This study aims to assess the comparative effects of intravenous and liposomal oral iron on hemoglobin levels in non-dialysis CKD patients. Additionally, it seeks to evaluate the rate of hemoglobin correction, iron reserve status during treatment, and therapeutic tolerance to these interventions.

The last two and a half decades have seen erythropoiesis-stimulating agents (ESAs) and iron therapy at the forefront of managing anemia in chronic kidney disease (CKD) patients. While ESAs have demonstrated significant efficacy in alleviating anemia in this context, recent large-scale randomized controlled trials in both non-dialysis and dialysis CKD patients have shed light on their limitations. Attempts to normalize hemoglobin (Hb) levels with ESAs have shown no significant cardiovascular benefits but have been associated with increased risks of adverse events such as stroke and venous thromboembolism.

Consequently, there has been a reduction in ESA prescription and an increase in blood transfusions, coupled with a notable rise in the use of iron therapy due to its role in addressing hypo responsiveness to ESAs.

Anemia stands as a common complication in CKD, significantly impacting cardiovascular health and quality of life. While renal erythropoietin production deficit remains a primary cause, iron deficiency plays a pivotal role in CKD-related anemia genesis. Iron deficiency, whether absolute or functional, alongside an inflammatory block, often seen in CKD patients, accounts for the main reasons behind hypo responsiveness to erythropoiesis-stimulating agents.

The recent shift in focus from ESA-centered treatment to iron therapy has prompted debates regarding the ideal route of iron administration, particularly in non-dialysis CKD patients. Despite the benefits of oral iron-cost-effectiveness and ease of administration-its usage remains limited due to poor gastrointestinal absorption and high adverse event rates. Conversely, concerns about IV iron revolve around potential kidney damage, infections, atherosclerosis promotion, and other adverse reactions.

Given these considerations, our study aims to compare the efficacy of oral liposomal iron against IV iron in treating anemia in non-dialysis CKD patients in terms of :

1. Martial status under treatment.
2. Hemoglobin level and its correction speed.
3. Therapeutic tolerance.

Inclusion Criteria:

• Inclusion criteria for the study are age >18 years, eGFR ≤60 mL/min/1.73 m2 (Modification of Diet in Renal Disease equation: MDRD), Hb levels ≤12 g/dL, ferritin levels ≤100 ng/mL, transferrin saturation (TSAT) ≤25%, parathormone (PTH) serum levels between 30 and 300 pg/mL.

Exclusion Criteria:

• Exclusion criteria included presence of an inflammatory or infectious disease with a C-reactive protein (CRP) levels ≥6 mg/L at the beginning of the study ,surgical interventions in the last 3 months, hematological disorders including bleeding or blood transfusions in the last 6 months, malignancies, ongoing treatment with immunosuppressive drugs, severe malnutrition (BMI<20Kg/m² ; Albuminemia <32 g/L with normal values of C-reactive protein (CRP); Decrease in weight >5% in 1 month or >7.5% in 3 months), history of major CVD (Myocardial Infarction, Chronic Heart Failure, Stroke), chronic alcohol abuse, known hepatitis B or C infection, pregnant or lactating women, and need to start dialysis.

Withdrawal from the study occurs in the case of severe anemia needing an urgent blood transfusion or non-adherence and withdrawal of consent.

Individual participant data (IPD) often won't be shared with other researchers to protect participants' privacy and confidentiality. Sharing IPD could risk revealing personal information, even if anonymized, which might lead to re-identification. Additionally, there are ethical or legal obligations, informed consent restrictions, and concerns about misuse or misinterpretation of the data that necessitate keeping it restricted.