Adding pentoxifylline to losartan therapy for 1.5 years decreases proteinuria significantly in patients with CKD stages 3-5, researchers concluded.
Shuei-Liong Lin, MD, PhD, and colleagues at the National Taiwan University Hospital in Taipei, studied 56 patients with an estimated glomerular filtration rate (eGFR) of 10-60 mL/min/1.73 m2 and proteinuria (urine protein-to-creatinine ratio greater than 500 mg/g).
The study was conducted in two stages. In the first stage, which lasted 12 months, patients were randomly assigned to one of two groups. Group 1 included 27 patients who received losartan alone and served as controls. Group 2 included 29 patients who received pentoxifylline—a nonselective phosphodiesterase inhibitor that exerts potent inhibitory effects against cell proliferation—in addition to losartan.
In the second stage, which lasted six months, both groups received pentoxifylline. At baseline, groups 1 and 2 had a mean eGFR of 38.9 and 41.1, respectively.
In the first stage, pentoxifylline decreased median proteinuria from 1,140 to 800 mg/g (a median decrease of 23.9%) compared with a median proteinuria increase from 1,410 to 1,810 mg/g (a median increase of 13.8%) in the control group, the researchers reported in the American Journal of Kidney Diseases (2008;52:464-474).
The difference between the groups was 38.7%. In the second stage, pentoxifylline reproduced the proteinuria-reducing benefit in the control group.
The researchers said their data indicate that the decrease in proteinuria associated with pentoxifylline is related to suppression of renal tumor necrosis factor-α and monocyte chemoattractant protein 1 excretion, substances that have an important role in kidney disease progression.