RP1 Dominant p.Ser740* Pathogenic Variant in 20 Knowingly Unrelated Families Affected by Rod-Cone Dystrophy: Potential Founder Effect in Western Sicily.

Background and Objectives. Retinitis pigmentosa (RP) is the most common inherited rod-cone dystrophy (RCD), resulting in nyctalopia, progressive visual field, and visual acuity decay in the late stages. The autosomal dominant form (ADRP) accounts for about 20% of RPs. Among the over 30 genes found to date related to ADRP, RP1 pathogenic variants have been identified in 5-10% of cases. In a cohort of RCD patients from the Palermo province on the island of Sicily, we identified a prevalent nonsense variant in RP1, which was associated with ADRP. The objective of our study was to analyse the clinical and molecular data of this patient cohort and to evaluate the potential presence of a founder effect. Materials and Methods. From 2005 to January 2023, 84 probands originating from Western Sicily (Italy) with a diagnosis of RCD or RP and their relatives underwent deep phenotyping, which was performed in various Italian clinical institutions. Molecular characterisation of patients and familial segregation of pathogenic variants were carried out in different laboratories using Sanger and/or next-generation sequencing (NGS). Results. Among 84 probands with RCD/RP, we found 28 heterozygotes for the RP1 variant c.2219C>G, p.Ser740* ((NM_006269.2)*, which was therefore significantly prevalent in this patient cohort. After a careful interview process, we ascertained that some of these patients shared the same pedigree. Therefore, we were ultimately able to define 20 independent family groups with no traceable consanguinity. Lastly, analysis of clinical data showed, in our patients, that the p.Ser740* nonsense variant was often associated with a late-onset and relatively mild phenotype. Conclusions. The high prevalence of the p.Ser740* variant in ADRP patients from Western Sicily suggests the presence of a founder effect, which has useful implications for the molecular diagnosis of RCD in patients coming from this Italian region. This variant can be primarily searched for in RP-affected subjects displaying compatible modes of transmission and phenotypes, with an advantage in terms of the required costs and time for analysis. Moreover, given its high prevalence, the RP1 p.Ser740* variant could represent a potential candidate for the development of therapeutic strategies based on gene editing or translational read-through therapy for suppression of nonsense variants.

Development of a Thalassemia International Prognostic Scoring System (TIPSS).

A prognostic scoring system that can differentiate ß-thalassemia patients based on mortality risk is lacking. We analysed data from 3145 ß-thalassemia patients followed through a retrospective cohort design for the outcome of death. An a priori list of prognostic variables was collected. ß Coefficients from a multivariate cox regression model were used from a development dataset (n = 2516) to construct a formula for a Thalassemia International Prognostic Scoring System (TIPSS) which was subsequently applied to a validation dataset (n = 629). The median duration of observation was 10.0 years. The TIPSS score formula was constructed as exp (1.4 × heart disease + 0.9 × liver disease + 0.9 × diabetes + 0.9 × sepsis + 0.6 × alanine aminotransferase ≥42 IU/L + 0.6 × hemoglobin ≤9 g/dL + 0.4 × serum ferritin ≥1850 ng/mL). TIPSS score thresholds of greatest differentiation were assigned as <2.0 (low-risk), 2.0 to <5.0 (intermediate-risk), and ≥5.0 (high-risk). The TIPSS score was a good predictor for the outcome of death in the validation dataset (AUC: 0.722, 95%CI: 0.641-0.804) and survival was significantly different between patients in the three risk categories (P < 0.001). Compared to low-risk patients, the hazard ratio for death was 2.778 (95%CI: 1.335-5.780) in patients with intermediate-risk and 6.431 (95%CI: 3.151-13.128) in patients with high-risk. This study provides a novel tool to support mortality risk categorization for patients with ß-thalassemia that could help management and research decisions.

Primary HBB gene mutation severity and long-term outcomes in a global cohort of ß-thalassaemia.

In ß-thalassaemia, the severity of inherited ß-globin gene mutations determines the severity of the clinical phenotype at presentation and subsequent transfusion requirements. However, data on associated long-term outcomes remain limited. We analysed data from 2109 ß-thalassaemia patients with available genotypes in a global database. Genotype severity was grouped as ß0 /ß0 , ß0 /ß+ , ß+ /ß+ , ß0 /ß++ , ß+ /ß++ , and ß++ /ß++ . Patients were followed from birth until death or loss to follow-up. The median follow-up time was 34·1 years. Mortality and multiple morbidity outcomes were analyzed through five different stratification models of genotype severity groups. Interestingly, ß0 and ß+ mutations showed similar risk profiles. Upon adjustment for demographics and receipt of conventional therapy, patients with ß0 /ß0 , ß0 /ß+ , or ß+ /ß+ had a 2·104-increased risk of death [95% confidence interval (CI): 1·176-3·763, P = 0·011] and 2·956-increased odds of multiple morbidity (95% CI: 2·310-3·784, P < 0·001) compared to patients in lower genotype severity groups. Cumulative survival estimates by age 65 years were 36·8% for this subgroup compared with 90·2% for patients in lower genotype severity groups (P < 0·001). Our study identified mortality and morbidity risk estimates across various genotype severity groups in patients with ß-thalassaemia and suggests inclusion of both ß+ and ß0 mutations in strata of greatest severity.

A complication risk score to evaluate clinical severity of thalassaemia syndromes.

The thalassaemia syndromes (TS) show different phenotype severity. Developing a reliable, practical and global tool to determine disease severity and tailor treatment would be of great value. Overall, 7910 patients were analysed with the aim of constructing a complication risk score (CoRS) to evaluate the probability of developing one or more complications. Nine independent variables were included in the investigation as predictors. Logistic regression models were used for Group A [transfusion-dependent thalassaemia (TDT)], Group B [transfused non-TDT (NTDT)] and Group C (non-transfused NTDT). Statistically significant predictors included age (years), haemoglobin levels, hepatic transaminases [alanine aminotransferase (ALT) and aspartate aminotransferase] and left-ventricular ejection fraction (LVEF) for Group A; age (years), age at first chelation (months), ALT and LVEF for Group B; and age (years), mean serum ferritin (SF) levels and LVEF for Group C. The area under the receiver operating characteristic curve was 84·5%, 82·1% and 80·0% for Groups A, Group B and Group C respectively, suggesting the models had good discrimination. Finally, the CoRS for each group was categorised into four risk classes (low, intermediate, high, and very high) using the centiles of its distribution. In conclusion, we have developed a CoRS for TS that can assist physicians in prospectively tailoring patients' treatment.

Longitudinal changes in LIC and other parameters in patients receiving different chelation regimens: Data from LICNET.

OBJECTIVES: The liver remains the primary site of iron storage, with liver iron concentration (LIC) being a strong surrogate of total body iron. MRI-R2 can accurately measure LIC. The LICNET (Liver Iron Cutino Network) was established to diagnostics of liver iron overload by MRI-R2 subjects with hemochromatosis in hematological disorders. The aims of the study were to look at variation in LIC measurements during time across different chelation regimens. METHODS: This was a cross-sectional study of 130 patients attending 9 Italian centers participating in the LICNET. LIC comparisons over time (T0 and T1 ) were made using t test and/or Wilcoxon test. RESULTS: LIC significantly decreased from MRI1 to MRI2 although at high variance (median change -0.8 mg Fe/g dw, range: -29.0 to 33.0; P = .011) and 7.7% of patients shifted from LIC values of high risk (>15 mg Fe/g dw) to an intermediate-risk category (7-15 mg Fe/g dw). Median change in LIC and correlation with serum ferritin levels (SF), during different chelation regimens, is reported. CONCLUSIONS: These findings suggest as longitudinal variation in the LIC is possible, across all chelation regimens. It confirms as SF levels not always can be used for estimating changes in LIC.

Left Ventricular Diastolic Dysfunction in ß-Thalassemia Major with Heart Failure.

We studied the clinical, electrocardiographic, echocardiographic, Doppler and T2* cardiac magnetic resonance (CMR) data of all adult ß-thalassemia major (ß-TM) patients with heart failure (HF) consecutively observed at our referral center of the Sicilian region between 2008 and 2016. There were 16 patients enrolled in the study. Echocardiographic examination showed that only one patient had HF with systolic dysfunction of the left ventricle (HFrEF), whereas the others had HF with preserved systolic function of the left ventricle (HFpEF). Systolic dysfunction of the right ventricle (RV) was observed in 13 cases. Furthermore, 30.0% of the patients presented T2* CMR values consistent with intermediate risk of systolic dysfunction of the left ventricle (LV) due to iron overload, whereas 70.0% had normal values. Typical electrocardiographic abnormalities (wide T wave inversion and low voltages) were observed in 11 out of 16 patients. In conclusion, in the adult ß-TM patients with HF recently observed at our center, the predominant form was that with diastolic dysfunction of the LV, and with systolic dysfunction of the RV. Only 30.0% had low values of T2* CMR. Typical electrocardiographic abnormalities were found in 69.0%.

The era of comparable life expectancy between thalassaemia major and intermedia: Is it time to revisit the major-intermedia dichotomy?

In the last few decades, the life expectancy of regularly transfused ß-thalassaemia major (TM) patients has dramatically improved following the introduction of safe transfusion practices, iron chelation therapy, aggressive treatment of infections and improved management of cardiac complications. How such changes, especially those attributed to the introduction of iron chelation therapy, improved the survival of TM patients to approach those with ß-thalassaemia intermedia (TI) remains unknown. Three hundred and seventy-nine patients with TM (n = 284, dead 40) and TI (n = 95, dead 13) were followed retrospectively since birth until 30 June 2015 or death. Kaplan-Meir curves showed statistically significant differences in TM and TI survival (P < 0·0001) before the introduction of iron chelation in 1965, which were no longer apparent after that date (P = 0·086), reducing the Hazard Ratio of death in TM compared to TI from 6·8 [95% confidence interval (CI) 2·6-17·5] before 1965 to 2·8 (95% CI 0·8-9·2). These findings suggest that, in the era of iron chelation therapy and improved survival for TM, the major-intermedia dichotomy needs to be revisited alongside future directions in general management and prevention for both conditions.

Real-life experience with liver iron concentration R2 MRI measurement in patients with hemoglobinopathies: baseline data from LICNET.

BACKGROUND: Real-life data on the use of R2 MRI for the assessment of liver iron concentration (LIC) remain limited. METHODS: We conducted a cross-sectional analysis on 363 patients (mean age 35.6 yr, 44.1% men) with hemoglobinopathies (204 ß-thalassemia major [TM], 102 ß-thalassemia intermedia [TI], and 57 sickle cell disease [SCD]) that were evaluated with R2 MRI as part of LICNET, an MRI network of 13 Italian treatment centers. RESULTS: The mean LIC was 7.8 mg/g (median: 4.0), with high LIC (>7 mg/g) noted in both transfused (TM, TI 37%; SCD 38%) and non-transfused (TI 20%) patients. Ferritin levels correlated with LIC in both transfused (TM, TI, SCD) and non-transfused (TI) patients (P < 0.001), although lower values predicted high LIC in non-transfused patients (1900 vs. 650 ng/mL in TM vs. non-transfused TI). A correlation between LIC and ALT levels was only noted in HCV-negative patients (rs = 0.316, P < 0.001). The proportion of patients with high LIC was significantly different between iron chelators used (P = 0.023), with the lowest proportion in deferasirox (30%) and highest in deferiprone (53%)-treated patients. CONCLUSIONS: High LIC values persist in subgroups of patients with hemoglobinopathy, warranting closer monitoring and management optimization, even for non-transfused patients with relatively low ferritin levels.

Deferiprone versus deferoxamine in thalassemia intermedia: Results from a 5-year long-term Italian multicenter randomized clinical trial.

In patients with thalassemia intermedia (TI), such as beta-TI, alpha-thalassemia (mainly HbH disease and mild/moderate forms of HbE/beta-thalassemia), iron overload is an important challenge in terms of diagnosis, monitoring, and treatment. Moreover, to date, the only possible chelators available are deferoxamine, deferasirox, and deferiprone. Here, we report the first 5-year long-term randomized clinical trial comparing the effectiveness of deferiprone versus deferoxamine in patients with TI. Body iron burden, which was determined by measuring serum ferritin levels in the same patient over 5 years and analyzed according to the generalized linear mixed model (GLMM), showed a linear decrease over time in the mean serum ferritin levels in both treatment groups (P-value = 0.035). The overall period of observation was 235.2 person-years for the deferiprone patients compared with 214.3 person-years for the deferoxamine patients. The results of the log-rank test suggested that the deferiprone treatment did not affect survival compared with the deferoxamine treatment (P-value = 0.360). The major adverse events observed included gastrointestinal symptoms and joint pain or arthralgia. Neutropenia and agranulocytosis were also detected, suggesting needing of strict hematological control. In conclusion, long-term iron chelation therapy with deferiprone is associated with an efficacy and safety similar to that of deferoxamine, suggesting that this drug is an alternative option in cases in which deferoxamine and deferasirox are contraindicated.

Deferiprone versus deferoxamine in sickle cell disease: results from a 5-year long-term Italian multi-center randomized clinical trial.

Blood transfusion and iron chelation currently represent a supportive therapy to manage anemia, vasculopathy and vaso-occlusion crises in Sickle-Cell-Disease. Here we describe the first 5-year long-term randomized clinical trial comparing Deferiprone versus Deferoxamine in patients with Sickle-Cell-Disease. The results of this study show that Deferiprone has the same effectiveness as Deferoxamine in decreasing body iron burden, measured as repeated measurements of serum ferritin concentrations on the same patient over 5-years and analyzed according to the linear mixed-effects model (LMM) (p=0.822). Both chelators are able to decrease, significantly, serum ferritin concentrations, during 5-years, without any effect on safety (p=0.005). Moreover, although the basal serum ferritin levels were higher in transfused compared with non-transfused group (p=0.031), the changes over time in serum ferritin levels were not statistically significantly different between transfused and non-transfused cohort of patients (p=0.389). Kaplan-Meier curve, during 5-years of study, suggests that Deferiprone does not alter survival in comparison with Deferoxamine (p=0.38). In conclusion, long-term iron chelation therapy with Deferiprone was associated with efficacy and safety similar to that of Deferoxamine. Therefore, in patients with Sickle-Cell-Disease, Deferiprone may represent an effective long-term treatment option.

Serial echocardiographic left ventricular ejection fraction measurements: a tool for detecting thalassemia major patients at risk of cardiac death.

Cardiac damage remains a major cause of mortality among patients with thalassemia major. The detection of a lower cardiac magnetic resonance T2* (CMR-T2*) signal has been suggested as a powerful predictor of the subsequent development of heart failure. However, the lack of worldwide availability of CMR-T2* facilities prevents its widespread use for follow-up evaluations of cardiac function in thalassemia major patients, warranting the need to assess the utility of other possible procedures. In this setting, the determination of left ventricular ejection fraction (LVEF) offers an accurate and reproducible method for heart function evaluation. These findings suggest a reduction in LVEF≥7%, over time, determined by 2-D echocardiography, may be considered a strong predictive tool for the detection of thalassemia major patients with increased risk of cardiac death. The reduction of LVEF≥7% had higher (84.76%) predictive value. Finally, Kaplan-Meier survival curves of thalassemia major patients with LVEF≥7% showed a statistically significant decreased probability of survival for heart disease (p=0.0022). However, because of limitations related to the study design, such findings should be confirmed in a large long-term prospective clinical trial.

Long-term treatment with deferiprone enhances left ventricular ejection function when compared to deferoxamine in patients with thalassemia major.

Transfusion and iron chelation treatment have significantly reduced morbidity and improved survival of patients with thalassemia major. However, cardiac disease continues to be the most common cause of death. We report the left-ventricular ejection fraction, determined by echocardiography, in one hundred sixty-eight patients with thalassemia major followed for at least 5years who received continuous monotherapy with deferoxamine (N=108) or deferiprone (N=60). The statistical analysis, using the generalized estimating equations model, indicated that the group treated with deferiprone had a significantly better left-ventricular ejection fraction than did those treated with deferoxamine (coefficient 0.97; 95% CI 0.37; 1.6, p=0.002). The heart may be particularly sensitive to iron-induced mitochondrial damage because of the large number of mitochondria and its low level of antioxidants. Deferiprone, because of its lower molecular weight, might cross into heart mitochondria more efficiently, improving their activity and, thereby, myocardial cell function. Our findings indicate that the long-term administration of deferiprone significantly enhances left-ventricular function over time in comparison with deferoxamine treatment. However, because of limitations related to the design of this study, these findings should be confirmed in a prospective, randomized clinical trial.

Long-term use of deferiprone significantly enhances left-ventricular ejection function in thalassemia major patients.

A multicenter randomized open-label long-term sequential deferiprone­deferoxamine (DFP-DFO) versus DFP alone trial (sequential DFP-DFO) performed in patients with thalassemia major (TM) was retrospectively reanalyzed to assess the variation in the left ventricular ejection fraction (LVEF) [1].

Chelation treatment in sickle-cell-anaemia: much ado about nothing?

Blood transfusions may prevent and treat serious complications related to sickle-cell disease (SCD) when performed according to specific guidelines. However, blood transfusion requirements in SCD inevitably lead to increased body iron burden. An adequate chelation treatment may prevent complications and reduce morbidity and mortality. This review evaluates the effectiveness, safety and costs of chelation treatment. The included trials were examined according to the recommendations of the American College of Cardiology (ACC) and the American Heart Association (AHA). Overall, 14 trials and a total of 502 patients with SCD were included in this review. Deferoxamine alone (s.c. or i.v.), deferiprone alone or versus deferoxamine, deferasirox versus deferoxamine and combined treatment with deferoxamine plus deferiprone were included and evaluated in the analysis. Only two randomized clinical trials have been reported. The results of this analysis suggest that use of chelation treatment in SCD to date has been based on little efficacy and safety evidence, although it is widely recommended and practised. The cost/benefit ratio has not been fully explored. Further research with larger randomized clinical trials needs to be performed.

Iron chelation therapy in thalassemia major: a systematic review with meta-analyses of 1520 patients included on randomized clinical trials.

The effectiveness of deferoxamine (DFO), deferiprone (DFP), or deferasirox (DFX) in thalassemia major was assessed. Outcomes were reported as means±SD, mean differences with 95% CI, or standardized mean differences. Statistical heterogeneity was tested using χ2 (Q) and I2. Sources of bias and Grading of Recommendations Assessment, Development and Evaluation system (GRADE) were considered. Overall, 1520 patients were included. Only 7.4% of trials were free of bias. Overall measurements suggest low trial quality (GRADE). The meta-analysis suggests lower final liver iron concentrations during associated versus monotherapy treatment (p<0.0001), increases in serum ferritin levels during DFX 5, 10, and 20 mg/kg versus DFO-treated groups (p<0.00001, p<0.00001, and p=0.002, respectively), but no statistically significant difference during DFX 30 mg/kg versus DFO (p=0.70), no statistically significant variations in heart T2* signal during associated or sequential versus mono-therapy treatment (p=0.46 and p=0.14, respectively), increases in urinary iron excretion during associated or sequential versus monotherapy treatment (p=0.008 and p=0.02, respectively), and improved ejection fraction during associated or sequential versus monotherapy treatment (p=0.01 and p<0.00001, respectively). These findings do not support any specific chelation treatment. The literature shows risks of bias, and additional larger and longer trials are needed.

Sequential alternating deferiprone and deferoxamine treatment compared to deferiprone monotherapy: main findings and clinical follow-up of a large multicenter randomized clinical trial in -thalassemia major patients.

In ß-thalassemia major (ß-TM) patients, iron chelation therapy is mandatory to reduce iron overload secondary to transfusions. Recommended first line treatment is deferoxamine (DFO) from the age of 2 and second line treatment after the age of 6 is deferiprone (L1). A multicenter randomized open-label trial was designed to assess the effectiveness of long-term alternating sequential L1-DFO vs. L1 alone iron chelation therapy in ß-TM patients. Deferiprone 75 mg/kg 4 days/week and DFO 50 mg/kg/day for 3 days/week was compared with L1 alone 75 mg/kg 7 days/week during a 5-year follow-up. A total of 213 thalassemia patients were randomized and underwent intention-to-treat analysis. Statistically, a decrease of serum ferritin level was significantly higher in alternating sequential L1-DFO patients compared with L1 alone patients (p = 0.005). Kaplan-Meier survival analysis for the two chelation treatments did not show statistically significant differences (log-rank test, p = 0.3145). Adverse events and costs were comparable between the groups. Alternating sequential L1-DFO treatment decreased serum ferritin concentration during a 5-year treatment by comparison to L1 alone, without significant differences of survival, adverse events or costs. These findings were confirmed in a further 21-month follow-up. These data suggest that alternating sequential L1-DFO treatment may be useful for some ß-TM patients who may not be able to receive other forms of chelation treatment.