Perspective:

The following are 10 points to remember about clinical trials in peripheral vascular disease (PVD):

1. Tremendous advances have occurred in therapies for PVD; however, until recently, it has not been possible to examine the entire clinical trial portfolio of studies for treatment of PVD (both arterial and venous disease).

2. A search of the interventional trials registered in ClinicalTrials.gov from October 2007 through September 2010 (n = 40,970) identified 676 (1.7%) PVD trials (n = 493 arterial only, n = 170 venous only, n = 13 both arterial and venous).

3. PVD studies represent a small group of trials registered in ClinicalTrials.gov, despite the high prevalence of vascular disease in the general population.

4. There remains significant geographic variation in access to trials within the United States. Within the United States, access to PVD trials is largely limited to major metropolitan areas, which tend to be the usual locations of larger medical centers and universities.

5. Future efforts may need to target policy to define and ensure appropriate representation of US patients within trials, given that therapies may have different efficacy in different populations.

6. There is also discordance between the large percentage of registered trials in the current portfolio examining device therapies for PAD, as opposed to behavioral modification/interventional therapies (trials that include the following type of interventions: psychotherapy, lifestyle counseling/modification [walking/exercise, educational workshops, or educational printed materials], and physical therapy).

7. Given the high cost of development and subsequent trials, particularly among devices and biologics, novel approaches to trial designs will be needed. One potential solution to these gaps includes partnering academia with industry to design new registries or leverage existing registries to answer questions of efficacy at lower operational costs than with traditional trials.

8. Given rising health care costs, a cost-effectiveness approach that includes quality-of-life assessment of novel therapies (primarily devices and genetics) will be required to justify their costs.

9. There is a limited footprint of nonindustry funding sources in the PAD arena. This suggests that the majority of trials are done by industry to support registration and marketing.

10. Future investigator-initiated, multicenter trials and comparative effectiveness studies are indicated to address and compare the effectiveness of noninterventional (medical, exercise) and interventional therapies (endovascular and surgical) for treatment of claudication and effectiveness of surgery versus angioplasty/stenting as revascularization strategies for intermittent claudication or critical limb ischemia treatment.