PROLOR Biotech announces initiation of hGH-CTP Phase III trial in growth hormone deficient adults

PROLOR Biotech, Inc. (NYSE Mkt: PBTH), a company developing next-generation biobetter therapeutic proteins, today announced the initiation of a pivotal Phase III clinical trial of hGH-CTP, the company's proprietary version of human growth hormone (hGH), in growth hormone deficient adults.

PROLOR is developing hGH-CTP to provide growth hormone deficient adults and children with hGH therapy that may require only once-weekly or bi-monthly injections, rather than the daily injections required by current hGH therapy. The initiation of the Phase III clinical trial follows a set of successful Phase II trials showing that hGH-CTP has the potential to be effective when injected once weekly. In these studies, hGH-CTP was shown to be well tolerated and safe, and it met all clinical endpoints.

The hGH-CTP Phase III trial is a randomized, placebo-controlled study to evaluate the efficacy and safety of hGH-CTP injected weekly in adults with growth hormone deficiency. The primary endpoint is defined as the change in truncal fat mass from baseline to six months after initiation of treatment. The trial is being conducted at clinical centers in the U.S., Europe and Israel.  

Following regulatory review of the hGH-CTP Phase II data, PROLOR obtained clearance to use a pivotal Phase III trial design that includes a six-month assessment of efficacy and safety, followed by a subsequent six-month period of safety assessment. PROLOR's previous estimate and guidance had noted that a 12-month period of subsequent safety assessment might be required. This reduction of six months in the length of the required safety assessment and resulting reduction in the overall trial duration may enable PROLOR to submit an application for hGH-CTP marketing approval sooner than previously anticipated, subject to successful completion of the Phase III trial. 

In the U.S., the Food and Drug Administration (FDA) has confirmed that the regulatory pathway for hGH-CTP is via a Biologics License Application (BLA), which would be submitted subject to the successful completion of the Phase III trial. The BLA pathway provides the manufacturer with 12 years of data exclusivity in the U.S., starting at the time of FDA approval.   

"In all studies to date, hGH-CTP has demonstrated excellent safety and the potential for once-weekly administration," said Abraham Havron, Ph.D., CEO of PROLOR. "We are delighted now to initiate our pivotal Phase lll trial designed to provide the definitive data needed to apply for marketing approval in the U.S. and Europe."

Dr. Havron continued, "We are encouraged by our receipt of regulatory clearance to use a six-month safety tracking period in the trial, instead of our anticipated 12 months. This could potentially enable us to accelerate the timeline for filing for marketing approval and may allow PROLOR to launch hGH-CTP sooner than originally anticipated. In addition, we are pleased with the FDA's confirmation of the BLA submission pathway for hGH-CTP, which provides for 12 years of data exclusivity in the U.S., effectively adding another layer of potential protection from generic and biosimilar competition."

Update on Status of PROLOR Merger with OPKO Health
Separately, PROLOR today announced the expiration of the 40-day "go-shop" period pursuant to the terms of its definitive merger agreement with OPKO Health, Inc. (NYSE: OPK).  On April 24, 2013, OPKO Health and PROLOR Biotech announced that the companies had signed a definitive merger agreement under which OPKO will acquire PROLOR in an all-stock transaction.  Under the terms of the agreement, which has been approved by the boards of directors of both companies, holders of PROLOR common stock will receive 0.9951 shares of OPKO common stock for each share of PROLOR stock.  Under the terms of the agreement, PROLOR and its representatives had the right to solicit, encourage, facilitate and engage in discussions and negotiations with third parties with respect to competing proposals until 11:59 p.m. EDT, on June 2, 2013.  PROLOR did not receive any competing proposals during the "go-shop" period.  PROLOR and OPKO expect the transaction to be completed during the second half of 2013.  Closing of the transaction is subject to certain conditions, including the approval of the merger agreement by PROLOR's stockholders, approval of the issuance of the share consideration by OPKO's stockholders, the receipt of antitrust approval and other customary closing conditions.