The Phase 3 trials will use the same primary endpoint, primary unassisted patency over 12 months, used in our Phase 2 trial. In our end of
Phase 2 meeting with the FDA, the FDA agreed that primary unassisted patency could be used as the primary endpoint. Our secondary endpoint, secondary patency over 12 months, and tertiary
endpoints, unassisted maturation, use for hemodialysis and average procedure rates, in our Phase 3 trials were all endpoints in our Phase 2 trial.
began enrolling patients in our first 300 patient Phase 3 clinical trial in the third quarter of 2014, and anticipate that results will be available in 2017. This
Phase 3 clinical trial will include two groups, one receiving PRT-201 (n=200) and the other receiving placebo (n=100). We expect to initiate the second, substantially similar, Phase 3
clinical trial in the first half of 2015. If the results of the first Phase 3 trial are sufficiently compelling, we intend to meet with the FDA to discuss the possibility of submitting a
Biologics License Application, or BLA, supported by the single Phase 3 trial and may decide to submit a BLA to the FDA prior to completing the second Phase 3 trial.
Additional PRT-201 Indications
We believe that PRT-201 has potential benefits for hemodialysis patients undergoing other types of vascular access procedures. In 2013,
we completed a successful Phase 1/2 trial in patients undergoing surgical placement of an arteriovenous graft, or AVG, which is a synthetic tube a surgeon uses to connect a vein and an artery. We may
develop PRT-201 for additional hemodialysis indications including AVGs or brachiocephalic AVFs.
believe PRT-201 also has the potential to treat a number of renal and vascular diseases for which therapeutic options are limited. We are currently enrolling patients with symptomatic
peripheral artery disease, or PAD, in a Phase 1 dose-escalation trial in which patients are treated with PRT-201 via a drug delivery catheter following balloon angioplasty.
We estimate approximately 130,000 AVFs are created in the United States annually, of which 40% are radiocephalic. We believe that the
number of radiocephalic AVFs created annually may rise significantly if PRT-201 gains FDA approval, as this would allow surgeons to place radiocephalic AVFs in patients that they previously considered
at an unacceptably high risk of AVF failure.
approved, PRT-201 will be administered primarily by vascular surgeons, who we believe are acutely aware of the clinical need and are receptive to new therapies. We believe PRT-201
will be reimbursed appropriately as costs related to AVF surgical placement, which is typically performed in the hospital outpatient setting, are not included in the ESRD bundle, the single bundled
payment from Medicare for a number of the costs of hemodialysis treatments, medications, labs and supplies for patients with end stage renal disease. We believe that PRT-201 adoption will be supported
by key stakeholders, including referring nephrologists, patient advocacy groups, large dialysis organizations and payors. We plan to target our marketing and sales efforts to vascular surgeons who
create AVFs. There are
approximately 2,800 vascular surgeons in the United States. We believe a specialty hospital sales force of approximately 75-100 representatives will enable us to call on the approximately 1,300
hospitals that account for more than 90% of the AVF surgical placements performed in the United States annually.
We believe our company and PRT-201 possess the following attributes that increase the likelihood that we will be successful in
developing and commercializing PRT-201:
- Entering Phase 3 trials for radiocephalic AVF
placement. We plan to conduct our Phase 3 clinical trials in radiocephalic AVFs using a 30 microgram dose of PRT-201, the
population and dose in