Positive Phase II Clinical Trial Results with HER2/neu Vaccine.

SAN ANTONIO -- COL George E. Peoples, M.D. presented positive clinical results from a HER2/neu vaccine based on an immunogenic peptide called E75 developed for the immunotherapy of breast cancer and other HER2/neu-expressing cancers. The clinical update was presented at the 2006 San Antonio Breast Cancer Symposium by Dr. Peoples, Director, Cancer Vaccine Development Lab, Uniformed Services University of the Health Sciences, Bethesda, Md. (USU).

COL Peoples, now Chief of Surgical Oncology at Brooke Army Medical Center in San Antonio, received his medical degree from Johns Hopkins, completed a surgical residency at Harvard's Brigham & Women's Hospital, completed a fellowship at The University of Texas M. D. Anderson Cancer Center (UTMDACC), and was Chief of Surgical Oncology at Walter Reed Army Medical Center for several years prior to assuming his current position. He is widely published in the area of peptide-based cancer vaccines in journals that include Cancer, Proceedings of the National Academy of Sciences, Journal of Clinical Oncology, and Clinical Cancer Research. He has received several million dollars in grants and has been the principal investigator in more than 15 vaccine and immunotherapy clinical trials.

About the Study

E75 is an immunogenic peptide discovered at UTMDACC and derived from the HER2/neu protein which is over-expressed in many breast cancer (BCa) patients. E75 is administered as a vaccine consisting of the peptide mixed with GM-CSF (sargramostim or Leukine([R])) as an immunoadjuvant and administered intradermally on a monthly basis for six months. Two parallel trials of E75 for the prevention of breast cancer recurrence have been conducted. Patients with node positive (NP) BCa have been enrolled in a study to determine vaccine safety, while node negative (NN) patients have been enrolled in a study for dose optimization. All patients underwent standard surgical and medical treatment and are rendered disease-free prior to enrollment. Immunologic response is monitored using in vitro functional assays as well as in vivo DTH responses. Clinical recurrence rates in both trials have been followed closely.

A total of 171 patients have been enrolled thus far in both studies with 90 in the NP trial and 81 in the NN trial. Following enrollment, patients are HLA typed; A2 and A3 positive patients are then placed in the vaccine arm while all other HLA types are placed in the observation arm. A total of 90 patients have received the vaccine while 81 are in the observation arm of the study. Toxicity has been minimal with local reactions being 86% Grade I and 14% Grade II. Systemic toxicity has been only 16% Grade 0, 70% Grade I, 13% Grade II, and 1% Grade III and mainly attributable to the GM-CSF. All vaccinated patients have demonstrated in vivo immunologic responses as well as in vivo DTH responses post-vaccination though variable. At this point, clinical recurrence rates at 24 months are 5.6% (5/90) for vaccinated patients versus 14.8% (12/81) for the observation group (p=0.04).

Future Development

Based on the advanced development stage of this product and the promising Phase I and Phase II results, Apthera, Inc. has exclusively licensed E75 from UTMDACC and The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc. (HJF). USU, an institution of higher education within the United States Department of Defense and HJF, a non-profit Maryland corporation, operate a Joint Office of Technology Transfer. Additionally, Apthera is establishing a Cooperative Research and Development Agreement with HJF/USU to continue working with Dr. Peoples for the further development of E75 and other promising vaccines.

About Apthera, Inc.

Apthera, Inc. is a private company established in July 2005 to develop and commercialize advanced-stage clinical programs in cancer immunotherapy licensed from renowned academic institutions. Apthera's initial focus is on funding and completing the final phases of development of E75 (now called NeuVax[TM]). Apthera's licensed technology is based on the use of single immunostimulatory peptides, such as E75, and peptide combinations to activate multiple "killer" T-cell clones against multiple tumor antigen epitopes. This new adjunct therapy, in a clinical setting of minimal residual disease, will result in less disease recurrence and improved long-term cancer survival. Apthera has patents and strong proprietary protection on the naturally presented human leukocyte antigen (HLA) peptides, methods of use, compositions, modifications, and processes. The Company's lead product, NeuVax[TM] is being readied for Phase III studies and indicated for the adjuvant treatment of breast and prostate cancers, and other HER2/neu-expressing tumors. Based upon the early success achieved in the clinic, the company now plans an end-of-Phase II meeting with FDA to discuss a Special Protocol Assessment (SPA) and the design and conduct a large, randomized, pivotal Phase III registration study for the breast cancer indication. To learn more about Apthera, please visit http://www.apthera.com.

From the President

Dr. Joseph Sinkule, President and CEO of Apthera commented, "Dr. Peoples has presented a positive, landmark study in the field of cancer vaccines and immunotherapies. The combined results obtained in these controlled studies are truly exciting." NeuVax[TM] can be administered safely and with very minimal toxicity. Both in vitro functional assays and in vivo DTH responses indicate a sustained immunologic response to the vaccine. NeuVax[TM] appears to significantly reduce the rate of recurrence in conventionally treated breast cancer patients. "We believe that this vaccine may represent a new, safe and useful adjunct to current standard therapy in reducing the rate of breast cancer recurrence. We are pleased to be planning the continuation of Phase III and commercial development of this product for breast cancer and other cancer indications, such as prostate cancer, ovarian cancer, and lung cancer."

This news release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements are not historical facts and are subject to risks and uncertainties which could cause actual results and the timing of certain events to differ materially from those set forth in or implied herein including, without limitation, risks associated with clinical development, regulatory approvals, product commercialization, intellectual property claims litigation and other risks associated with the Company's proposed activities.