(GALE) To Present at American College of Surgeons Clinical Congress 2013

• NeuVax induces a full immune response in treated patients and creates an immune memory to target residual cancer cells
• Phase 3 PRESENT HER2 1+/2+ patients confirmed as optimal treatment population

PORTLAND, Ore., Oct. 7, 2013 — Galena Biopharma (Nasdaq:GALE), a biopharmaceutical company developing and commercializing innovative, targeted oncology treatments that address major unmet medical needs to advance cancer care, today announced an oral presentation given today at the American College of Surgeons Clinical Congress 2013 taking place October 6-10, 2013 in Washington D.C.

The oral presentation, entitled “Predicting Clinical Benefit After Completion of Treatment with the Adjuvant Breast Cancer Vaccine, NeuVax™ (nelipepimut-S or E75),” analyzed biomarker data and clinical outcomes from the NeuVax phase 2 trial. A number of variables were analyzed, including HER2 levels, effect of boosters, induction, and amplification of the NeuVax T-cell response. The data demonstrates that induction, rather than amplification, of an anti-HER2 immune response confers optimal clinical benefit and may partially explain why NeuVax works in HER2 IHC 1+/2+ patients with low-to-intermediate HER2 antigen exposure. This data is consistent with previously published biomarker data indicating a correlation between increasing NeuVax specific T-cells following vaccination and reductions in breast cancer recurrence rates.

“The presentation by Dr. Berry reinforces two key aspects of the NeuVax Phase 3 PRESENT trial. First, the data supports the correlation of the mechanism of action of NeuVax during the induction dosing. Second, immune T-cell response targeting HER2 expressing cancer cells correlates with reduction in recurrences in the target patient population,  and that PRESENT is targeting the patient population with women who have a low-to-intermediate expression of HER2 with an unmet medical need,” said Mark J. Ahn, President and Chief Executive Officer of Galena Biopharma.

NeuVax is a cancer immunotherapy that harnesses the power of the immune system to seek out and destroy HER2 presenting cancer cells. NeuVax is the most immunogenic peptide of the HER2 protein which is injected into the body to allow the immune system to develop a robust HER2-directed T-cell response, creating immune memory, and priming the immune system against tumor cells. This active immunotherapy can not only kill tumor cells present at the time of therapy, but with the additional advantage of immune memory, the boosted immune system is primed to eradicate any remaining or recurrent tumor cells in a patient.

About NeuVax™ (nelipepimut-S)

NeuVax™ (nelipepimut-S) is the immunodominant nonapeptide derived from the extracellular domain of the HER2 protein, a well-established target for therapeutic intervention in breast carcinoma. The nelipepimut sequence stimulates specific CD8+ cytotoxic T lymphocytes (CTLs) following binding to HLA-A2/A3 molecules on antigen presenting cells (APC). These activated specific CTLs recognize, neutralize and destroy, through cell lysis, HER2 expressing cancer cells, including occult cancer cells and micrometastatic foci. The nelipepimut immune response can also generate CTLs to other immunogenic peptides through inter- and intra-antigenic epitope spreading. Based on a successful Phase 2 trial, which achieved its primary endpoint of disease-free survival (DFS), the Food and Drug Administration (FDA) granted NeuVax a Special Protocol Assessment (SPA) for its Phase 3 PRESENT (Prevention of Recurrence in Early-Stage, Node-Positive Breast Cancer with Low to Intermediate HER2 Expression with NeuVax Treatment) study. The PRESENT trial is ongoing and additional information on the study can be found at www.neuvax.com. A randomized, multicenter investigator sponsored, 300 patient Phase 2b clinical trial is also enrolling patients to study NeuVax in combination with Herceptin® (trastuzumab; Genentech/Roche).

According to the National Cancer Institute, over 230,000 women in the U.S. are diagnosed with breast cancer annually. Of these women, only about 25% are HER2 positive (IHC 3+). NeuVax targets the approximately 50%-60% of these women who are HER2 low to intermediate (IHC 1+/2+ or FISH < 2.0) and achieve remission with current standard of care, but have no available HER2-targeted adjuvant treatment options to maintain their disease-free status.

About Galena Biopharma

Galena Biopharma, Inc. (Nasdaq:GALE) is a Portland, Oregon-based biopharmaceutical company developing and commercializing innovative, targeted oncology treatments that address major unmet medical needs to advance cancer care. For more information please visit: www.galenabiopharma.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, statements about the progress of the commercialization of Abstral® and development of Galena’s product candidates, including patient enrollment in our clinical trials, as well as statements about our expectations for our commercial success, plans and prospects. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including those identified under “Risk Factors” in Galena’s Annual Report on Form 10-K for the year ended December 31, 2012 and Quarterly Report on Form 10-Q for the quarter ended June 30, 2013 filed with the SEC. Actual results may differ materially from those contemplated by these forward-looking statements. Galena does not undertake to update any of these forward-looking statements to reflect a change in its views or events or circumstances that occur after the date of this press release.

CONTACT: Remy Bernarda
         Senior Director, Communications
         (503) 405-8258
         rbernarda@galenabiopharma.com