A child with severe iron-deficiency anemia and a complex TMPRSS6 genotype

Sucrosomial® Iron: An Updated Review of Its Clinical Efficacy for the Treatment of Iron Deficiency

Iron deficiency (ID) and iron deficiency anemia (IDA) are highly prevalent worldwide. Oral iron salts, especially ferrous sulfate, are commonly used for the treatment of iron deficiency (ID). However, its use is associated with gastrointestinal side effects, thus compromising treatment compliance. Intravenous iron administration is a more costly and logistically complex alternative and is not risk-free, as infusion and hypersensitivity reactions may occur. Sucrosomial^® iron is an oral formulation consisting of ferric pyrophosphate conveyed by a phospholipid and sucrester matrix (sucrosome^®). Intestinal Sucrosomial^® iron absorption is mediated by enterocytes and M cells, through the paracellular and transcellular routes, and occurs mostly as intact particles. These pharmacokinetic properties of Sucrosomial^® iron result in higher iron intestinal absorption and excellent gastrointestinal tolerance compared to oral iron salts. The evidence derived from clinical studies supports the use of Sucrosomial^® iron as a valid first option for the treatment of ID and IDA, especially for subjects who are intolerant or refractory to conventional iron salts. Newer evidence also demonstrates the effectiveness of Sucrosomial^® iron, with a lower cost and fewer side effects, in certain conditions usually treated with IV iron in current clinical practice.

Response to Prolonged Duration of Therapeutic Dose Oral Iron Therapy in a Girl With Novel TMPRSS6 Gene Variants: A Case Report and Review Literature

Iron-refractory iron deficiency anemia (IRIDA) is an autosomal recessive disorder caused by mutations in the TMPRSS6 gene, which impair iron homeostasis. We reported a 4-year-old girl who presented with a 1-year history of iron deficiency anemia. Her hemoglobin level increased from 6.5 g/dL to 12.6 g/dL with a prolonged duration of therapeutic dose oral iron therapy (5 mg/kg/d), and the level remained quite stable during the therapy. Genetic analysis of the TMPRSS6 gene revealed compound heterozygotes of 2 novel pathogenic variants: c.811C> T (NM_153609.3) in exon 7 (NP_705837: p.R271Ter) and c.1254C> G in exon 11 (p.Y418Ter). The results highlight the significance of genetic investigation and long-term iron therapy in iron-refractory iron deficiency anemia patients.

IRIDA Phenotype in TMPRSS6 Monoallelic-Affected Patients: Toward a Better Understanding of the Pathophysiology

Iron-refractory iron deficiency anemia (IRIDA) is an autosomal recessive inherited form of iron deficiency anemia characterized by discrepantly high hepcidin levels relative to body iron status. However, patients with monoallelic exonic TMPRSS6 variants have also been reported to express the IRIDA phenotype. The pathogenesis of an IRIDA phenotype in these patients is unknown and causes diagnostic uncertainty. Therefore, we retrospectively summarized the data of 16 patients (4 men, 12 women) who expressed the IRIDA phenotype in the presence of only a monoallelic TMPRSS6 variant. Eight unaffected relatives with identical exonic TMPRSS6 variants were used as controls. Haplotype analysis was performed to assess the (intra)genetic differences between patients and relatives. The expression and severity of the IRIDA phenotype were highly variable. Compared with their relatives, patients showed lower Hb, MCV, and TSAT/hepcidin ratios and inherited a different wild-type allele. We conclude that IRIDA in monoallelic TMPRSS6-affected patients is a phenotypically and genotypically heterogeneous disease that is more common in female patients. We hypothesize that allelic imbalance, polygenetic inheritance, or modulating environmental factors and their complex interplay are possible causes. This explorative study is the first step toward improved insights into the pathophysiology and improved diagnostic accuracy for patients presenting with IRIDA and a monoallelic exonic TMPRSS6 variant.

Randomized trial of sucrosomial iron supplementation in patients with chemotherapy-related anemia treated with ESA

BACKGROUND

Iron supplementation improves the erythropoiesis-stimulating agents' (ESAs) response in chemotherapy-related anemia. The primary aim of our study is to assess the efficacy of sucrosomial iron, a new oral iron formulation, in cancer patients with chemotherapy-induced anemia treated with ESAs. The secondary objectives included the efficacy into two subgroups of patients (iron replete and functional iron deficiency) between the two study arms, safety and the effect on transfusion need.

METHODS

In this randomized, multicentre, open-label, phase III clinical trial, 60 cancer patients were enrolled. Each patient was randomly assigned (1:1) to receive 12 weeks of oral sucrosomial iron at the dose of 30 mg daily in combination with ESAs or no supplementation to ESA treatment. The endpoint considered for efficacy was the proportion of patients achieving complete hematological response at 12 weeks (increase in Hb > 2 g/dL from baseline, without RBC transfusions in the previous 28 days or achieving Hb ≥ 12 g/dL).

RESULTS

There was a statistically significant association between oral sucrosomial iron supplementation in combination with ESAs and the achievement of a complete hematological response. This response was achieved within 12 weeks by 31% of patients in the control group and by 52% of patients supplemented with oral sucrosomial iron. A trend of greater response in sucrosomial iron arm was found in both subgroups. No difference was observed about safety and transfusion need.

CONCLUSIONS

Sucrosomial iron is well tolerated and its combination with ESAs improves the hematological response in cancer patients with chemotherapy-related anemia.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

This study has been reviewed by the Institutional Ethics Committee of the IRCCS Policlinico San Matteo Foundation, Pavia, Italy (28/04/2015; prot. N. 20,150,002,059), and by the Institutional Ethics Committee of the other Italian oncological centers involved in this study.

Iron distribution in different tissues of homozygous Mask (msk/msk) mice and the effects of oral iron treatments

Iron-refractory iron deficiency anemia (IRIDA) is an autosomal recessive disorder caused by genetic mutations on TMPRSS6 gene which encodes Matriptase2 (MT2). An altered MT2 cannot appropriately suppress hepatic BMP6/SMAD signaling in case of low iron, hence hepcidin excess blocks dietary iron absorption, leading to a form of anemia resistant to oral iron supplementation. In this study, using the IRIDA mouse model Mask, we characterized homozygous (msk/msk) compared to asymptomatic heterozygous (msk/wt) mice, assessing the major parameters of iron status in different organs, at different ages in both sexes. The effect of carbonyl iron diet was analyzed as control iron supplementation being used for many studies in mice. It resulted effective in both anemic control and msk/msk mice, as expected, even if there is no information about its mechanism of absorption. Then, we mainly compared two forms of oral iron supplement, largely used for humans: ferrous sulfate and Sucrosomial iron. In anemic control mice, the two oral formulations corrected hemoglobin levels from 11.40 ± 0.60 to 15.38 ± 1.71 g/dl in 2-4 weeks. Interestingly, in msk/msk mice, ferrous sulfate did not increase hemoglobin likely due to ferroportin/hepcidin-dependent absorption, whereas Sucrosomial iron increased it from 11.50 ± 0.60 to 13.53 ± 0.64 g/dl mainly in the first week followed by a minor increase at 4 weeks with a stable level of 13.30 ± 0.80 g/dl, probably because of alternative absorption. Thus, Sucrosomial iron, already used in other conditions of iron deficiency, may represent a promising option for oral iron supplementation in IRIDA patients.

Personalized Nutrition for Management of Micronutrient Deficiency-Literature Review in Non-bariatric Populations and Possible Utility in Bariatric Cohort

Background

Bariatric surgery can effectively treat morbid obesity; however, micronutrient deficiencies are common despite recommendations for high-dose supplements. Genetic predisposition to deficiencies underscores necessary identification of high-risk candidates. Personalized nutrition (PN) can be a tool to manage these deficiencies.

Methods

Medline, PubMed, and Google Scholar were searched. Articles involving genetic testing, micronutrient metabolism, and bariatric surgery were included.

Results

Studies show associations between genetic variants and micronutrient metabolism. Research demonstrates genetic testing to be a predictor for outcomes among obesity and bariatric surgery populations. There is limited research in bariatric surgery and micronutrient genetic variants.

Conclusion

Genotype-based PN is becoming feasible to provide an effective treatment of micronutrient deficiencies associated with bariatric surgery. The role of genomic technology in micronutrient recommendations needs further investigation.

Two Novel TMPRSS6 Variants in a Compound Heterozygous Child With Iron Refractory Iron Deficiency Anemia

We describe a Caucasian family with asymptomatic, nonconsanguineous parents, and a daughter with unexplained microcytic anemia diagnosed on routine hemoglobin screening at her 12-month well child check. After failed response to oral and parental iron supplementation, iron refractory iron deficiency anemia was suspected. The family underwent genetic testing and the proband was found to be a compound heterozygote for 2 previously unreported TMPRSS6 variants.

Natural selection on TMPRSS6 associated with the blunted erythropoiesis and improved blood viscosity in Tibetan pigs

Tibetan pigs, indigenous to Tibetan plateau, are well adapted to hypoxia. So far, there have been not any definitively described genes and functional sites responsible for hypoxia adaptation for the Tibetan pig. The whole genome-wide association studies in human suggested that genetic variations in TMPRSS6 was associated with hemoglobin concentration (HGB) and red cell counts (RBC). Here we conducted resequencing of the nearly entire genomic region (40.1 kb) of the candidate gene TMPRSS6 in 40 domestic pigs and 40 wild boars along continuous altitudes and identified 708 SNPs, in addition to an indel (CGTG/----) in the intron 10. We conduct the CGTG indel in 838 domestic pigs, both the CGTG deletion frequency and the pairwise r² linkage disequilibrium showed an increase with elevated altitudes, suggesting that TMPRSS6 has been under Darwinian positive selection. As the conserved core sequence of hypoxia-response elements (HREs), the deletion of CGTG in Tibetan pigs decreased the expression levels of TMPRSS6 mRNA and protein in the liver revealed by real-time quantitative PCR and western blot, respectively. We compared domestic pigs and Tibetan pigs living continuous altitudes, found that the blood-related traits with the increase of altitude, however, the HGB did not increase with the elevation in Tibetan pigs. Genotype association analysis results dissected a genetic effect on reducing HGB by 13.25 g/L in Gongbo'gyamda Tibetan pigs, decreasing mean corpuscular volume (MCV) by 4.79 fl in Diqing Tibetan pigs. In conclusion, the CGTG deletion of TMPRSS6 resulted in lower HGB and smaller MCV, which could reflect a blunting erythropoiesis and improving blood viscosity as well as erythrocyte deformability. It remains to be determined whether a blunting of erythropoiesis for TMPRSS6 or others genetic effects are the physiological adaptations among Tibetan pigs.

Sucrosomial® Iron: A New Generation Iron for Improving Oral Supplementation

Iron deficiency (ID) is usually treated with oral iron salts, but up to 50% of patients complain of gastrointestinal side effects, leading to reduced treatment compliance. Intravenous (IV) iron formulations are increasingly safer, but there is still a risk of infusion and hypersensitivity reactions and the need for a venous access and infusion monitoring. Sucrosomial® iron (SI) is an innovative oral iron formulation in which ferric pyrophosphate is protected by a phospholipid bilayer plus a sucrester matrix (sucrosome), which is absorbed through para-cellular and trans-cellular routes (M cells). This confers SI unique structural, physicochemical and pharmacokinetic characteristics, together with high iron bioavailability and excellent gastrointestinal tolerance. The analysis of available evidence supports oral SI iron as a valid option for ID treatment, which is more efficacious and better tolerated than oral iron salts. SI has also demonstrated similar effectiveness, with lower risks, in patients usually receiving IV iron (e.g., chronic kidney disease, cancer, bariatric surgery). Thus, oral SI emerges as a most valuable first option for treating ID, even more for subjects with intolerance to or inefficacy of iron salts. Moreover, SI should be also considered as an alternative to IV iron for initial and/or maintenance treatment in different patient populations.

Sucrosomial® Iron Supplementation in Mice: Effects on Blood Parameters, Hepcidin, and Inflammation

Sucrosomial^® Iron is a recently developed formulation to treat iron deficiency based on ferric pyrophosphate covered by a matrix of phospholipids plus sucrose esters of fatty acids. Previous data indicated that Sucrosomial^® Iron is efficiently absorbed by iron-deficient subjects, even at low dosage, and without side effects. Its structural properties may suggest that it is absorbed by an intestinal pathway which is different to the one used by ionic iron. Although, studies in vitro showed that Sucrosomial^® Iron is readily absorbed, no animal models have been established to study this important aspect. To this aim, we induced iron deficient anemia in mice by feeding them with a low-iron diet, and then we treated them with either Sucrosomial^® Iron or sulfate iron by gavage for up to two weeks. Both iron formulations corrected anemia and restored iron stores in a two-week period, but with different kinetics. Ferrous Sulfate was more efficient during the first week and Sucrosomial^® Iron in the second week. Of note, when given at the same concentrations, Ferrous Sulfate induced the expression of hepcidin and four different inflammatory markers (Socs3, Saa1, IL6 and CRP), while Sucrosomial^® Iron did not. We conclude that anemic mice are interesting models to study the absorption of oral iron, and that Sucrosomial^® Iron is to be preferred over Ferrous Sulfate because of similar absorption but without inducing an inflammatory response.

Sucrosomial Iron Supplementation in Anemic Patients with Celiac Disease Not Tolerating Oral Ferrous Sulfate: A Prospective Study

Patients with celiac disease (CD) frequently suffer from iron deficiency anemia (IDA) and may benefit from iron supplementation. However, intolerance to iron sulfate and duodenal atrophy could reduce the efficacy of this supplementation. This study evaluated the efficacy of a new sucrosomial iron formulation in patients with CD. Consecutive patients with CD and IDA were divided into two groups: patients with a known intolerance to iron sulfate were treated with sucrosomial iron (30 mg of iron/day), while those receiving iron supplementation for the first time were assigned to iron sulfate (105 mg of iron/day). Forty-three patients were enrolled (38 females, mean age 49 ± 9 years). After a follow-up of 90 days both groups showed an increase in Hb levels compared to baseline (+10.1% and +16.2% for sucrosomial and sulfate groups, respectively), and a significant improvement in all iron parameters, with no statistical difference between the two groups. Patients treated with sucrosomial iron reported a lower severity of abdominal symptoms, such as abdominal and epigastric pain, abdominal bloating, and constipation, and a higher increase in general well-being (+33% vs. +21%) compared to the iron sulfate group. Sucrosomial iron can be effective in providing iron supplementation in difficult-to-treat populations, such as patients with CD, IDA, and known intolerance to iron sulfate.

Position paper on management of iron deficiency in adult cancer patients

INTRODUCTION

Disorders of iron metabolism are commonly seen in onco-hematological clinical practice. Iron-deficiency anemia and cancer-associated anemia are usually treated with supportive therapies. Optimal management of these conditions are discussed in this perspective paper. Areas covered: A position paper discussing a number of hot topics on anemia in cancer patients is presented. The main areas covered by experts in the field are: definitions, prevalence and consequences of anemia and iron deficiency, incidence of anemia resulting from targeted therapies, importance of anemia diagnosis and monitoring, evaluation of iron status before and during treatment, role of transfusions and erythropoiesis-stimulating agents, management of iron deficiency with or without anemia, parenteral iron supplementation, role of new oral iron formulations, safety and cost issues regarding different iron compounds and administration routes. Expert commentary: Despite the availability of newer therapeutic options for its management, anemia still represents a major complication of treatment in cancer patients (surgery, chemotherapy, radiotherapy, targeted therapies), aggravating physical impairment, and negatively affecting general outcome. The view expressed by the panelists, attendees of the 4th Mediterranean Course on Iron Anemia, summarizes what they consider optimal clinical practice for screening, diagnosis, treatment and monitoring of iron deficiency and anemia in cancer patients.