Thymosin-α1: evidence for benefits in immunity, neuroprotection, fertility and organ repair

Description of the potential effects of Thymosin alpha 1 based on the literature. (This is not a product description, disclaimer at the bottom of the page)

Thymosin-α1 (Tα1) is a naturally occurring peptide, originally isolated from the thymus gland. It is well known for its role in strengthening the body's immune system. It helps mature immature immune cells, promotes the production and balance of key infection-fighting cells and regulates inflammatory signals that can become overactive in chronic diseases. Importantly, it has received approval in 35 developing countries for the treatment of chronic hepatitis B and C, demonstrating its recognised antiviral and immune-supporting effects.  In addition, Tα1 is widely used as an immune response enhancer in the treatment of other infectious and immune-related diseases, where its safety and immunomodulatory profile make it a valuable therapeutic adjunct. Because the immune system and brain communicate closely with each other, particularly through pathways associated with inflammation, researchers are increasingly interested in whether Tα1 may also have neurological and psychological benefits. Recent findings suggest that Tα1 is an immunomodulatory therapy with benefits that extend far beyond traditional infection- and liver-related applications. Importantly, small-scale human and preclinical studies have shown an association of Tα1 with improved mood symptoms, accompanied by a reduction in inflammatory markers such as interleukin-6 (IL-6) and signs of renewed naïve T-cell production. In addition, Tα1 showed effects on neurodevelopment, including enhancement of hippocampal neurogenesis and cognitive function, as well as neuroprotection after injury and analgesic effects by blocking inflammatory pathways.  Figure. Structure of thymosin-α1 (Tα1) (PubChem [1]) In clinical practice, Tα1 reduced the number of secondary infections and altered the immune response towards recovery in cases of severe acute pancreatitis, improved periodontal healing and long-term tooth survival after " " tooth reimplantation. In addition, it can be safely combined with immune supportive therapies for HIV, where it has shown signs of increased thymus production. In addition, it improves platelet regeneration in immune thrombocytopenia, and early clinical signals suggest potential value in treating cytomegalovirus-associated acute respiratory distress syndrome (CMV/ARDS) after transplantation and in reducing chemotherapy-related nerve damage. In this broad range of applications, Tα1 is most commonly administered in low, intermittent subcutaneous doses or in short daily doses, and its safety profile remains consistently favourable in the available studies.

May help treat depression by reducing inflammation

Thymosin-α1 (Tα1) may help improve mood by alleviating chronic inflammation and promoting immune reconstitution. In a small pilot study, Mersha and colleagues (2025) recruited five people with common variable immunodeficiency (CVID) who also suffered from depression. Participants received injections of Tα1 at a dose of 1.6 mg daily for one week, followed by twice-weekly doses for a further seven weeks. Symptoms of depression decreased significantly: on average, scores fell by 52% compared to a 36% decrease in the comparison group receiving standard treatment. At the same time, the patients' immune systems improved, showing more newly formed healthy immune cells and lower levels of the inflammatory marker IL-6. However, when Tα1 was discontinued, depression returned in the two most severe cases, while the other three patients continued to improve. The immune system benefits also disappeared after discontinuation of the drug [2]. These preliminary results suggest that Tα1 may support mood by restoring immune balance and reducing harmful inflammation, although larger controlled studies are needed to confirm its benefits.

Prevents infection in severe acute pancreatitis

Tα1 can enhance immunity, reduce inflammation and limit life-threatening infections in severe acute pancreatitis (SAP). Tian et al (2025) conducted a systematic review and meta-analysis of five randomised controlled trials involving 706 patients. Compared with standard care alone, Tα1 significantly increased the number of CD4⁺ immune cells (mean difference [MD] = 4.53) and improved the CD4⁺/CD8⁺ ratio (MD = 0.42), indicating better immune regeneration. In addition, lower doses of Tα1 reduced levels of C-reactive protein (CRP; MD = -30.12 mg/l), a key marker of inflammation, while higher doses showed no clear effect on CRP, suggesting a possible dose-response difference in inflammation control. Clinically, Tα1 reduced the number of infections outside the pancreas (risk ratio [RR] = 0.56), including bloodstream infections (RR = 0.60) and abdominal infections (RR = 0.38), although the incidence of lung infections remained unchanged. In addition, severity of illness scores (APACHE II) improved (MD = -1.52), although this did not have a significant impact on the length of hospital stay. Taken together, these findings n , support that Tα1 is an effective immunomodulatory therapy that can help prevent serious infections and improve recovery from SAP [3].

Promotes better healing and survival of teeth

Tα1 appears to improve tissue repair and increase long-term tooth survival after traumatic tooth injury. Loo et al (2008) conducted a double-blind, randomised clinical trial involving 73 patients who required tooth reimplantation after tooth extraction (total loss). Before the reimplantation procedure, patients received Tα1 or saline. Patients treated with Tα1 showed significantly lower levels of inflammatory molecules such as interferon, tumour necrosis factor α (TNF-α) and interleukin-6 (IL-6), and higher white blood cell counts (all p < 0.05). Clinically, they reported better periodontal healing, less abnormal tooth loosening, reduced adhesion (fusion of bone to tooth) and longer overall tooth survival (all p < 0.05). Importantly, this suggests that the short-term ability of Tα1 to modulate immunity and reduce inflammation may translate into better long-term tooth repair and stability after reimplantation [4].

Increases the number of CD4 cells in HIV

Tα1 appears safe for use with immune-enhancing therapies for HIV, but may not further increase CD4 cell counts when added to PEG-IL-2. Ramachandran et al (1996) studied adults with HIV-1 who were treated with zidovudine and had CD4 levels between 50 and 250 cells/µl. Participants received PEG-IL-2 at a dose of 10^6 IU/m² intravenously every fortnight for 20 weeks. After four doses of PEG-IL-2, weekly subcutaneous injections of Tα1 were added, starting at 400 µg/m² and gradually increasing the dose to 1600 µg/m² over two months. As a result, CD4 cell counts increased by approximately 30-40% with PEG-IL-2 alone, but the addition of Tα1 did not further increase CD4 levels. Importantly, viral activity remained under control; PCR assays for proviral DNA, plasma RNA and p24 showed no reactivation. Furthermore, both PEG-IL-2 and Tα1 were well tolerated. These results indicate that, although the combination of these drugs is safe, Tα1 did not provide additional immunological benefit in this short study [5].

Reduces infection in severe acute pancreatitis

Tα1 may help to accelerate immune system recovery and reduce the risk of infection in severe acute pancreatitis (SAP). Wang et al (2011) conducted a double-blind, randomised, controlled clinical trial in which patients with SAP received standard care or Tα1 at a dose of 3.2 mg administered subcutaneously twice daily for seven days. Importantly, Tα1 accelerated the restoration of HLA-DR monocyte expression and improved the CD4/CD8 immune cell ratio on days 8 and 28. Additionally, it reduced the number of positive blood and abdominal cultures, indicating fewer infections. In a n n ew result, patients treated with Tα1 had a shorter stay in the intensive care unit, reflecting faster immune reconstitution and better infection control in early SAP [6].

May increase T-cell production in the thymus in patients with HIV

Tα1 may help the thymus to produce new T cells in HIV patients, even if the overall immune cell count remains unchanged. Chadwick et al (2003) conducted a pilot phase II study involving clinically stable HIV-infected adult patients on HAART with viral titres below 400 copies/ml and CD4 cell counts below 200 cells/µl. Participants were randomly assigned to continue HAART alone or to receive additional Tα1 at a dose of 3.2 mg administered subcutaneously twice weekly for 12 weeks. Importantly, the treatment was well tolerated and no serious side effects were reported. Although the total CD4, CD8 and CD45 cell counts did not increase significantly compared to the control group, the level of sjTREC, a marker of new T-cell production in the thymus, increased in patients receiving Tα1. These results suggest that Tα1 may stimulate thymus-dependent immune regeneration in HIV-infected patients, even if CD4 cell counts in the peripheral blood do not immediately improve [7].

Enhances response to influenza vaccine in older people

Tα1 may help older people overcome age-related immune impairment and respond better to influenza vaccines. Ershler et al (2007) reviewed animal studies and human clinical trials in which Tα1 was administered along with seasonal influenza vaccines to older people, although dosing regimens varied between studies. Importantly, Tα1 increased the seroconversion rate, meaning that more participants developed protective antibodies, and enhanced antibody titres against influenza haemagglutinin antigens. Furthermore, the therapy was well tolerated and no serious safety issues were reported. These results suggest that the addition of Tα1 may counteract immunosenescence and improve the efficacy of the influenza vaccine in the elderly, although larger, well-controlled studies are needed to confirm these benefits [8].

Strengthens immune system regeneration in the case of HIV

Tα1 can increase the number and activity of immune cells in combination with established HIV therapies. Garaci et al (1994) conducted a randomised, open-label 12-month study involving adults with HIV who had CD4 cell counts between 200 and 500 cells/µl. Participants received either zidovudine (AZT) alone, AZT in combination with interferon-α, AZT in combination with Tα1, or triple therapy with AZT, interferon-α and Tα1. Importantly, the triple combination was well tolerated and led to a significant increase in both the number and functional capacity of CD4 T cells compared with AZT alone or any of the dual combinations. It is worth noting that previous laboratory studies have shown that Tα1 and interferon-α can act together to increase lymphocyte-killing activity without interfering with the antiviral effect of AZT, and this immunological synergy was reflected in the clinical trial. Consequently, these results warranted moving to larger double-blind studies to confirm long-term safety and benefit [9].

Improves the ability of sperm to fertilise in men

Tα1 may improve sperm function in men with infertility due to poor sperm yield. Naz et al (1995) conducted a multicentre study involving 68 infertile men. Importantly, Tα1 significantly improved sperm penetration in the hamster oocyte penetration test in 76% participants (50 of 68), with an increase in penetration rate from 31% to 45% (p = 0.0006 to < 0.0001). In addition, the degree of improvement was closely associated with each man's seminal plasma Tα1 level (correlation r = 0.65-0.74; p = 0.039-0.01). This pattern suggests that Tα1 supports key stages of fertilisation, such as capacitation and the acrosomal response. In conclusion, the findings support that Tα1 may be a potential diagnostic or therapeutic agent for male infertility associated with sperm malfunction [10].

Reduces infectious necrosis in acute necrotizing pancreatitis

Tα1 appears to be most effective in preventing infected pancreatic necrosis (IPN) in patients with necrotising pancreatitis who also have hyperglycaemia. Huang et al (2024) conducted a post hoc subgroup analysis of a large, multicentre, randomised controlled trial comparing Tα1 with placebo, focusing on 502 patients. Interestingly, of the 271 patients with high blood sugar, those receiving Tα1 were less likely to have IPN after 90 days than those receiving placebo (18.8% vs 29.7%; risk ratio 0.80, 95% CI 0.37-0.97; p = 0.03). In contrast, Tα1 showed no clear benefit in patients with only high triglyceride levels or in patients with high blood sugar and triglyceride levels. Importantly, the protective effect in hyperglycaemic patients remained stable in multivariate models and several propensity models. These findings suggest that glycaemic status may help identify patients with necrotising pancreatitis who are most likely to benefit from the immune-enhancing effects of Tα1 [11].

Improves response in immune thrombocytopenia

Adding Tα1 to short-term high-dose dexamethasone therapy improves platelet reconstitution and reduces the risk of relapse in patients with newly diagnosed immune thrombocytopenic purpura (ITP). Wang et al (2007) compared 27 patients treated with oral dexamethasone alone at a dose of 40 mg for four days with 39 patients who additionally received Tα1 at a dose of 1.6 mg subcutaneously three times a week for four weeks. Importantly, the combination of these drugs achieved a higher overall response rate (76.9% vs 44.4%, p < 0.05) and a better six-month durable response (61.5% vs 34.6%, p < 0.05). In addition, relapse rates were lower for Tα1 (38.5% vs 65.4%, p < 0.05). Cytokine analysis showed a favourable change in the immune system: IFN-γ and IL-2 levels increased, IL-4 and IL-10 levels decreased, and TGF-β1 levels increased in a positively correlated manner with circulating Tα1 (r = 0.6028, p < 0.05). Taken together, the changes in the immune system indicated a Th1-oriented response and improved tolerance. Importantly, the therapy was well tolerated and no new safety concerns were raised [12].

Improves survival and regeneration of the immune system

Tα1 may improve survival and accelerate immune reconstitution in kidney transplant recipients with life-threatening viral lung complications. Ji et al (2007) studied 46 renal transplant patients who developed cytomegalovirus (CMV) infection and acute respiratory distress syndrome (ARDS). All patients received salvage treatment with antiviral drugs - including gancyclovir at 5 mg/kg intravenously every 12 hours - and appropriate antimicrobial and antifungal therapy. Importantly, participants were randomly allocated to a group receiving thymosin-α1 (Zadaxin) at a dose of 1.6 mg subcutaneously daily or every other day (32 patients) or to a group not receiving Tα1 (14 patients). Interestingly, life-saving efficacy was higher in the Tα1 group (78.1% versus 50%) and mortality was lower (21.9% versus 50%). Furthermore, immune reconstitution was stronger in Tα1: CD4⁺ T-cell counts increased by day 14 and the CD4⁺/CD8⁺ ratio improved. Among survivors, CD4⁺ and CD8⁺ cell counts increased significantly on days 7, 14 and 21 compared with levels at hospital admission. In conclusion, the addition of Tα1 to standard treatment improved survival and accelerated immune reconstitution in this high-risk case of post-transplant CMV-ARDS [13].

Supports immunotherapy and targeted irradiation in tumour control

Tα1 can enhance systemic tumour control when added to immunotherapy and targeted irradiation. Yu and colleagues (2024) described the case of a 48-year-old woman with advanced triple-negative breast cancer and lung metastases who was refractory to previous treatment. The patient received stereotactic body radiotherapy (SBRT), PD-1 checkpoint inhibitor, GM-CSF immune stimulating factor and Tα1. After two cycles of treatment, the main tumour had shrunk by approximately 79% and the three lung metastases had shrunk by almost 57% (partial response according to RECIST v1.1). Blood morphology remained stable without bone marrow suppression and tumour marker (CA-199) decreased. Adverse events were mild and limited to a moderate skin reaction, which resolved with anti-allergic medication. No other serious adverse events were reported. This case suggests that Tα1 may enhance tumour response when used together with PD-1 therapy, GM-CSF and SBRT [14].

Potential to reduce nerve damage associated with chemotherapy

Tα1 may help protect against chemotherapy-induced nerve damage. An et al (2004) evaluated 22 patients with advanced lung or breast cancer who developed moderate to severe nerve damage (grade 2-4) while receiving drugs such as vinorelbine with cisplatin, gemcitabine with cisplatin or paclitaxel with carboplatin or epirubicin. These patients continued chemotherapy, but also received injections of Tα1: 1.6 mg subcutaneously daily for four days before chemotherapy and then 1.6 mg twice weekly for one to three weeks after the start of the cycle. Weekly nerve testing showed that 10 of 22 patients (45.4%) improved from grade 2-4 to below grade 2. These results suggest that Tα1 may have a protective effect on nerves. However, the authors noted that larger, controlled studies are needed to confirm the efficacy and duration of this effect [15].

Results of preclinical studies in animal models

Potential role in early brain development

Tα1 may promote healthy brain growth and protect against early inflammation-related damage. Wang and colleagues (2017) studied newborn mice to understand how Tα1 affects early brain development (no specific dose was given). Mice given Tα1 soon after birth later showed improved learning and memory, as well as a greater number of new nerve cells in the hippocampus, a key memory centre in the brain. In addition, Tα1 restored a healthier balance to the immune system and increased levels of brain growth factors such as BDNF, NGF and IGF-1, which are essential for learning and memory. Importantly, when brain inflammation was experimentally induced, Tα1 preserved the brain's ability to produce new neurons. These findings suggest that Tα1 may help protect the young brain from inflammation and promote normal cognitive development [16].

Influences the communication of brain cells

Tα1 may improve the way brain cells send signals to each other. Yang and colleagues (2003) examined rat brain cells in the laboratory and found that after exposure to Tα1 at concentrations of 1 or 10 micrograms per millilitre, cells sent signals to each other more frequently. Although the strength of each signal remained unchanged, the probability of transmitting a message increased. This therefore points to Tα1 as a potential enhancer of brain activity that can support learning and memory at the cellular level [17].

Protects the brain after blast injury

Tα1 can help the brain to recover from severe trauma by reducing damage and inflammation. Shi and colleagues (2020) tested Tα1 on rats with traumatic brain injury (TBI) caused by an explosion. The animals received injections of Tα1 (200 micrograms per kilogram) twice daily for three days or two weeks. Although early survival improved slightly but not significantly, Tα1 provided clear benefits for cognitive function: rats traversed mazes faster and remembered platform locations better. In addition, it reduced the amount of harmful tau protein associated with long-term brain damage, reduced inflammation and reduced brain swelling. Taken together, these results suggest that Tα1 helps the damaged brain heal by protecting nerve cells and mitigating harmful immune activity [18].

Supporting nerve growth during development

Tα1 and other thymus-derived factors can influence brain development and early learning. Turrini and colleagues (1998) investigated how the thymus, an immune organ, affects the developing brain. Newborn animals that had their thymus removed had lower levels of nerve growth factor (NGF) in their brains, fewer healthy nerve connections and reduced activity of acetylcholine, a brain chemical essential for memory. Interestingly, administration of Tα1 directly to the brain partially remedied these deficits: NGF levels increased, nerve connections improved and acetylcholine production increased. These findings indicate that Tα1 plays an important role in shaping brain development and promoting memory formation early in life [19].

Reduces inflammatory pain (animal studies)

Tα1 can alleviate inflammatory pain by calming the interaction between the immune and nervous systems in the spinal cord. Mersha and colleagues (2020) used a rodent model in which inflammation was induced with complete Freund's adjuvant (CFA). Tα1 decreased both mechanical sensitivity (allodynia) and heat-related pain (hyperalgesia). In addition, interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α) and brain-derived neurotrophic factor (BDNF) levels in the spinal cord decreased, and activation of the Wnt3a/β-catenin pathway, associated with pain signal transduction, was inhibited. Taken together, these results suggest that Tα1 reduces neuroinflammation and pain by restoring healthier immune and neuronal signalling in the spinal cord [20].

Improves survival and reduces organ damage in rats

Tα1 and interferon-α improved survival and reduced organ damage in severe acute pancreatitis. Wang and colleagues (2015) tested a rat model induced with sodium taurocholate and treated the animals with Tα1 (26.7 µg/kg intravenously) or IFN-α (4.0 × 10⁵ U/kg intravenously) after induction. Importantly, both therapies reduced levels of liver and pancreatic damage enzymes (AST, LDH, α-amylase, lipase), reduced levels of the infection marker procalcitonin (PCT) and reduced levels of inflammatory cytokines (TNF-α, IL-4, IL-5, IL-18). In addition, immune reconstitution was stronger: CD3⁺, CD4⁺ and CD8⁺ T-cell levels increased, and the CD4⁺/CD8⁺ ratio improved. Histological studies also showed less pancreatic and lung damage ( ). Importantly, mortality decreased from 50% in untreated rats to 25% in Tα1-treated rats and 33% in IFN-α-treated rats, demonstrating both biochemical and survival benefits [21].

Improves survival and reduces inflammation in the early stages of severe pancreatitis

Tα1 can rebalance the immune response and protect the pancreas in early severe pancreatitis. Yao and colleagues (2007) studied rats with taurocholate-induced disease and administered Tα1 subcutaneously (100 µg/kg) immediately after induction and then again two hours later. Although amylase and lipase were unchanged, inflammatory signals such as IL-1β and TNF-α decreased significantly. In parallel, pancreatic oedema (wet/dry ratio) decreased and T-cell subgroups (CD3⁺, CD4⁺, CD8⁺) reached a healthier balance. In addition, tissue analysis showed less damage to the pancreas. Most importantly, survival at 72 hours was better compared to untreated animals, indicating that Tα1 promotes immune regeneration and early organ protection in severe pancreatitis [22].

Anti-inflammatory and CFTR restoring effects in cystic fibrosis

Tα1 can both reduce airway inflammation and repair abnormal ion transport in cystic fibrosis. Romani and colleagues (2017) studied cystic fibrosis mice and airway cells collected from patients with the common p.Phe508del CFTR mutation. Importantly, Tα1 alleviated persistent airway inflammation and also helped the defective CFTR protein to fold and mature properly, making it more stable and better able to transport chloride across cell membranes. In addition, it combined anti-inflammatory effects with improved ion flow, correcting many tissue problems in both animal and patient-derived cell models. The authors highlighted the high safety of Tα1 in previous immune therapies, suggesting that it could be developed as a single multi-target therapy for the treatment of cystic fibrosis [23].

Improves key sperm functions related to male fertility

Tα1 appears to enhance the ability of sperm to fertilise an egg by improving acrosome function and movement patterns. Naz and colleagues (1992) tested human spermatozoa using penetration assays and detailed movement analyses. Interestingly, synthetic Tα1, but not thymosin-β4, significantly increased sperm penetration (p < 0.001). Interestingly, antibodies against Tα1 or thymosin-β4 also increased penetration by up to 4.7-fold (p < 0.001). These antibodies mainly attached to the acrosome, the enzyme-filled cap that helps sperm enter the egg cell. In addition, both Tα1 and these antibodies enhanced the natural and calcium-induced responses of the acrosome and the release of the fertilising enzyme acrosin. Although overall sperm movement was unchanged, advanced movement characteristics such as velocity, side-to-side head movement and beat frequency were improved, showing stronger hyperactivation . Interestingly, seminal fluid comparisons showed that fertile men had measurable levels of Tα1 and thymosin-β4, while infertile men with sperm dysfunction had significantly lower levels of Tα1 (p = 0.002). These findings suggest that Tα1 helps prepare sperm for fertilisation and may have diagnostic or therapeutic value in the treatment of male infertility [24]. The most effective part of the Tα1 molecule for sperm activity is at its tail end, although full potency requires an intact peptide. Naz and colleagues (1995) compared natural Tα1 with six modified versions that altered the anterior or posterior part of the molecule. Native Tα1 strongly increased sperm penetration (p < 0.0001), with the best effect obtained at a concentration of 0.5 µg per 100 µL. Of the modified forms, only two, Tα1-Gly-NH₂ (with a conserved tail) and Tα1-C14 (last 14 amino acids), retained this activity. Importantly, none of the analogues reduced penetration or altered overall sperm motility compared to the control group. This experiment showed that the key active site is mainly located in the last 14 amino acids, but that full efficacy depends on the retention of both the front and back of the molecule. Furthermore, Tα1-Gly-NH₂ performed as well as natural Tα1, making it a promising and potentially more stable candidate for the treatment of male infertility [25].

Lowers blood sugar levels and protects insulin-producing cells

Tα1 helps control high blood sugar levels and protects the pancreas from damage in experimental diabetes. Qiu and colleagues (2009) administered the diabetes-inducing drug streptozotocin (STZ) to C57BL/6 mice and then gave them Tα1 once daily for 35 days at a dose of 0.1 µg/kg or 1 µg/kg injected into the abdomen. Importantly, both doses significantly reduced blood sugar levels compared to untreated diabetic mice, although glucose levels did not completely return to normal. Interestingly, the higher dose doubled blood insulin levels (p < 0.001), showing improved β-cell function. In addition, histological examination of the pancreas showed less inflammation, less shrinkage of pancreatic islets and reduced loss of insulin-producing cells. Antioxidant protection was also improved: glutathione (GSH) levels increased approximately 1.92-fold (p < 0.01), malondialdehyde (MDA) levels fell to 81.9% diabetic levels (p < 0.05), and superoxide dismutase (SOD) and catalase activities increased. As a result, Tα1 helped to lower glucose levels, maintain insulin secretion, protect pancreatic cells and enhance antioxidant systems. These combined effects confirm its potential as a complementary therapy in diabetes through its anti-inflammatory and antioxidant effects [26].

Reduces intestinal toxicity resulting from cancer immunotherapy

Tα1 can protect the gut from harmful immune responses induced by checkpoint inhibitor therapy without impairing its anti-tumour effect. Renga and colleagues (2020) used a mouse model of colitis induced by CTLA-4 blockade. Importantly, Tα1 prevented severe intestinal inflammation type ' ' and tissue damage associated with this treatment, but still allowed the anticancer drug to act against tumours. Mechanistic studies showed that Tα1 activated the IDO1-dependent tolerogenic pathway to calm intestinal immunity, but did not increase IDO1 levels in tumours. In addition, it transformed the tumour microenvironment by altering T-cell entry, reversing the CD8⁺/Treg balance and altering dendritic cell signalling and maturation. As a result, gut effects were reduced and tumour-fighting immunity remained intact. These findings suggest that Tα1 may be a valuable adjuvant drug that enhances the safety of checkpoint inhibitors without blocking their therapeutic benefits [27].

Restores immune defences and enhances antifungal therapy

Tα1 can enhance the effects of antifungal drugs and rebuild the body's natural immune response to opioid-induced immunosuppression. Di Francesco and co-workers (1994) conducted studies on mice infected with 10⁶ Candida albicans, including some mice with morphine-induced immunosuppression. All animals received fluconazole (dose not stated in the summary) or Tα1 alone, or a combination of the two drugs. Importantly, the combination of Tα1 and fluconazole significantly prolonged survival and reduced fungal burden in the kidneys compared with either drug alone. Mechanistic studies showed that morphine impaired neutrophil killing capacity (PMN) and natural killer (NK) cell activity. Tα1 or fluconazole used alone helped to restore these immune functions, and the combination of the two substances improved them further, probably by modifying lymphokine signalling. Interestingly, fluconazole worked well in healthy mice, but lost most of its effect in morphine-deficient animals; the addition of Tα1 restored its antitumour effect. Taken together, these results suggest that Tα1 may synergise with antifungal drugs to combat systemic candidiasis by restoring innate immune responses in weakened hosts [28]. 

Dose of thymosin-α1 (Tα1)

Reported studies show that Tα1 is most commonly administered at a fixed dose of 1.6 mg subcutaneously (SC) per administration, usually twice a week. In some conditions, such as immune thrombocytopenia (ITP), it has been used three times a week, while short daily doses (usually 4-7 days) occur during intensive care or chemotherapy cycles. Importantly, one randomised controlled trial in severe acute pancreatitis (SAP) used a higher total daily dose of 3.2 mg administered subcutaneously twice daily for seven days. In addition, treatment regimens based on body size emerged in HIV supportive therapy, where weekly subcutaneous injections were increased from 400 to 1600 µg/m².  The duration of treatment varies widely, from 1-2 weeks for the treatment of acute or critical conditions to 8-12 weeks in pilot studies of reconstitution or immune depression, and schedules per cycle are common in combination with chemotherapy.

Disclaimer

This article has been written for educational purposes and is intended to raise awareness of the substance under discussion. It is important to note that the article is about the substance in general - it is not a description of a specific product (chemical reagent). We are not suggesting the use of chemical reagents on humans - this is prohibited by law, for a product to be used for treatment it must be registered as a medicine. The information contained in the text is based on available scientific research and is not intended as medical advice or to promote self-medication. The reader should consult with a qualified health professional for all health and treatment decisions.

References

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