Mechanism and clinical application of thymosin in the treatment of lung cancer

Cancer is one of the leading causes of death worldwide. The burden of cancer on public health is becoming more widely acknowledged. Lung cancer has one of the highest incidence and mortality rates of all cancers. The prevalence of early screening, the emergence of targeted therapy, and the development of immunotherapy have all significantly improved the overall prognosis of lung cancer patients. The current state of affairs, however, is not encouraging, and there are issues like poor treatment outcomes for some patients and extremely poor prognoses for those with advanced lung cancer. Because of their potent immunomodulatory capabilities, thymosin drugs are frequently used in the treatment of tumors. The effectiveness of thymosin drugs in the treatment of lung cancer has been demonstrated in numerous studies, which amply demonstrates the potential and future of thymosin drugs for the treatment of lung cancer. The clinical research on thymosin peptide drugs in lung cancer and the basic research on the mechanism of thymosin drugs in anti-lung cancer are both systematically summarized and analyzed in this paper, along with future research directions.

Effect of Thymalfasin (Thymosin-α-1) on Reversing Lymphocytopenia among Patients with COVID-19

Introduction

Thymosin-α-1 (Tα1) elevates lymphocyte counts among patients with COVID-19, but its effect on reversing lymphocytopenia is unknown.

Methods

24 patients treated with Tα1 and 100 patients in the control arm were included in this analysis. The incidence rate of reversing lymphocytopenia, overall and stratified by baseline oxygen support, above the threshold for classification of lymphocytopenia (i.e., Total Lymphocyte Count (TLC) < 1.5 x 10⁹/L) and severe lymphocytopenia (i.e., TLC < 1.0 x 10⁹/L) within 3, 5, and 7 days of treatment initiation was calculated, along with incidence rate ratios (IRRs) and 95% confidence intervals (CIs).

Results

Compared with the standard of care, the rate of reversing lymphocytopenia (IRR: 2.38, 95% CI: 0.92 – 5.81) and severe lymphocytopenia (IRR: 1.57, 95% CI: 0.59 – 3.72), especially among patients with severe lymphocytopenia on high flow oxygen support (IRR: 3.64, 95% CI: 0.71 – 23.44), was greater for patients treated with Tα1 within 3 days of treatment initiation, although analyses were not significant.

Conclusion

Among patients with hypoxemia and lymphocytopenia, Tα1 may reverse lymphocytopenia and severe lymphocytopenia, particularly within 3 days of treatment initiation, faster than the standard of care.

A Pilot Trial of Thymalfasin (Thymosin-α-1) to Treat Hospitalized Patients With Hypoxemia and Lymphocytopenia Due to Coronavirus Disease 2019 Infection

BACKGROUND

Thymosin-α-1 (Tα1) may be a treatment option for coronavirus disease 2019 (COVID-19), but efficacy and safety data remain limited.

METHODS

Prospective, open-label, randomized trial assessing preliminary efficacy and safety of thymalfasin (synthetic form of Tα1), compared with the standard of care, among hospitalized patients with hypoxemia and lymphocytopenia due to COVID-19.

RESULTS

A total of 49 patients were included in this analysis. Compared with control patients, the incidence of clinical recovery was higher for treated patients with either baseline low-flow oxygen (subdistribution hazard ratio, 1.48 [95% confidence interval, .68-3.25]) or baseline high-flow oxygen (1.28 [.35-4.63]), although neither difference was significant. Among patients with baseline low-flow oxygen, treated patients, compared with control patients, had an average difference of 3.84 times more CD4+ T cells on day 5 than on day 1 (P = .01). Nine serious adverse events among treated patients were deemed not related to Tα1.

CONCLUSIONS

Tα1 increases CD4+ T-cell count among patients with baseline low-flow oxygen support faster than the standard of care and may have a role in the management of hospitalized patients with hypoxemia and lymphocytopenia due to COVID-19.

CLINICAL TRIALS REGISTRATION

NCT04487444.

CD3+, CD4+, and CD8+ Expression in Cells in Peripheral Blood of Silicosis Patients and Intervention Effect of Thymalfasin

OBJECTIVE

This study aims to investigate the changes in CD3⁺, CD4⁺ and CD8⁺ expression in cells in peripheral blood of silicosis patients, and observe the immunoregulatory effect of thymalfasin.

METHODS

A total of 80 silicosis patients were enrolled in the study, randomly divided into two groups: treatment group and control group (n=40, each group). In addition, 40 healthy adults, who underwent physical examinations in our hospital, were enrolled into the health examination group. Patients in the control group and treatment group were given anti-infection treatment, according to their conditions. Patients in the treatment group additionally received thymalfasin. Then, the number of peripheral blood T lymphocyte subsets in subjects in all three groups before and after treatment was measured.

RESULTS

(1) Before treatment, CD3⁺, CD4⁺ and CD8⁺ levels in cells were significantly lower in the treatment group and control group than in the health examination group, and the differences were statistically significant (P<0.05). (2) In the treatment group, the number of CD4⁺ cells in peripheral blood was significantly higher after one week of treatment, when compared to that before treatment, and the difference was statistically significant (P<0.05).

CONCLUSION

In silicosis patients, CD3⁺, CD4⁺ and CD8⁺ cells in peripheral blood are decreased, and thymalfasin can significantly increase CD4⁺ cells in peripheral blood of silicosis patients.

Thymalfasin, a promising adjuvant therapy in small hepatocellular carcinoma after liver resection

There is limited information available concerning the effect of thymalfasin (Tα1) as an adjuvant therapy in hepatocellular carcinoma (HCC) patient who received liver resection. The present study aimed to evaluate whether Tα1 can improve the prognosis of small HCC patients after liver resection.A total of 206 patients with small HCC who underwent liver resection were analyzed in our retrospective cohort study. Patients were divided into 2 groups: group A (resection + Tα1, n = 44) and group B (resection, n = 162). Clinical data, overall survival (OS), and recurrence-free survival (RFS) were compared. Prognostic factors were identified using multivariate analysis.After a median follow-up of 47.0 months, 134 patients (65%) had recurrence, and 62 patients (30.09%) died. The 1, 3, and 5-year OS rate of patients in group A was 97.7%, 90.6%, and 82.9%, respectively, and 95.1%, 80.5%, and 62.9%, respectively, for patients in group B (P = .014). The 1, 3, and 5-year RFS rate of patients in group A was 70.5%, 56.8%, and 53.3%, respectively, and 65.8%, 41.3%, and 32.1%, respectively, for patients in group B (P = .015). Multivariate analysis indicated that Tα1 was an independent prognostic factor for both OS (P = .015, hazard ratio 0.349, 95% confidence interval 0.149-0.816) and RFS (P = .019, hazard ratio 0.564, 95% confidence interval 0.349-0.910).Tα1 as an adjuvant therapy after liver resection may improve the prognosis of small HCC patients after liver resection.

Evaluation of thymosin α 1 in nonclinical models of the immune-suppressing indications melanoma and sepsis

OBJECTIVES

Recent understanding of the complex pathophysiology of melanoma and severe sepsis suggests that immune-modulating compounds such as thymosin alpha 1 (INN: thymalfasin; abbreviated Ta1) could be useful in the treatment of these two unrelated immune-suppressing indications.

RESEARCH DESIGN AND METHODS

Three nonclinical murine models were utilized, including: i) a lung metastasis B16 model; ii) a B16-based tumor growth model; and iii) a cecal-ligation and puncture (CLP) sepsis model.

RESULTS

In the lung metastasis model, Ta1 treatment alone led to a 32% decrease in metastases (p < 0.05). Additionally, combinations of Ta1 and an anti-PD-1 antibody led to significantly fewer metastases than vehicle. In the tumor growth model, significant decreases in tumor growth were seen: 34% (p = 0.015) to 46% (p = 0.001) depending on the Ta1 dose. In the CLP sepsis model, Ta1 treatment showed a positive trend towards increased survival and decreased bacterial load. In this CLP model, Ta1 also appeared to have an effect on the levels of some biomarkers.

CONCLUSIONS

All three models demonstrated a benefit after treatment with Ta1, with no evidence of toxicity. These initial pilot studies support the hypothesis that immune-suppressive indications, including sepsis and melanoma, may be treated with Ta1 alone or by Ta1 in combination with other immunotherapies.