A randomized controlled trial evaluating the impact of curcumin versus pentoxifylline on patients with chronic kidney disease

Abstract Background Chronic kidney disease (CKD) is a long-term, progressive disorder marked by a steady decline in renal function. It is frequently associated with complications such as anemia, bone and mineral imbalances, oxidative stress, and systemic inflammation. The buildup of uremic toxins, particularly p-cresyl sulfate (pCS), increases cardiovascular risk and mortality. Early diagnosis and timely treatment are essential to slow disease progression and enhance quality of life. This study investigates the nephroprotective roles of curcumin (–) and pentoxifylline (PTX) as adjunctive therapies alongside standard CKD management. Ninety-four CKD patients were randomized into three groups: control (standard care), – (500 mg twice daily), and PTX (400 mg twice daily) for 6 months. Renal function, electrolytes, and quality of life (KDQOL-SF™ v1.3) were assessed at baseline, 1, 3, and 6 months, while biomarkers (pCS, MDA, and Hs-CRP) were measured at baseline and after 6 months. Results After 6 months, – significantly reduced pCS (5.79 ± 3.74 to 5.02 ± 3.41 μg/mL, p = 0.011) and MDA levels (11.26 ± 7.37 to 10.43 ± 8.84 nmol/mL, p = 0.016), while the PTX group showed significant improvement in Hs-CRP levels (7.13 ± 3.53 to 5.52 ± 3.43 mg/L, p = 0.019) and albuminuria (p = 0.034 of ACR). Both treatments favorably affected creatinine, urea, and eGFR compared with control. After 6 months, serum creatinine showed improvement in both intervention groups, decreasing (3.58 ± 2.21 to 3.12 ± 2.18 mg/dL) in the – group and (2.75 ± 1.48 to 2.34 ± 1.17 mg/dL) in the PTX group (both p < 0.001), BUN significantly decreased (41.03 ± 18.38 to 29.96 ± 13.46 mg/dL) and (35.29 ± 12.94 to 28.50 ± 14.59 mg/dL), respectively, compared with worsening values in the control group (both p < 0.001) and eGFR increased (23.77 ± 13.35 to 28.50 ± 15.93 mL/min/1.73m 2 ) and (30.29 ± 14.07 to 35.57 ± 15.40 mL/min/1.73m 2 ), respectively (both p < 0.001). Only mild gastrointestinal side effects were reported across all study groups, with no statistically significant differences between groups and no serious adverse events observed. Conclusions – and PTX treatment may provide adjunctive benefits in CKD by improving selected secondary outcomes related to oxidative stress, inflammation, and renal function. Clinical trial registration This study was retrospectively registered on ClinicalTrials.gov on June 12, 2024 (Identifier: NCT06458465 ) on https://clinicaltrials.gov/study/NCT06458465 .