PGE 1 Treatment of Severe Intermittent Claudication (Short-Term Versus Long-Term, Associated with Exercise)

Abstract

The efficacy, safety, and cost of prostaglandin E1 (PGE1) in the treatment of severe inter mittent claudication was studied comparing a long-term treatment protocol (LTP) with a short-term treatment protocol (STP) in a randomized 20-week study. The study included 980 patients (883 completed the study) with an average total walking distance of 85.5 ±10 m (range 22-119). Phase 1 was a 2-week run-in phase (no treatment) for both protocols. In LTP, phase 2 was the main treatment phase. In the LTP, treatment was performed with 2-hour infusions (60 μg PGE1, 5 days each week for 4 weeks. In phase 3 (4-week interval period) PGE 1 was administered twice a week (same dosage). In phase 4 (monitoring lasting 3 months, from week 9 to 20) no drugs were used. In STP phase 2 treatment was performed in 2 days by a 2-hour infusion (first day: morning 20 μg, afternoon 40 μg; second day morning and afternoon 60 μg). The reduced dosage was used only at the first cycle (week 0) to evaluate tolerability or side effects. Full dosage (60 μg bid) was used for all other cycles. The same cycle was repeated at the beginning of weeks 4, 8, and 12. The observation period was between weeks 12 and 20. A treadmill test was performed at inclusion, at the beginning of each phase, and at the end of 20th week. A similar progressive physical training plan (based on walking) and a reduction in risk factors levels plan was used in both groups. Intention-to-treat analysis indicated an increase in walking distance, which improved at 4 weeks and at 20 weeks in the STP more than in the LTP group. At 4 weeks the variation (increase) in pain-free walking (PFWD) was 167.8% (of the initial value) in the LTP group and 185% in the STP group (p < 0.05). At 4 weeks the variation (increase) in total walking distance (TWD) was 227.6% of the initial value in the LTP group and 289% in the STP group (p < 0.05). At 20 weeks the increase in PFWD was 496% of the initial value in the LTP group vs 643% in the STP group (147% difference; p < 0.02). The increase in TWD was 368% in the LTP group and 529% in the STP group (161% difference; p < 0.02). In both groups there was a significant increase in PFWD and TWD at 4 and 20 weeks, but results obtained with STP are better considering both walking distances. No serious drug-related side effects were observed. Local, mild adverse reactions were seen in 6.3% of the treated subjects in the LTP and 3% in the STP. Average cost of LTP was 6,664 Euro; for STP the average costs was ~ 1,820 E. The cost to achieve an improvement in walking distance of 1 m was 45.8 E with the LTP and 8.5 E with the STP (18% of the LTP cost; p < 0.02). For an average 100% increase in walking distance the LTP cost was 1,989 E vs 421 E with STP (p<0.02). Between-group analysis favors STP considering walking distance and costs. Results indicate good efficacy and tolerability of PGE 1 treatment. With STP less time is spent in infusion and more in the exercise program. STP reduces costs, speeds rehabili tation, and may be easily used in a larger number of nonspecialized units.