A comparison of cilostazol and pentoxifylline for treating intermittent claudication.
OBJECTIVE
We performed a randomized, double-blind, placebo-controlled, multicenter trial to evaluate the relative efficacy and safety of cilostazol and pentoxifylline.


METHODS
We enrolled patients with moderate-to-severe claudication from 54 outpatient vascular clinics, including sites at Air Force, Veterans Affairs, tertiary care, and university medical centers in the United States. Of 922 consenting patients, 698 met the inclusion criteria and were randomly assigned to blinded treatment with either cilostazol (100 mg orally twice a day), pentoxifylline (400 mg orally 3 times a day), or placebo. We measured maximal walking distance with constant-speed, variable-grade treadmill testing at baseline and at 4, 8, 12, 16, 20, and 24 weeks.


RESULTS
Mean maximal walking distance of cilostazol-treated patients (n = 227) was significantly greater at every postbaseline visit compared with patients who received pentoxifylline (n = 232) or placebo (n = 239). After 24 weeks of treatment, mean maximal walking distance increased by a mean of 107 m (a mean percent increase of 54% from baseline) in the cilostazol group, significantly more than the 64-m improvement (a 30% mean percent increase) with pentoxifylline (P <0.001). The improvement with pentoxifylline was similar (P = 0.82) to that in the placebo group (65 m, a 34% mean percent increase). Deaths and serious adverse event rates were similar in each group. Side effects (including headache, palpitations, and diarrhea) were more common in the cilostazol-treated patients, but withdrawal rates were similar in the cilostazol (16%) and pentoxifylline (19%) groups.


CONCLUSIONS
Cilostazol was significantly better than pentoxifylline or placebo for increasing walking distances in patients with intermittent claudication, but was associated with a greater frequency of minor side effects. Pentoxifylline and placebo had similar effects.
Dawson
D L
DL
Wilford Hall Medical Center, Lackland AFB, Texas, USA.
Cutler
B S
BS
Hiatt
W R
WR
Hobson
R W
RW
Martin
J D
JD
Bortey
E B
EB
Forbes
W P
WP
Strandness
D E
DE
D000368:Aged; D000077407:Cilostazol; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005080:Exercise Test; D005260:Female; D006801:Humans; D007383:Intermittent Claudication / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010431:Pentoxifylline / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D012720:Severity of Illness Index; D013777:Tetrazoles / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D016138:Walking
D013777:Tetrazoles; D014665:Vasodilator Agents; D000077407:Cilostazol; D010431:Pentoxifylline