Galena Biopharma Presents GALE-301/GALE-302 Phase 1b Data at the American College of Surgeons Clinical Congress 2016

SAN RAMON, Calif., Oct. 20, 2016 -- Galena Biopharma, Inc. (NASDAQ:GALE), a biopharmaceutical company committed to the development and commercialization of hematology and oncology therapeutics that address unmet medical needs, today announced that Dr. Doreen Jackson delivered a podium presentation on Galena’s GALE-301 and GALE-302 clinical program at the American College of Surgeons Clinical Congress 2016 in Washington, D.C.  GALE-301 (E39) and GALE-302 (E39’ – variant of E39) are cancer immunotherapies that consist of a peptide derived from Folate Binding Protein (FBP) combined with the immune adjuvant, granulocyte macrophage-colony stimulating factor (GM-CSF) for the prevention of cancer recurrence in the adjuvant setting.  The Phase 1b is a single-center, randomized, single-blinded, three-arm study in patients with breast or ovarian cancer diagnosis who were treated with standard of care and were without evidence of disease. This trial augments the Phase 1/2a trial with single-agent GALE-301 in ovarian and endometrial cancers.

The presentation is entitled, “A Phase Ib Trial Comparing Different Doses/Schedules of a Folate Binding Protein (FBP)-derived Peptide Vaccine, E39, and its Attenuated Version, E39’, to Induce Long-term FBP-specific Immunity in Disease-free Cancer Patients.” In this trial, which enrolled mostly breast cancer patients, who have lower FBP exposure than ovarian patients, the 500mcg dose appears to provide a more optimal immunological response.  This differs from the results in ovarian cancer patients, who have much higher FBP expression, with potential secondary immune tolerance, where 1000mcg was the optimal dose. However, E39’ (GALE-302) given after E39 (GALE-301) was able to induce long-term immunity in both dosing cohorts, underscoring the potential importance of attenuated peptides in relatively antigen-naïve patients.

In the patients who received 500mcg of peptide (n=14), delayed-type hypersensitivity (DTH), but not E39-specific cytotoxic T-lymphocytes (CTLs), increased at 1- and 6-months post-primary vaccine series (PVS)(p=0.03 for both).  No differences were seen in the patients (n=16) who received 1000mcg of peptide.  Comparing the 3 arms in patients who received 500 mcg dosing, only the patients who received E39 followed by E39’ showed increased DTH at 1-month (p=0.013) and 6-months (p<0.0001).  In the patients with this same schedule who received 1000mcg of peptide, at 6-months they saw increased DTH (p=0.02) and CTLs (p=0.046).  There were no clinicopathologic differences or toxicities greater than grade 2 seen in any of the doses or schedules.

“Similar to the FBP expression levels presented earlier this month from the GALE-301 clinical trial, this GALE-301/GALE-302 data on dosing and treatment schedules is extremely valuable as it highlights the potential utility of the vaccine in different cancer indications as we plan the next path forward for our clinical program targeting FBP,” said Bijan Nejadnik, M.D., Executive Vice President and Chief Medical Officer. “This data adds to the body of science for the vaccine and is instrumental in understanding the interaction of our peptides in the treatment landscape. Importantly, the immunologically active doses of the vaccine targeting FBP seem to vary between the breast and ovarian patient populations, and may reflect the implication of the level of FBP expression on the cells. We may consider the use of an attenuated version of this peptide in patient populations with lower FBP expression, since the potency of the FBP vaccine could lead to T-cell burn-out in patients over time.”

Dr. Nejadnik continued, “We would like to congratulate Dr. Jackson who was given an award for ‘Excellence in Research’ by the American College of Surgeons for her work on this program.  And, we look forward to her poster presentation in December at the San Antonio Breast Cancer Symposium where she will be providing additional data from this trial in breast cancer patients.”

HLA-A2-positive breast or ovarian cancer patients were enrolled after completion of standard of care and without evidence of disease, regardless of FBP expression level. The PVS includes six inoculations, one every 3-4 weeks containing 250mcg GM-CSF plus 500mcg peptide in the first five patients per arm (n=14) and 250mcg GM-CSF + 1000mcg of peptide in the second five patients (n=16).  Delayed-type hypersensitivity (DTH) and E39-specific CTLs were assessed at one and six months post-PVS. Thirty-nine patients were randomized into three arms with 30 breast (n=27) or ovarian (n=3) cancer patients completing the PVS and assessed for this presentation:

• E39 (GALE-301) x 6 inoculations (n=10)
• E39 (GALE-301) x 3 inoculations followed by E39’ (GALE-302) x 3 inoculations (n=10)
• E39’ (GALE-302) x 3 inoculations followed by E39 (GALE-301) x 3 inoculations (n=10)

About GALE-301 and GALE-302

GALE-301 and GALE-302 are cancer immunotherapies that consist of a peptide derived from Folate Binding Protein (FBP) combined with the immune adjuvant, granulocyte macrophage-colony stimulating factor (GM-CSF) for the prevention of cancer recurrence in the adjuvant setting.  GALE-301 is the E39 peptide, while GALE-302 is an attenuated version of this peptide, known as E39’.  FBP is a well-validated therapeutic target that is highly over-expressed in ovarian, endometrial and breast cancers, and is the source of immunogenic peptides that can stimulate cytotoxic T lymphocytes (CTLs) to recognize and destroy FBP-expressing cancer cells. Two trials are ongoing with FBP peptides: the GALE-301 Phase 2a portion of the Phase 1/2a clinical trial is ongoing in ovarian and endometrial adenocarcinomas (ClinicalTrials.gov Identifier: NCT01580696); the GALE-301 plus GALE-302 Phase 1b clinical trial is ongoing in breast and ovarian cancers (ClinicalTrials.gov Identifier: NCT02019524).

About Breast Cancer¹

New cases of breast cancer occur at an annual rate of 125 per 100,000 women in the U.S., with an estimated 246,660 new cases and 40,450 deaths in 2016. Approximately 89.7% of breast cancer patients are expected to survive five years after diagnosis. Approximately 12.4% of women will be diagnosed with breast cancer at some point during their lifetime (2011 – 2013 data).  The prevalence data from 2013 showed an estimated 3,053,450 women living with breast cancer in the United States.

About Ovarian Cancer¹

New cases of ovarian cancer occur at an annual rate of 11.9 per 100,000 women in the U.S., with an estimated 22,280 new cases and 14,240 deaths in 2016. Approximately 46.2% of ovarian cancer patients are expected to survive five years after diagnosis. Approximately 1.3% of women will be diagnosed with ovarian cancer at some point during their lifetime (2011 – 2013 data).  The prevalence data from 2013 showed an estimated 195,767 women living with ovarian cancer in the United States.

Due to the lack of specific symptoms, the majority of ovarian cancer patients are diagnosed at later stages of the disease, with an estimated 75% of women presenting with advanced-stage (III or IV) 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 many patients respond to this treatment regimen and become clinically free-of-disease, the majority of these patients will relapse.  Depending upon their level of residual disease, the risk for recurrence after completion of primary therapy ranges from 60% to 85%.  Unfortunately for these women, once the disease recurs, treatment options are limited and the disease remains incurable.

¹National Cancer Institute Surveillance, Epidemiology, and End Results Program

About Galena Biopharma

Galena Biopharma, Inc. is a biopharmaceutical company committed to the development and commercialization of hematology and oncology therapeutics that address unmet medical needs. Galena’s pipeline consists of multiple mid-to-late-stage clinical assets led by its hematology asset, GALE-401, and novel cancer immunotherapy programs including NeuVax™ (nelipepimut-S) and GALE-301/GALE-302. For more information, 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 development of Galena’s product candidates, including GALE-301 and GALE-302, patient enrollment in our clinical trials, as well as other statements related to the progress and timing of our development activities, present or future licensing, collaborative or financing arrangements, expected outcomes with regulatory agencies, and projected market opportunities for product candidates or that otherwise relate to future periods. 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, 2015 and most recent Quarterly Reports on Form 10-Q 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.

NeuVax is a trademark of Galena Biopharma, Inc.

Contact:

Remy Bernarda
SVP, Investor Relations & Corporate Communications
(925) 498-7709
[email protected]