Efficacy and safety of deferasirox estimated by serum ferritin and labile plasma iron levels in patients with aplastic anemia, myelodysplastic syndrome, or acute myeloid leukemia with transfusional iron overload

Dose of deferasirox correlates with its effects, which differ between low-risk myelodysplastic syndrome and aplastic anaemia

WHAT IS KNOWN AND OBJECTIVE

Patients with low-risk myelodysplastic syndrome (MDS) and aplastic anaemia (AA) often need transfusions, which may accelerate iron overload. The aim of this study was to evaluate the efficacy, safety and dose-effect relationships of deferasirox (DFX) in patients with low-risk MDS and AA who were refractory to regular treatment in a real-world setting.

METHODS

Patient data were recorded, and dose-effect relationships of DFX were calculated after the first 6 months. Total annual exposure to DFX was calculated after 12 months and expressed as the accumulated exposure time at a dosage of 20 mg/kg/day.

RESULTS AND DISCUSSION

Sixty-one patients with low-risk MDS and 51 with AA were enrolled. The minimum dosage of DFX needed for a significant serum ferritin (SF) decrease was 20 mg/kg/day at 6 months, and the minimum accumulation of DFX had to reach 9 months at 20 mg/kg/day by 12 months for patients with low-risk MDS. For patients with AA, the minimum dosage was 10 mg/kg/day at 6 months, and the minimum accumulation had to reach 3 months at 20 mg/kg/day by 12 months. With the same exposure, significant improvements in haematological parameters were also observed in AA. Lower liver enzymes compared with baseline were observed. Gastrointestinal disorders and elevated serum creatinine were the most common side effects. Higher exposure to DFX correlated with longer overall survival (OS).

WHAT IS NEW AND CONCLUSION

A significant decrease in SF and an improvement in haematologic parameters, organ function and even OS can be achieved if the accumulated DFX dose reaches a certain level. Patients with low-risk MDS need a higher dose than those with AA.

Impact of iron overload by transfusion on survival and leukemia transformation of myelodysplastic syndromes in a single center of China

INTRODUCTION

Myelodysplastic syndromes (MDS) are a heterogeneous group of diseases which are prone to progress into acute myeloid leukemia (AML). Iron overload (IOL) caused by transfusion occurred in most MDS patients. But how IOL influences MDS progression has not been clarified yet.

METHODS

Herein, we collected clinical data from 143 MDS patients to investigate the impacts of IOL on patients survival and AML transformation.

RESULTS

We found that median survival time, 3-year survival rate, leukemia-free survival (LFS) time were significantly shorter in patients with IOL than those with non-iron overload (NIOL) (P = 0.040; P = 0.044; P = 0.037). Besides, IOL was more likely to be found in higher-risk subgroups (assessed by IPSS and WPSS) of MDS patients which also promoted 2-year AML transformation. Furthermore, the serum ferritin (SF) was significantly correlated with the overall survival (OS) of MDS patients (r = -0.311, P < 0.05). The concentrations of both intracellular iron and reactive oxygen species (ROS) in CD34⁺ cells of bone marrow were higher in the IOL group than the NIOL group, respectively (P = 0.0426; P = 0.0185). Moreover, ROS level was closely correlated with the percentage of bone marrow blasts (r = 0.7200, P = 0.0370). Collectively, IOL threatened the survival of MDS patients and promoted AML transformation.

CONCLUSION

Elevated intracellular iron and ROS in CD34⁺ cells of bone marrow could accelerate the abnormal proliferation of blasts.

Safety and efficacy of deferasirox in patients with transfusion-dependent thalassemia: A 4-year single-center experience

This study was organized to determine the efficacy and safety of deferasirox (DFX) in reducing the SF of patients with transfusion-dependent thalassemia (TDT). This is a retrospective, descriptive study of 101 transfusion- dependent patients with thalassemia major who were followed for 48 months. Twenty-nine patients who used an alternative chelator either alone or combined, who were not compliant to the treatment, changed the drug due to adverse reactions, and had multiple transfusions and did not complete 4 years of DFX use were excluded. A total 72 out of 101 patients completed the study. SF decreases were noted for the 6-12 and >18-year age groups, from a median of 1532 ng/mL to 1190 ng/mL, and from 1386 ng/mL to 1165 ng/mL, respectively (p > 0.05). The proportion of patients with SF concentrations >2000 ng/mL is decreased (29% at baseline decreased to 15% at the end of the study) during the 48 months. The median SF of those who used <30 mg/kg/day (n = 38) increased from 767 ng/mL to 1006 ng/mL, whereas the >30 mg/kg/day (n = 34) group's SF concentrations decreased from a median of 1575 ng/mL to 1209 ng/mL (p = 0.029). The decrease of median SF values for Syrian patients was statistically significant (p = 0.043). Most common adverse events were gastric irritation symptoms (19.4%). The total DFX discontinuation ratio was calculated as 9.7%. Although dosages between 25-30 mg/kg/day are adequate to stabilize SF concentrations higher dosages are needed to achieve a statistically significant decrease.

Iron overload adversely effects bone marrow haematogenesis via SIRT-SOD2-mROS in a process ameliorated by curcumin

BACKGROUND

Iron overload, which is common in patients with haematological disorders, is known to have a suppressive effect on haematogenesis. However, the mechanism for this effect is still unclear. The antioxidant curcumin has been reported to protect against iron overload-induced bone marrow damage through an as-yet-unknown mechanism.

METHODS

We established iron overload cell and mouse models. Mitochondrial reactive oxygen species (mROS) levels, autophagy levels and the SIRT3/SOD2 pathway were examined in the models and in the bone marrow of patients with iron overload.

RESULTS

Iron overload was shown to depress haematogenesis and induce mitochondrion-derived superoxide anion-dependent autophagic cell death. Iron loading decreased SIRT3 protein expression, promoted an increase in SOD2, and led to the elevation of mROS. Overexpression of SIRT3 reversed these effects. Curcumin treatment ameliorated peripheral blood cells generation, enhanced SIRT3 activity, decreased SOD2 acetylation, inhibited mROS production, and suppressed iron loading-induced autophagy.

CONCLUSIONS

Our results suggest that curcumin exerts a protective effect on bone marrow by reducing mROS-stimulated autophagic cell death in a manner dependent on the SIRT3/SOD2 pathway.

The Effects of Dandelion Polysaccharides on Iron Metabolism by Regulating Hepcidin via JAK/STAT Signaling Pathway

Recent studies have claimed that iron overload was correlated with the risk of hepatocellular carcinoma (HCC), and our previous studies have also demonstrated that dandelion polysaccharide (DP) suppressed HCC cell line proliferation via causing cell cycle arrest and inhibiting the PI3K/AKT/mTOR pathway, but the effect of DP on metabolism is still not very clear. Here, we aim to clarify the effects of DP on iron metabolism and the underlying mechanism. In this study, we found that DP could reduce iron burden in hepatoma cells and grafted tumors. Hepcidin is a central regulator in iron metabolism. We confirmed that the expression of hepcidin in HCC tumor tissues was significantly higher than that in the adjacent nontumor tissues. The expression of hepcidin was downregulated in the liver of mouse model treatment with DP, as well as in hepatoma cells. Moreover, RNA sequencing and western blot data revealed that DP inhibited the IL-6-activated JAK-STAT signaling pathway. In summary, our results revealed that DP might be a new potential drug candidate for the regulation of iron burden and the treatment of HCC.

Role of redox iron towards an increase in mortality among patients: a systemic review and meta-analysis

An increase in biochemical concentrations of non-transferrin bound iron (NTBI) within the patients with an increase in serum iron concentration was evaluated with the following objectives: (a) Iron overloading diseases/conditions with free radicle form of ‘iron containing’ reactive oxygen species (ROS) and its imbalance mediated mortality, and (b) Intervention with iron containing drugs in context to increased redox iron concentration and treatment induced mortality. Literature search was done within Pubmed and cochrane review articles. The Redox iron levels are increased during dys-erythropoiesis and among transfusion recipient population and are responsive to iron-chelation therapy. Near expiry ‘stored blood units’ show a significant rise in the ROS level. Iron mediated ROS damage may be estimated by the serum antioxidant level, and show reduction in toxicity with high antioxidant, low pro-oxidant levels. Iron drug therapy causes a significant increase in NTBI and labile iron levels. Hospitalized patients on iron therapy however show a lower mortality rate. Serum ferritin is a mortality indicator among the high-dose iron therapy and transfusion dependent population. The cumulative difference of pre-chelation to post chelation ROS iron level was 0.97 (0.62; 1.32; N=261) among the transfusion dependent subjects and 2.89 (1.81–3.98; N=130) in the post iron therapy ‘iron ROS’ group. In conclusion, iron mediated mortality may not be mediated by redox iron among multi-transfused and iron overloaded patients.

Deferasirox in the treatment of iron overload during myeloproliferative neoplasms in fibrotic phase: does ferritin decrement matter?

Few data are available on the treatment with DFX in patients with transfusion dependent Ph- Myeloproliferative Neoplasms in fibrotic phase. Here we report 48MPNpatients and iron overload treated with DFX. Starting DFX dose was 20 mg/Kg in 23 patients, 15 mg/Kg in 20 patientsand 10 mg/Kg in 5 patients. After a median treatment of 27.6 months, 5 patients achieved ferritin<500 ng/ml, 11 < 1000 ng/ml and 3 a reduction >50% of basal ferritin with a global response rate of 41%. As to hematological improvement, 9/47 patients (19.1%) showed a persistent rise of Hb>1.5 g/dl, with disappearance of transfusion requirement in 6 cases. The median OS from DFX initiation in patients with chelation response was 61.0 months compared to 15.8 months in patients without chelation efficacy. Treatment with DFX is feasible and effective in MPN with iron overload and a hematological improvement can occur in a sizeable rate of patients.

Comparison of the effects of deferasirox, deferoxamine, and combination of deferasirox and deferoxamine on an aplastic anemia mouse model complicated with iron overload

Background and aim

Iron overload is commonly observed during the course of aplastic anemia (AA), which is believed to aggravate hematopoiesis, cause multiple organ dysfunction, lead to disease progression, and impair quality of life. Deferasirox (DFX) and deferoxamine (DFO) are among the most common iron chelation agents available in the clinical setting. The aim of this study was to investigate if the combination therapy with DFX and DFO is superior in hematopoietic recovery and iron chelation.

Methods

Briefly, we developed a composite mouse model with AA and iron overload that was consequently treated with DFX, DFO, or with a combination of both agents. The changes in peripheral hemogram, marrow apoptosis, and its related protein expressions were compared during the process of iron chelation, while the iron depositions in liver and bone marrow and its regulator were also detected.

Results

The obtained results showed that compared to DFX, DFO has a better effect in protecting the bone marrow from apoptosis-induced failure. The combination of DFO and DFX accelerated the chelation of iron, while their efficiency on further hemogram improvement appeared limited.

Conclusion

To sum up, our data suggest that single treatment with DFO may be a better choice for improving the hematopoiesis during the gradual chelation treatment irrespective of the convenience of oral DFX, while the combination treatment should be considered for urgent reduction of the iron burden.

Updated recommendations on the management of gastrointestinal disturbances during iron chelation therapy with Deferasirox in transfusion dependent patients with myelodysplastic syndrome - Emphasis on optimized dosing schedules and new formulations

Myelodysplastic syndromes (MDS) are oligoclonal hematopoietic disorders characterized by peripheral cytopenias with anemias being the most prevalent feature. The majority of patients will depend on regular transfusions of packed red blood cells (PRBC) during the course of the disease. Particularly patients with MDS and low risk for transformation into acute myeloid leukemia and low risk of early death will receive PRBC transfusions on a regular basis, which puts them at high risk for transfusional iron overload. Transfusion dependence has been associated with negative impact on organ function and reduced life expectancy. Recently, several retrospective but also some prospective studies have indicated, that transfusion dependent patients with MDS might benefit from consequent iron chelation with regard to morbidity and mortality. However, low treatment adherence due to adverse events mainly gastrointestinal in nature is an important obstacle in achieving sufficient iron chelation in MDS patients. Here, we will summarize and discuss the existing data on Deferasirox in low risk MDS published so far and provide recommendations for optimal management of gastrointestinal adverse events during iron chelation aiming at improving treatment compliance and, hence, sufficiently removing excess iron from the patients.