1 stimulates both innate and adaptive immune responses, and its regulation of innate immune cells and adaptive immune cells varies under different disease conditions. Pleiotropic regulation of immune cells by Tα-1 depends on activation of Toll-like receptors and its downstream signaling pathways in various immune microenvironments. For treatment of malignancies, the combination of Tα-1 and chemotherapy has a strong synergistic effect by enhancing the anti-tumor immune response. On the basis of the pleiotropic effect of Tα-1 on immune cells and the promising results of preclinical studies, Tα-1 may be a favorable immunomodulator to enhance the curative effect and decrease immune-related adverse events of immune checkpoint inhibitors to develop novel cancer therapies.

A randomized controlled pilot trial of etanercept and alpha-1 antitrypsin to improve autologous islet engraftment.

BACKGROUND: In total pancreatectomy with islet auto-transplantation, successful diabetes outcomes are limited by islet loss from the instant blood mediated inflammatory response. We hypothesized that blockade of the inflammatory response with either etanercept or alpha-1-antitrypsin would improve islet function and insulin independence. METHODS: We randomized 43 participants to receive A1AT (90 mg/kg x 6 doses, n = 13), or etanercept (50 mg then 25 mg x 5 doses, n = 14), or standard care (n = 16), aiming to reduce detrimental effects of innate inflammation on early islet survival. Islet graft function was assessed using mixed meal tolerance testing, intravenous glucose tolerance testing, glucose-potentiated arginine-induced insulin secretion studies, HbA1c, and insulin dose 3 months and 1 year post-TPIAT. RESULTS: We observed the most robust acute insulin response (AIRglu) and acute C-peptide response to glucose (ACRglu) at 3 months after TPIAT in the etanercept-treated group (p ≤ 0.02), but no differences in other efficacy measures. The groups did not differ overall at 1 year but when adjusted by sex, there was a trend towards a sex-specific treatment effect in females (AIRglu p = 0.05, ACRglu p = 0.06), with insulin secretion measures highest in A1AT-treated females. CONCLUSION: Our randomized trial supports a potential role for etanercept in optimizing early islet engraftment but it is unclear whether this benefit is sustained. Further studies are needed to evaluate possible sex-specific responses to either treatment. CLINICAL TRIAL NOTATION: This study was performed under an Investigational New Drug Application (IND #119828) from the Food and Drug Administration and was registered on clinicaltrials.gov (NCT#02713997).