Positive interim results from PROLOR's hGH-CTP Phase II trial in growth hormone deficiency

Apr 11 2011

PROLOR Biotech, Inc. (NYSE Amex: PBTH) today reported positive interim efficacy results from a Phase II clinical trial of its long-acting CTP-modified version of human growth hormone (hGH-CTP) in growth hormone deficient adults.  The interim efficacy data show that a single weekly injection of hGH-CTP, even when administered at relatively low doses, has the potential to replace seven consecutive daily injections of currently marketed human growth hormone (hGH).  These positive interim data follow PROLOR's announcement in February that hGH-CTP has demonstrated a good safety profile in the Phase II trial, as confirmed in a review of interim data by the independent Data and Safety Monitoring Board.

The objective of the randomized open-label, multicenter Phase II trial is to measure the safety and tolerability of hGH-CTP and to assess dose ranging and dose response.  The trial is enrolling up to 56 growth hormone deficient adults allocated among several dosing cohorts.  

The three main cohorts in the trial are receiving a single weekly dose of hGH-CTP, containing 30%, 45% or 100% of the cumulative commercial hGH dose these patients would usually inject each day over the course of seven days (referred to as the "30%, "45%" and "100%" cohorts, respectively.)  The interim efficacy data reflect initial results from 34 patients, all of whom were enrolled in "low-dosing" cohorts.  

In addition to the three main cohorts, PROLOR researchers are also enrolling growth hormone deficient adults in an experimental fourth cohort.  The patients in the experimental fourth cohort are receiving a single injection of hGH-CTP once every two weeks that contains 50% of the cumulative commercial dose of hGH that they would usually inject each day during a two-week period.

Efficacy in the trial for the cohorts receiving a single weekly injection of hGH-CTP is defined by measuring whether these growth hormone deficient adults can maintain insulin-like growth factor 1 (IGF-1) levels within the desired therapeutic range over a period of seven days.  The interim results from the "low-dosing" 30% and 45% cohorts suggest that this efficacy endpoint is achievable -- a single weekly injection of hGH-CTP in growth hormone deficient adults has the potential to maintain IGF-1 levels within this target range for at least seven days, thereby potentially enabling these patients to replace their current regimen of seven consecutive daily injections of hGH with a single injection of hGH-CTP.

"We are very encouraged by these interim results from our hGH-CTP Phase II clinical trial," noted Dr. Avri Havron, CEO of PROLOR.  "They show that single weekly injections of hGH-CTP appear to work well in adults with growth hormone deficiency, even when given at low doses."  

Dr. Havron added, "We expect to complete this Phase II trial around mid-year.  Based on these promising interim data, we are increasingly confident that the Phase II trial will provide sufficient information to enable our researchers to establish the most suitable doses of hGH-CTP for our planned Phase III registration trial in adults with growth hormone deficiency."