Predix Pharmaceuticals Achieves Full Enrollment for Phase III Clinical Trial of PRX-00023 in Generalized Anxiety Disorder; Company Expects Preliminary Efficacy, Safety, and Tolerability Data to be Available in Second Half of 2006
Last Update: 7:00 AM ET May 24, 2006
LEXINGTON, Mass. & RAMAT GAN, Israel, May 24, 2006 (BUSINESS WIRE) -- Predix Pharmaceuticals Holdings, Inc., which recently announced a definitive agreement to merge with EPIX Pharmaceuticals, Inc. (EPIX : EPIX Medical Inc
) , announced today that it has completed enrollment for its first Phase III trial of PRX-00023, the company's novel, long-acting 5-HT1A agonist, in patients with generalized anxiety disorder (GAD). This trial is the first of at least two pivotal trials expected in GAD.
"Our plan for this Phase III trial was to conclude the recruitment process by the end of June, and we have accomplished this milestone ahead of schedule. We believe that the rapid enrollment into this study illustrates the interest by both patients and physicians in new, well tolerated agents to treat anxiety. Based on our success with the enrollment for this trial, we continue to expect to provide preliminary Phase III data later this year," said Michael G. Kauffman, M.D., Ph.D., president and CEO of Predix Pharmaceuticals. "We look forward to updating the market and the clinical community once we have the data from this Phase III trial in hand."
Phase III Study Design
The Phase III trial is an eight-week, double-blind, placebo-controlled, multi-center study. The trial includes 25 sites in the United States and has enrolled approximately 310 patients with moderate-to-severe GAD randomized equally into one of two arms: a placebo arm, or a PRX-00023 treatment arm, in which patients receive a dose of 40 mg once daily for three days followed by 80 mg once daily for the remainder of the study. The primary objectives in this trial are to evaluate the efficacy of PRX-00023 in GAD as measured by the change from baseline in the HAM-A scale, and to assess the safety and tolerability of PRX-00023 during treatment of patients with GAD. The HAM-A scale is the FDA accepted standard for the evaluation of anti-anxiety activity, and it is used in all pivotal trials of drug candidates for the treatment of GAD. This trial will be the first of at least two pivotal trials with PRX-00023 for the treatment of GAD.
PRX-00023 is Predix's lead drug candidate and represents a novel, highly selective, non-azapirone class of 5-HT1A agonists discovered using the company's proprietary GPCR modeling, screening and lead optimization technology. Buspirone is currently the only 5-HT1A agonist approved in the United States for the treatment of anxiety, but is taken three times a day, requires approximately three to four weeks of dose adjustment to reach therapeutic levels, and may cause lightheadedness, nausea, headache and restlessness. Several other 5-HT1A agonists have shown efficacy in Phase II and III clinical trials in depression. However, most of these drugs belong to a chemical class of drugs called azapirones, and their development has been hindered by poor tolerability at therapeutic doses, need for dosing up to three times daily, and by the requirement of gradual dose escalation to effective doses because of side effects such as nausea, dizziness, and restlessness which are thought to be caused by azapirones binding to non-5-HT1A G-Protein Coupled Receptors (GPCRs).
In contrast, PRX-00023 is designed to have minimal affinity for the GPCRs believed to be associated with the side effects of 5-HT1A agonists that are in the azapirone chemical class, and to have a more convenient dosing profile than azapirones. PRX-00023 has a half-life of 12 hours, allowing it to be administered once daily.
The Journal of Medicinal Chemistry, the official peer-reviewed journal of the American Chemical Society, recently published a paper highlighting PRX-00023's novel discovery process as illustrative of a new paradigm in drug discovery utilizing in silico methods together with medicinal chemistry that resulted in a substantially reduced discovery timeline for this drug candidate.
About Predix Pharmaceuticals Holdings, Inc.
Predix, based in Lexington, MA, is a pharmaceutical company focused on the discovery and development of novel, highly selective, small-molecule drugs that target G-Protein Coupled Receptors (GPCRs) and ion channels. Using its proprietary drug discovery technology and approach, Predix has advanced three internally discovered drug candidates into clinical trials and has six additional programs in preclinical development and discovery. Predix is expected to complete the first of at least two pivotal Phase III clinical trials for generalized anxiety disorder for its lead drug candidate, PRX-00023, in the second half of 2006. Predix has two other clinical-stage drug candidates: PRX-03140 for the treatment of Alzheimer's disease, which is expected to enter Phase IIa later this year; and, PRX-08066 for the treatment of pulmonary hypertension (PH) and PH associated with chronic obstructive pulmonary disease, which recently completed a Phase Ib trial and is expected to enter Phase IIa in mid-2006. Additional information about Predix can be found on the company's website at www.predixpharm.com.