(GALE) Initial Folate Binding Protein Vaccine Phase 1 Trial Results Presented

• Folate Binding Protein (FBP) shown to be safe and immunogenic in its Phase 1 trial
• Phase 2a trial expected to initiate by year end

PORTLAND, Ore., Nov. 11, 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 a poster presentation at the Society for Immunotherapy of Cancer (SITC) Conference 2013 on November 7-10, 2013, in National Harbor, Maryland. The data presented are the results of the Phase 1 portion of the trial for the Folate Binding Protein (FBP) vaccine. FBP is a folate receptor alpha-derived, peptide-based cancer immunotherapy administered to HLA A2 positive patients in combination with granulocyte macrophage-colony stimulating factor (GM-CSF) as an adjuvant treatment to prevent recurrences in high-risk, endometrial and ovarian cancer patients rendered disease-free after completing standard of care therapy.

The poster presentation entitled “Phase 1 Trial Results of a Folate Receptor Alpha-directed Cancer Vaccine (E39) in Ovarian and Endometrial Cancer Patients to Prevent Recurrence,” showed that the FBP vaccine is both safe and immunogenic. The primary outcome of the Phase 1 trial was to determine safety and the optimal dose, with a secondary outcome to look for an initial efficacy signal and immunological response. The optimal dose was determined to be 500 mcg peptide combined with 250 mcg GM-CSF. FBP proved to be well tolerated, with largely Grade 1 toxicities, primarily consisting of injection site reactions. After a median follow-up of six months, there have been 2 recurrences (13.3%; n=15) in the vaccine group vs. 4 recurrences (25%, n=16) in the control group, although the trial was not powered for any efficacy measurements.

“New approaches are needed for ovarian and endometrial cancer patients who face a high risk of disease recurrence. The initial results from the Phase 1 trial show that the FBP vaccine may be a potential cancer immunotherapy treatment to prevent recurrence in these high risk patient populations,” concluded Dr. Erika J. Schneble, San Antonio Military Medical Center, San Antonio, TX who presented the results at the SITC conference.

The Phase 1 component was a 3×3, dose-escalation, safety trial enrolling disease-free endometrial and ovarian cancer, HLA-A2 positive patients into the vaccine group, while HLA-A2 negative patients were being followed prospectively as an untreated control group. Six monthly intradermal inoculations of either 100mcg, 500mcg, or 1000mcg of peptide vaccine + 250 mcg GM-CSF immunoadjuvant were administered during the primary vaccine series. Immunologic responses were assessed by both local reaction after each inoculation and by delayed-type hypersensitivity (DTH) reaction measured pre-vaccination and after the primary vaccine series. Recurrences are determined clinically. Thirty-one patients were enrolled in the Phase 1 trial: 15 in the vaccine group and 16 in the active control group. There were no significant differences in age, grade, stage, or nodal status between groups. Overall, the vaccine was well tolerated with the majority of local and systemic toxicities Grade 1 (maximum local toxicity: 93% Grade 1; maximum systemic toxicity: 60% Grade 1). Local skin reactions increased from the first to the third injections, and then plateaued for the remainder of therapy.

“We are encouraged by the initial results of our Phase 1 trial with the FBP vaccine, showing that it is well-tolerated and demonstrated promising immune responses in high risk gynecological cancers,” said Mark J. Ahn, President and Chief Executive Officer of Galena Biopharma. “As a result, we are moving forward with the Phase 2a component which will be initiated by year end and will include the enrollment of additional patients at the optimal dose as well implementing a booster regimen.”

About Folate Binding Protein (FBP)

Folate Binding Protein (FBP) is highly over-expressed in breast, ovarian and endometrial cancers and is a well-validated therapeutic target. FBP is the source of immunogenic peptides that can stimulate cytotoxic T lymphocytes (CTLs) to recognize and destroy presenting FBP-expressing cancer cells. The FBP vaccine consists of the FBP peptide(s) combined with the immune adjuvant, granulocyte macrophage-colony stimulating factor (GM-CSF). Galena’s FBP vaccine is currently in a Phase 1/2 trial in two gynecological cancers: ovarian and endometrial adenocarcinomas.

About Ovarian/Endometrial Cancers

Ovarian cancer occurs in over 22,000 patients per year in the U.S. and is the most lethal gynecologic cancer. Despite the incidence of ovarian cancer being only approximately 20% of that of breast cancer, the number of patients that die from ovarian cancer is nearly 50% of that of breast cancer. Due to the lack of specific symptoms, the majority of ovarian cancer patients are diagnosed at later stages of the disease. These patients have their tumors routinely surgically debulked to minimal residual disease, and then are treated with platinum- and/or taxane-based chemotherapy. While most patients respond to this treatment regimen and become clinically free-of-disease, the majority of these patients will relapse, and once the disease recurs, the treatment options and successes drop dramatically.

Endometrial cancer is the most common gynecologic cancer and occurs in over 46,000 women, with over 8,000 deaths, in the U.S. annually. There are two basic types of endometrial cancer: endometriod and papillary serous. The latter has a much more aggressive clinical course and the majority of these patients will die of this form of the disease.

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 preliminary results Galena’s clinical trials and planned additional trials. 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 September 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