6.1.2008 - ASCO: First-In-Man Study of RTA 402 Yields Promising Results in Patients with Advanced Cancers

IRVING, TX -- June 1, 2008-- Reata Pharmaceuticals, Inc. announced results from a first-in-man study of RTA 402 in patients with advanced cancers, presented in an oral session at the annual meeting of the American Society for Clinical Oncology.  RTA 402 is the clinical lead from Reata's Antioxidant Inflammation Modulators (AIMs), a new and highly promising category of drugs for the treatment of cancer and inflammation.  One of the study's Principal Investigators, Dr. David Hong from the University of Texas M. D. Anderson Cancer Center, presented data showing that RTA 402 had an excellent safety profile and provided a clinical benefit in a significant percentage of patients.  Investigators also confirmed that the drug was active against its biological targets, NF-kappa B and STAT3.  These pro-inflammatory transcription factors promote tumor growth, angiogenesis, invasion, metastasis, and resistance to therapy.  Overall, RTA 402 showed a profile of disease control and tumor reduction comparable or superior to any recently approved targeted therapy in a Phase I patient population and a markedly superior side effect profile.

"We are very excited about the anti-cancer results seen with RTA 402, both in the Phase 1 study presented today and in our ongoing study in pancreatic cancer," commented Warren Huff, Reata Chief Executive Officer.  "The AIMs are on track to become important new targeted cancer therapies with a highly differentiated profile based on their novel biology and outstanding safety profile. We see the potential for RTA 402 to be incorporated into front-line regimens for the treatment of solid tumors and lymphoid malignancies."

Novel Mechanism of the AIMs

RTA 402 is the clinical lead from a portfolio of AIMs being developed by Reata. These drugs suppress key inflammatory signaling pathways that promote tumor growth and progression.  RTA 402 inhibits the activity of NF-kappa B and STAT3, transcription factors that are chronically activated in many cancers and control the expression of many genes involved in inflammation and immune response.  Consequently RTA 402 inhibits the tumor's ability to grow, promote the formation of new blood vessels (known as "angiogenesis"), invade surrounding tissues, and spread to other parts of the body (known as "metastasis").  Additionally, STAT3 is believed to play a critical role in allowing tumors to evade detection and destruction by the immune system.  Preclinical studies with RTA 402 have shown that inhibiting STAT3 may allow the body to mount an anti-tumor immune response.  RTA 402 is the only anti-cancer agent with this mechanism currently in clinical development.

RTA 402 Study Results

As is standard in the development of cancer drugs, this first-in-man study was conducted in patients with advanced cancers without other treatment options.  In this difficult patient population, RTA 402 provided a clinical benefit of tumor regression or stable disease to almost half of the evaluable patients in the study.  Two patients, one with mantle cell lymphoma and one with thyroid cancer, experienced "Objective Responses" in which their tumors disappeared or shrank significantly following treatment.  Additionally, several patients with refractory, rapidly-growing melanoma or renal cell carcinoma saw their tumors stop growing for more than six months.  The activity seen with RTA 402 in this study compares favorably with Phase 1 studies of recently approved, targeted anti-cancer agents.  Additional data from the study suggest that RTA 402 treatment may promote an anti-tumor immune response.  Current research by Reata and its collaborators is focused on characterizing these effects in detail.

RTA 402 was exceptionally well tolerated, with a significantly better side effect profile than recently approved agents.  Some patients experienced tolerable nausea and fatigue, which is consistent with agents that stimulate an anti-tumor immune response.  More than 90% of the patients in this study had no drug-related side effects greater than grade 2.  With this safety profile, the drug is an excellent candidate for use in combination therapy with other types of cancer therapies, particularly first-line regimens. 

RTA 402 is currently being tested in a Phase 1/2 clinical study, in combination with standard therapy, in patients with pancreatic cancer.  Multiple Objective Responses have been seen in initial dose cohorts, which is extremely promising in this very aggressive type of cancer.  Reata expects to report further pancreatic cancer results in early 2009.  Combination therapy trials in other forms of cancer are planned.

About Reata

Reata Pharmaceuticals, Inc. is a biopharmaceutical company focused on translating innovative science into breakthrough medicines.  The company's two lead programs are in advanced clinical trials for deadly, late-stage cancers and proof of concept studies in inflammatory diseases.  In parallel with its clinical development, Reata is advancing a breakthrough drug discovery platform using protein misfolding, identified as a key factor in cancer and neurodegenerative disease, to feed its pipeline of small molecule therapeutic candidates. Reata takes a new and different approach to biotechnology, managing its pipeline as a portfolio of opportunities that can be advanced on a single management and physical infrastructure, streamlining the route to human trials and approval.   For more information, visit www.reatapharma.com.

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