Pilot Study of PRT-201 Following Angioplasty in Patients With Peripheral Artery Disease (PAD)

Inclusion Criteria:

1. Age of at least 18 years

2. Clinical diagnosis of PAD, secondary to atherosclerosis affecting a lower limb

3. Rutherford classification 2-4 (moderate claudication to ischemic rest pain)

4. ABI <0.90 at rest or with exercise, or a toe-brachial index <0.70, or radiographic
evidence of PAD that correlates with clinical symptoms

5. De novo lesion, not previously treated by angioplasty or atherectomy

6. Greater than 70% stenosis of the SFA or PA, target lesion length of 10 cm or less,
and at least one patent runoff vessel. Short segment occlusions (<10 cm) are
acceptable

7. If female and of childbearing potential (premenopausal and not surgically sterile)
must have a negative pregnancy test at the screening visit and be willing to use
contraception from the time of the screening visit to 1 week following study drug
administration. Acceptable methods of birth control include abstinence, barrier
methods with spermicide, implants, injectables, oral contraceptives, intra-uterine
device, or a vasectomized partner

8. Ability to understand and comply with the requirements of the entire study and
communicate with the study team

9. Ability to provide written informed consent using a document that has been approved
by the required institutional review board

Exclusion Criteria:

1. Previous treatment with PRT-201

2. Patients in whom arterial insufficiency in the lower extremity is the result of an
immunologic or inflammatory non-atherosclerotic disorder (e.g. Buerger's disease,
vasculitis)

3. Current severe critical limb ischemia defined as ulceration or gangrene

4. Planned atherectomy of the arteries of the index leg

5. Prior or planned stenting of the target lesion

6. Prior bypass surgery to the target SFA or PA

7. Severe concentric medial calcification of the target lesion thought to interfere with
drug delivery to the adventitia that is defined subjectively by the Investigator
based on fluoroscopic appearance.

8. History of metastatic cancer

9. Presence of aortic or peripheral artery aneurysm

10. Platelet count <130K, hematocrit <30%, bilirubin or ALT >3.0 times the upper limit of
normal

11. Pregnancy, lactation or plans to become pregnant during the course of the study

12. Presence of any significant medical condition that might significantly confound the
collection of safety and efficacy data in this study

13. Treatment with any investigational drug within the previous 30 days or
investigational antibody therapy within 90 days prior to signing informed consent

14. Known allergy to contrast media