OXIS and Majority-Held BioCheck Announce Launch of New Research Assays for Biomarkers of Cancer.

SAN FRANCISCO -- New Antibodies and ELISA Test Kits Allow For Precise Measurement of HMGA2 Protein Associated With Some Aggressive Breast Cancers

OXIS International (OTCBB:OXIS) (Nouveau Marche:OXIS) (FWB:OXI) announced today the upcoming launch of new immunoassay products for the oncology research market. The announcement came in San Francisco, CA at the 15th Annual Experimental Biology meeting, a gathering of over 12,000 independent biomedical scientists shaping the current and future clinical advances.

OXIS International is a biopharmaceutical company focused on commercializing research assays, nutraceutical and therapeutic products related to oxidative stress and, through its majority interest in BioCheck, a leading provider of high quality immunoassay clinical kits and contract services.

The new immunoassay (ELISA) test kits and reagent products, expected to be commercially available from OXIS' majority-held BioCheck in May of 2006, are designed to allow researchers to measure the presence and precise concentration levels of the HMGA2 protein in in vitro biological samples. In addition, BioCheck anticipates the commercial launch of new angiogenesis related research products in late summer 2006.

While these products are initially targeted at the oncology research market, the OXIS and BioCheck teams plan to continue to develop the commercial utility of the assays including potential FDA approvals.

According to the American Cancer society, breast cancer was the second (after lung cancer) most frequently diagnosed cancer among women in the US with approximately 270,000 new cases diagnosed and over 40,000 deaths in 2005.

"The HMGA2 protein has been shown to play a role in the control of cell growth, differentiation and tumorigenesis related to breast cancer," stated Dr. John Chen, a biochemist and Founder and President of BioCheck. "We are thrilled to be able to offer cancer researchers new tools that will enable them to advance the understanding of the disease and to help validate potential clinical diagnostic applications of this technology."

"John Chen's thirty plus years of R&D and assay development expertise are tremendous assets to our companies," stated Steve Guillen, CEO and President of OXIS. "John has successfully developed over 50 enzyme immunoassay and rapid tests, including the first early pregnancy test. His technical expertise in immunology and biochemistry is complemented by his ability to facilitate technology transfer from research and development to manufacturing of unique biomarkers."

According to JP Morgan's 2005 estimates, the early stage breast cancer detection market ranges form $325 million to $375 million and is expected to grow 8-10% driven by a growing and aging patient population, propensity for earlier and more frequent diagnostic screening and increasing cancer awareness.

In 2005, BioCheck entered into a development and marketing agreement with Piscataway, NJ based HMGene, Inc. for the development and manufacturing of an ELISA test for the HMGA2 protein. The detection technology for use in both tissue staining and peripheral blood samples have been patented by HMGene and subsequently licensed to BioCheck for the development of rabbit polyclonal and monoclonal anti-HMGA2 antibodies for Western Blot analyses, immunohistochemistry staining and ELISA assays.

About OXIS and BioCheck:

OXIS International, Inc. develops technologies and products to research, diagnose, treat and prevent diseases of oxidative stress associated with damage from free radical and reactive oxygen species. The company holds the rights to three therapeutic classes of compounds in the area of oxidative stress, and has focused commercialization programs in clinical cardiovascular markers, including MPO (myeloperoxidase) and GPx (glutathione peroxidase), as well as a highly potent antioxidant, Ergothioneine, that may be sold over-the-counter (OTC) as a dietary supplement. OXIS has acquired a 51% interest in and has the option to purchase the remaining 49% of BioCheck.

BioCheck, Inc. is a leading provider of high quality enzyme immunoassay research services and products including immunoassay kits for cardiac and tumor markers, infectious diseases, thyroid function, steroids, and fertility hormones. The company operates a 15,000 square-foot, U.S. Food and Drug Administration (FDA) certified cGMP, and ISO device-manufacturing facility in Foster City, California.

More information about OXIS, BioCheck and their products, services as well as current SEC filings may be obtained by visiting http://www.oxisresearch.com and http://www.biocheckinc.com.

The statements in this press release that are not purely historical are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, including, without limitation, statements regarding our expectations, objectives, anticipations, plans, hopes, beliefs, intentions or strategies regarding the future. Factors that could cause actual results to differ materially from the forward-looking statements include risks and uncertainties such as the acquisition of the remaining 49% of the BioCheck shares by OXIS not closing due to, among other reasons, the inability of OXIS to close a financing transaction; the risks inherent in integrating an acquired business; risks inherent in owning a majority interest in a company; unforeseen difficulties in achieving synergies following an acquisition; unforeseen difficulties related to the company's oxidative stress and other diagnostic products; the development by the company's competitors of new competing products; and other risks indicated in the company's filings with the Securities and Exchange Commission. It is important to note that actual outcomes could differ materially from those in such forward-looking statements. Readers should also refer to the documents filed by the company with the Securities and Exchange Commission, specifically the company's annual report on Form 10-K for year ending December 31, 2005 filed with the Securities and Exchange Commission on March 31, 2006.