Phase II Clinical Data for Predix’s Lead Drug Candidate Show Positive Results in Generalized Anxiety Disorder; Results Presented at 46th Annual New Clinical Drug Evaluation Unit Meeting Show Efficacy in Anxiety Patients With Minimal Side Effects
Predix Pharmaceuticals, which recently announced a definitive agreement to merge with EPIX Pharmaceuticals (Nasdaq:EPIX), announced today that a Phase II clinical trial of its lead drug candidate, PRX-00023, showed significantly reduced symptoms and was well-tolerated in the 21 patients with generalized anxiety disorder (GAD) participating in the four-week, open-label study. The results are being presented at the 46th Annual New Clinical Drug Evaluation Unit (NCDEU) meeting in Boca Raton, Fla.
Lead investigator Sanjay J. Mathew, M.D., Assistant Professor of Psychiatry at the Mount Sinai School of Medicine, commented, “The Phase II data suggest that PRX-00023 has the potential to meet the significant unmet medical need for a once-daily treatment to relieve anxiety without the troublesome side effects associated with many of the other drugs used to treat this disorder. A Phase III clinical trial is ongoing with PRX-00023, and the results from that study will provide further clinical insight into the efficacy and tolerability of this drug candidate in generalized anxiety.”
The Phase II data, which were reported by the Company last year, showed that the GAD patients enrolled in the study had significantly reduced GAD symptoms from day 1, including the Hamilton Anxiety Rating Scale (HAM-A). Six of the 19 patients (32%) with week 4 evaluations achieved remission criteria based on the HAM-A, and 52% had a 50% or greater reduction in the HAM-A total scale. Patients had a diagnosis of GAD, HAM-A screening scores of 20 or greater when they entered the study, and had stopped taking other medicines for the treatment of anxiety.
“Investigators noted a particularly low drop-out rate for this study in comparison to other studies in generalized anxiety, which may indicate that PRX-00023 is well tolerated,” stated Michael G. Kauffman, president and CEO of Predix. “GAD is a chronic illness, and if we continue to see excellent tolerability in our Phase III studies, then we believe this will be an important differentiator for PRX-00023 in this therapeutic area.”
During the trial, patients initially received placebo for one week, and then were given PRX-00023, a novel non-azapirone 5-HT1A selective agonist. PRX-00023 was administered once daily at 40 mg per day for days 1 through 4, 80 mg for days 5 through 14, and 120 mg for days 15 through 28, and then drug was stopped. There were no serious adverse events reported, no discontinuations due to adverse events, no withdrawal symptoms following the 28 days of dosing, and no reports of ataxia, dizziness, insomnia or sexual dysfunction. Additionally, no significant clinical laboratory, vital sign, or ECG effects were observed.
PRX-00023 is currently being studied in patients with GAD in a Phase III clinical trial. 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.
About PRX-00023
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 G-Protein Coupled Receptors (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 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 four internally-discovered drug candidates into clinical trials and has five 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. In addition to PRX-00023, Predix has three other clinical-stage drug candidates: PRX-03140 for the treatment of Alzheimer’s disease, which is expected to enter Phase IIa later this year; 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; and, PRX-07034, which recently entered a Phase I trial and is expected to be developed for the treatment of obesity and also cognitive impairment associated with Alzheimer’s disease or schizophrenia. Additional information about Predix can be found on the company’s website at www.predixpharm.com.
Additional Information About the Merger And Where To Find It
EPIX has filed a registration statement on Form S-4 with the Securities and Exchange Commission containing a joint proxy statement/prospectus in connection with the proposed merger with Predix. Investors and security holders are advised to read the joint proxy statement/prospectus (including any amendments or supplements thereto) regarding the proposed merger because it contains important information about EPIX, Predix and the proposed transaction and other related matters. The joint proxy statement/prospectus will be sent to stockholders of EPIX and Predix seeking their approval of the proposed transaction. Investors and security holders may obtain a free copy of the joint proxy statement/prospectus and any amendments or supplements thereto and other documents filed by EPIX at the Securities and Exchange Commission’s web site at www.sec.gov. The joint proxy statement/prospectus and such other documents may also be obtained for free by directing such request to EPIX Pharmaceuticals, Inc. 161 First Street, Cambridge, Massachusetts, Attn: Investor Relations, tel: (617) 250-6000; e-mail: ahedison@epixpharma.com or Predix Pharmaceuticals Holdings, Inc., 4 Maguire Road, Lexington, Massachusetts 02421, Attn: Investor Relations, tel: (781) 372-3260; e-mail: investors@predixpharm.com.
EPIX and Predix and their respective directors, executive officers and other members of management and employees may be deemed to be participants in the solicitation of proxies with respect to the adoption of the merger agreement and the transactions associated with the merger. A description of any interests that EPIX and Predix directors and executive officers have in the merger is included in the registration statement containing the proxy statement/prospectus that has been filed with the Securities and Exchange Commission and is available free of charge as indicated above.
Safe Harbor Statement
Certain statements in this news release concerning Predix’s business are considered “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. These statements include, but are not limited to, those relating to the timing and results of future clinical development of PRX-00023, the potential efficacy of PRX-00023 and the expected safety and tolerability of PRX-00023 as compared to other drugs treating anxiety. Any or all of the forward-looking statements in this press release can be affected by inaccurate assumptions Predix might make or by known or unknown risks and uncertainties, including, but not limited to: the early stage of product development; uncertainties as to the future success of ongoing and planned clinical trials; and the unproven safety and efficacy of products under development. Consequently, no forward-looking statement can be guaranteed, and actual results may vary materially. Predix undertakes no obligation to publicly update forward-looking statements, whether because of new information, future events or otherwise, except as required by applicable law.