Tadalafil versus pentoxifylline in the management of diabetic kidney disease: a randomized clinical trial.

Aims: To investigate the efficacy and safety of tadalafil (TAD) versus pentoxifylline (PTX) in the management of diabetic kidney disease (DKD). Some animal studies and clinical trials reported that tadalafil and pentoxifylline have a reducing effect on different blood glucose parameters and lipid profiles which contribute to progress the patients with diabetes mellitus (DM) to DKD.

Methods: From February 2022 to March 2023, 90 patients with type 2 DM and DKD (micro-albuminuria) were enrolled in this randomized-controlled study. The patients were randomized into three equal groups: control group, TAD group, and PTX group. The three groups received traditional blood glucose lowering therapy + ramipril 10 mg PO. The TAD group also received tadalafil 20 mg PO every other day. The PTX group also received pentoxifylline 400 mg PO twice daily.

Results: Both TAD and PTX groups produced statistically significant improvement in the primary outcomes by a significant reduction in Urinary albumin/creatinine ratio (UACR) which was pronounced by a reduction percentage of-47.47%, -53.73% respectively. In addition to a significant decrease in Hemoglobin A1C (HbA) (mmol/mol), Fasting blood glucose (FBG), 2-h postprandial blood glucose (2-h PPG) (p < 0.001). Only the PTX group showed a significant increase in Cr Cl and a significant decrease in S. Cr (p < 0.001). Only the TAD group showed a significant increase in high-density lipoprotein-cholesterol (HDL-C) (p < 0.001), while the PTX group showed a significant decrease in low-density lipoprotein-cholesterol (LDL-C) (p-value 0.011), and triglyceride (p-value 0.002). Both TAD and PTX groups showed a decrease in tumor necrosis factor-α (TNF-α) which was significant only in the PTX group (p < 0.001). There was a significant increase in malondialdehyde (MDA) (p < 0.001), and an increase in urinary neutrophil gelatinase-associated Lipocalin (uNGAL) (p-value 0.850, 0.014 respectively) which was significant only in the PTX group.

Conclusions: The use of tadalafil or pentoxifylline may serve as an effective adjuvant therapy for patients with diabetic kidney disease.

Trial Registration: ClinicalTrials.gov identifier NCT05487755, July 25, 2022.