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are unrelated to treatment with PRT-201. To correct for this uneven distribution, we conducted a non-prespecified analysis of the primary endpoint that excluded patency loss events due to
central stenoses. This analysis demonstrated a significant reduction in the risk of primary unassisted patency loss in the 30 microgram PRT-201 dose group (p=0.04) compared to placebo.
benefit of PRT-201 on primary unassisted patency was most pronounced in the subset of patients undergoing placement of a radiocephalic AVF. The subset analysis of this endpoint for
radiocephalic AVF patients receiving the 30 microgram dose, which was not prespecified, showed a significant increase in median primary unassisted patency of >365 days as compared to
125 days in the placebo group. In addition, we observed beneficial drug effects on additional efficacy endpoints, including unassisted maturation, defined as increased vessel diameter and blood
flow without the need for an intervention such as angioplasty; rate of procedures to restore or maintain AVF patency; secondary patency, defined as abandonment of the AVF and the need for creation of
a new vascular access; use for hemodialysis and hemodynamically significant stenosis, or narrowing of blood vessels.
In April 2013, we held an end of Phase 2 meeting with the United States Food and Drug Administration, or FDA, during which we confirmed elements of our Phase 3 development
plan, including the primary endpoint. We plan to perform two 300-patient Phase 3 trials of PRT-201 using a 30 microgram dose, which will enroll patients undergoing a surgical procedure to
create a radiocephalic AVF. We began enrolling patients in our first Phase 3 clinical trial in the third quarter of 2014, and anticipate that results will be available in the first quarter of
2017. We expect to initiate our second Phase 3 clinical trial in the first half of 2015. In May 2014, following the results from our Phase 2 trial and to fund our first Phase 3
trial, we closed on the $25.0 million first tranche of a $45.0 million total financing. The financing was led by Abingworth, Deerfield and Pharmstandard and included investments from our
existing venture investors. While the FDA offered no assurances that it will not require us to conduct any additional clinical studies, we believe we will not need to conduct any additional clinical
studies after our Phase 3 trials. Further, 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. PRT-201
has received fast track designation which is designed to facilitate the development and expedite the review of drugs to treat serious conditions and fill an unmet medical need, from the FDA and orphan
drug designation in the United States and European Union, for hemodialysis vascular access indications.
believe that if our Phase 3 clinical program is successful PRT-201 will potentially become the standard of care for patients with chronic kidney disease who are undergoing
surgical placement of a radiocephalic AVF. We retain worldwide commercial rights to PRT-201. If approved by regulatory authorities, we intend to commercialize this product in the United States
ourselves with a specialty hospital sales force, focused primarily on vascular surgeons, and intend to seek one or more collaborators to commercialize the product in additional markets. Our patents
include claims covering formulations, methods of manufacturing and use of elastases, providing protection in the United States through mid 2029 and European Union through 2028, with potential
extension through 2032 in the United States and the European Union.
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 are conducting our first Phase 3 clinical trial and plan to conduct our second Phase 3 clinical trial in
radiocephalic AVF placement using a 30 microgram dose of PRT-201, the population and dose in which, in a non-prespecified analysis, we observed an improvement in primary unassisted patency with
PRT-201 in our Phase 2 trial.
- Phase 3 endpoints same as our Phase 2
trial. The primary endpoint in our Phase 3 trials, primary unassisted patency, will be the same as we used in our Phase 2
trial. In addition, our secondary