ONCOLOGY FOCUSED IMMUNOTHERAPY COMPANY

Targeting cancer survivorship

FORWARD LOOKING STATEMENT

This presentation 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 target revenue from the sales of the Company’s products, the future expectations, plans and prospects for the development and commercialization of the Company's product candidates, including patient enrollment in our clinical trials, and are subject to a number of risks, uncertainties and assumptions, including those identified under “Risk Factors” in the Company’s most recently filed Annual Report on Form 10-K and Quarterly Report on Form 10-Q and in other filings the Company periodically makes with the SEC. Actual results may differ materially from those contemplated by these forward-looking statements. The Company 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 presentation.

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ONCOLOGY FOCUSED BIOPHARMACEUTICAL COMPANY

u Pioneering secondary prevention in cancer survivors •  Redefining the standard of care •  Targeted therapies for prevention of cancer recurrence

u 1st in class vaccines targeting targeting HER2 and Folate Binding Protein in breast and gynecological cancers

u Focused in large markets in areas of major unmet medical need •  Phase 3, PRESENT, breast cancer clinical trial ongoing under SPA

u Franchise of mid-stage trials ongoing or planned

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FIRST-IN-CLASS, TARGETED IMMUNOTHERAPY PIPELINE

4

Harnessing the power of the

immune system in the adjuvant setting

u  Exploits specificity of natural immune surveillance

u  Adjuvant patients have healthy immune systems

u  Systemic protection

Goal is to prevent recurrence

u  Recurrences are almost always fatal

u  Minimal toxicity and improved safety profile

u  Boosters provide long term protective effect

Well-validated targets

u  HER2

u  Folate binding protein (FBP)

Current Programs

u  NeuVax™ (nelipepimut-S)

•  Breast: HER2 1+, 2+ and 3+, DCIS

•  Gastric trial planned

u  GALE-301 & GALE-302

•  Ovarian

Adjuvant Setting = Minimal Residual Disease

DEVELOPMENT PIPELINE

Product Therapeutic Area Phase 1 Phase 2 Phase 3 BLA / NDA

Immunotherapy: Breast Cancer

NeuVax™ Node-positive HER2 IHC 1+/2+

NeuVax™ + Herceptin® Node-positive or node negative/triple negative HER2 IHC 1+/2+

NeuVax™ + Herceptin® High risk, node-positive or negative, HER2 IHC 3+

NeuVax™ Ductal Carcinoma in Situ (DCIS)

Immunotherapy: Gastric Cancer

NeuVax™ Gastric, HER2 IHC 1+/2+/3+

Immunotherapy: Gynecological Cancer

GALE-301 Ovarian & Endometrial

GALE-301 + GALE-302 Ovarian & Breast

Hematology

GALE-401 (Anagrelide CR) MPN-related thrombocytosis

PRESENT

*NeuVax is an investigational product. Efficacy has not been established. Herceptin is a registered trademark of Genentech.

Ongoing Planned

VADIS

5

Adds ~10k patients >$3B

Combo: High risk, HER2 3+

NEUVAX: SIGNIFICANT U.S. COMMERCIAL OPPORTUNITY

6

adds ~10k patients >$2.5B

Combo Node Pos or Neg HER2 1+, 2+

HLA-A2, A3, A24, A26

PRESENT 50-60k patients

>$2B

Source: Global Data 2015/Medtrack. Pricing estimates based on a 20% premium to the current average annual price of Herceptin® (U.S. Dollars).

Targeting HER2

7

NEUVAX™ (nelipepimut-S)

What it is

8

NEUVAX: HER2 IMMUNODOMINANT PEPTIDE

u  NeuVax contains the immunodominant peptide derived from the extracellular region of the HER2 protein

u  Peptide (aa 369-377) immunotherapy administered as intradermal injection

u  MHC Class I: HLA A2/A3

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K I F G S L A F L

ELICITS A STRONG CD8+ T-CELL RESPONSE

u NeuVax binds to antigen presenting cells (APCs)

u NeuVax stimulates APCs to activate CD8+ cytotoxic T lymphocytes (CTLs)

u CTLs rapidly replicate to seek out and destroy HER2 expressing tumor cells and micro-metastases

u Booster series maintains long term immunologic response

10

Sources: Peoples GE, et al (2005) JCO, 23(300, 7536-7545; Mittendorf EA, et al (2006) Surgery, 139(3): 407-418. Peoples, et al, ASCO 2012 Poster Presentation

0.4

1.8

0.7 0.5

0.0

0.5

1.0

1.5

2.0

2.5

% N

euVa

x sp

ecifi

c C

D8+

T c

ells

NeuVax Specific CD-8 CTLs: Pre-, Post, Mean and Long-Term (6 months)

Pre Max Mean Long-Term

T-Cell

Activating Receptors Inhibitory Receptors

CD28

OX40

GITR

CD122

CD27

CD360

HVEM

CD137

CTLA-4

PD-1

TIM-3

BTLA

VISTA

LAG-3

IMMUNO-ONCOLOGY – UNLOCKING THE POWER OF THE T-CELL

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Checkpoint inhibitors

Indirect Immune Modulators

Co-stimulators

Immune Inhibitory Enzymes

CAR T Technology

TCR Technology

T-Cell

Activating Receptors Inhibitory Receptors

CD28

OX40

GITR

CD122

CD27

CD360

HVEM

CD137

CTLA-4

PD-1

TIM-3

BTLA

VISTA

LAG-3

LACK OF REACTIVE T-CELLS MAY RENDER SOME TOOLS INEFFECTIVE IN MANY CANCERS

12

Checkpoint inhibitors

Indirect Immune Modulators

Co-stimulators

Immune Inhibitory Enzymes

T-Cell

CD28 OX40

GITR

CD122

CD27

CD360

HVEM

CD137

CTLA-4

PD-1

TIM-3

BTLA

VISTA

LAG-3

Activating Receptors Inhibitory Receptors

NEUVAX STIMULATES T-CELL PROLIFERATION AND EXPANSION

13

T cells

Checkpoint inhibitors

Indirect Immune Modulators

Co-stimulators

Immune Inhibitory Enzymes

T cells

T cells

T cells

T cells

T cells

T cells

T cells

T cells

T cells

Where it fits

14

UNIQUELY POSITIONED

u  14.5 million cancer survivors in US (NCI Cancer Survivorship)

•  Projected to 19 million survivors in 2024

u  Increase in survival due to decades of productive research, improved screening/prevention, and effective treatments

u  Survival leads to patients living longer

•  64% alive after 5 years of diagnosis •  41% alive after 10 years of diagnosis •  15% alive after 20 years or longer

u  Galena peptide vaccines – NeuVax and GALE-301 are uniquely positioned to maintain survivorship

15 Source: DeSantis CE et al. CA Cancer J Clin 2014: 64:252-271

REDEFINING THE STANDARD OF CARE

16

RECEIVES PRIMARY TREATMENT

• Surgery

• Chemotherapy

• Radiation

Slight evidence of disease

Disease free “survivor”

HER2 Status Standard of Care

HER2, 3+ (20-25% of patients)

Multiple, including Herceptin®

HER2, 1+/2+ (50-60% of patients)

No FDA approved therapies

HER2, 3+ High Risk (20-25% of patients)

•  PRESENT trial

•  NeuVax + trastuzumab

No FDA approved therapies •  NeuVax +

trastuzumab

BREAST CANCER PROGRAMS

Phase Treatment HER2Status Indica6on TrialStatus

ProtocolDefined

#ofPa6entsCollabora6ons

3SingleagentPRESENTStudy

1+,2+ NodePosi6veHLAA2+,A3+

Enrolled13countries~140centers

700(enrolled758)

2bCombina6on

withtrastuzumab

1+,2+

NodePosi6veorHighRiskNodeNega6ve

HLAA2+,A3+,A24+,A26+

EnrollingU.S.only34centers

300

2Combina6on

withtrastuzumab

3+highrisk

NodePosi6veHLAA2,A3+

EnrollingU.S.only30centers

100

2 SingleagentVADISStudy

1+,2+,3+

DuctalCarcinomainSitu(DCIS)HLAA2+

Planned4U.S.sites 48

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PRIMARY PREVENTION Expansion potential for safe vaccine in DCIS

METASTATIC DISEASE Expansion potential in combination with checkpoint inhibitors /immune modulators

NEUVAX: ACROSS THE BREAST CANCER TREATMENT SPECTRUM

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PROOF OF CONCEPT: Established in population with no standard of care treatment options

SECONDARY PREVENTION

IDEAL SETTING: Adjuvant treatment in patient population with no evidence of disease

MOST ADVANCED: PRESENT is the largest and only Phase 3 breast cancer vaccine trial

Where it stands

19

SN-33 PHASE 2 HER2 IHC 1+/2+ (N=45)

20

Source: 2012 San Antonio Breast Cancer Poster, Mazanet, et al.

PHASE 3, PRESENT TRIAL

Prevention of Recurrence in Early-Stage, Node Positive Breast Cancer with Low to Intermediate Her2 Expression with NeuVax Treatment u Trial being run under FDA-approved SPA

u Enrollment completed in April 2015 (n=758) •  Adjuvant breast cancer patients, Node Positive, HER2 1+/2+, HLA A2/A3+

u Patient friendly regimen via intradermal injection •  Primary Vaccine Series – injection once a month for 6 months •  Booster Series – injection once every 6 months

u Upcoming Key Milestones •  Interim safety/futility analysis: 2Q16 •  Final Endpoint: 2018

21

PHASE 3 PRESENT TRIAL PER SPA

1 2 3 4

Interim analysis by DSMB at n=70 events

Endpoint DFS at n=141 events /

36 months

Dosing by Month + 1 booster dose every 6 months thereafter

5 6

Adjuvant breast cancer patients, randomized 1:1

§  Double blind

§  Node positive

§  HLA A2/A3+

§  HER2 IHC 1+/2+

§  Stratified by stage, type of surgery, hormone receptor, and menopausal status

§  Enrollment complete: n=758 Patients

Study Population + GM-CSF

Placebo + GM-CSF

22

Prevention of Recurrence in Early-Stage, Node Positive Breast Cancer with Low to Intermediate Her2 Expression with NeuVax Treatment

NEUVAX FRANCHISE EXPANSION OPPORTUNITIES

23

Breast Cancer HER2 1+/2+

Development Priority

1°

Breast Cancer HER2 1+/2+/3+ w/Herceptin

Gastric Cancer HER2 1+/2+/3+

Ductal Carcinoma in Situ (DCIS)

Breast Cancer Node Negative, HER2 1+/2+

Bladder Cancer

Prostate Cancer

Non Small Cell Lung Cancer

Breast Cancer HER2 1+/2+/3+ w/Checkpoint Inhibitor

Colorectal Cancer

Ovarian Cancer

2° 3°

Note: Boxed programs are underway or planned.

GALE-301 & GALE-302

Targeting Folate Binding Protein

24

GALE-301: FOLATE BINDING PROTEIN (FBP)

25

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

Vaccine Control

% o

f Sub

ject

s

Recurrence

24.0% 13.3%

Source: U.S. Ovarian Cancer http://seer.cancer.gov/statfacts/html/ovary.html

u Targeted cancer immunotherapy

u FBP is over-expressed (20-80 fold) in >90% of ovarian and endometrial cancers

u FBP has very limited tissue distribution and expression in non-malignant tissue making it an ideal immunotherapy target

u Current treatments are generic •  Carboplatin and paclitaxel •  High recurrence rate

u Most patients relapse with poor prognosis

GALE-301 & GALE-302: CURRENT CLINICAL DEVELOPMENT

26

Phase Treatment CancerType TargetIndica6on

CurrentStatus

#ofEnrolledPa6ents

1/2a GALE-301Ovarian,

Endometrial HLAA2+

Ovarian Enrolled 51

1b GALE-301&GALE-302

Ovarian,BreastHLAA2+ Ovarian Enrolled 39

GALE-301: PHASE 1/2a TRIAL

1 2 3 4

Dosing by Month + 1 booster dose every 6 months thereafter 5 6

Diseasefree(NED)ovarianandendometriala[erSoCRx

§  Nodeposi6ve

§  HLAA2+-Vaccine

§  HLAA2-Control

§  N=51

StudyPopula6on

GALE-301+GM-CSF

100 µg GALE-301+GM-CSF

500 µg

GALE-301+GM-CSF

1000 µg

Phase 1 Dose Escalation

GALE-301+GM-CSF

Phase 2 Optimal Dose

Source: ClinicalTrials.gov Identifier: NCT01580696) 27

GALE-301: OPTIMAL DOSE GROUP SHOWS PRELIMINARY EFFICACY

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

Vaccine Control

% o

f Sub

ject

s

Recurrence

24.0% 13.3%

Source: Peoples, et. al, Poster Presentation, European Cancer Congress 2015 28

Phase 1/2a trial ongoing u  Phase 1: Determined optimal dose and

demonstrated safety and potent immune response

u  Phase 2a Preliminary data in 1000 mcg dose group:

•  At 12 months median follow-up:

§  Vaccine group: two clinical recurrences (13.3%) n=15

§  Control group: 12 recurrences (55%) n=22

•  2 year DFS estimate in 1000 mcg dose group is 85.7% vaccine vs. 33.6% control (p<.02)

•  GALE-301 plus GM-CSF is well tolerated and elicits a strong in vivo immune response with primarily Grade 1 and Grade 2 toxicities

2 Year DFS Estimate by Dose Cohort

GALE-301 (E39) & GALE-302 (E39’): PHASE 1b TRIAL

Diseasefree(NED)ovarianandbreastcancera[erSoCRx

§  Nodeposi6ve

§  HLAA2+(Vaccine)

§  HLAA2-(Control)

§  Post menopausal

§  N=39

StudyPopula6onGALE-301+GM-CSFx6

Phase 1 Primary Vaccination Series (PVS)

Endpoints: •  Immunologic

response assessed by local reaction (LR) after each vaccination

•  Delayed-type hypersensitivity (DTH) reaction after completion

Source: ClinicalTrials.gov Identifier: NCT020196524

GALE-302+GM-CSFx3àGALE-301+GM-CSFx3

GALE-301+GM-CSFx3àGALE-302+GM-CSFx3

29

1 2 3 4

Dosing by Month + 1 booster dose every 6 months x2 5 6

GALE-301 & GALE 302: DELAYED-TYPE HYPERSENSITIVITY

30

LEGEND EE = E39 (GALE-301) x 6 inoculations (n=12) EE’ = E39 (GALE-301) x 3 inoculations followed by E39’ (GALE-302) x 3 inoculations (n=14) E’E = E39’ (GALE-302) x 3 inoculations followed by E39 (GALE-301) x 3 inoculations (n=13)

R0 = baseline (pre-vaccination) RC1 = 1 month after completion of the PVS RC6 = 6 months after completion of the PVS and pre-booster

Source: Mittendorf et. al., Poster Presentation, Society of the Immunotherapy of Cancer 2015

GALE-401

Anagrelide Controlled Release (CR)

31

GALE-401 ANAGRELIDE CONTROLLED RELEASE (CR)

32

Indication & Current Treatment

u  Active ingredient = anagrelide u  Anagrelide reduces the elevated platelet count

and the risk of thrombosis u  Immediate release (IR) version approved for the

treatment of patients with thrombocythemia, secondary to myeloproliferative neoplasms (MPNs) •  MPNs are hematological malignancies in which the

bone marrow cells develop and function abnormally

u  IR formulation can cause unacceptable side effects •  Believed to be Cmax-related and has largely limited the

use due to early treatment withdrawal

u  Controlled Release (CR) formulation may decrease the frequency or severity of side effects

u  Phase 2, Proof-of-Concept, Trial Ongoing

u  If successful, Galena will seek approval via the 505(b)(2) regulatory pathway

GALE-401

Source: Anagrelide Package Insert

GALE-401: PHASE 2 PILOT STUDY FINAL RESULTS

33

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

Vaccine Control

% o

f Sub

ject

s

Recurrence

24.0% 13.3%

Source: ASH 2015 Poster Presentation, Verstovsek et al.

u Well tolerated with primarily Grade 1 and 2 toxicities in n=14/18

u Efficacy compares favorably to historical anagrelide IR

•  Platelet response: §  ORR = 83.3% (15/18) §  CR = 61.1% (11/18) §  PR = 22.2% (4/18)

•  Median time to response was 1 to 9 weeks (defined as platelet count ≤ 600 x109/L)

§  Anagrelide IR historical time to response ranged from 4 to 12 weeks

Figure2.PlateletResponse

1 8 15 22 29 36 43 50 57 64 71 78 85 99 113 127 141 155 169 197 225

18 18 18 18 18 18 15 14 14 14 13 13 13 13 13 13 12 12 11 11 11

1.0 1.4 1.8 1.9 2.0 2.2 2.4 2.5 2.4 2.2 2.0 2.1 2.1 1.9 1.8 1.9 2.0 1.9 1.8 1.9 1.8

StudyDays

N=

Avg.dailydose

0

200

400

600

800

1000

1200

1400 Mean Platelet Count (± SD)

Plat

elet

Cou

nt (x

109 /L

)

Figure2.PlateletResponse

1 8 15 22 29 36 43 50 57 64 71 78 85 99 113 127 141 155 169 197 225

18 18 18 18 18 18 15 14 14 14 13 13 13 13 13 13 12 12 11 11 11

1.0 1.4 1.8 1.9 2.0 2.2 2.4 2.5 2.4 2.2 2.0 2.1 2.1 1.9 1.8 1.9 2.0 1.9 1.8 1.9 1.8

StudyDays

N=

Avg.dailydose

0

200

400

600

800

1000

1200

1400 Mean Platelet Count (± SD)

Plat

elet

Cou

nt (x

109 /L

)

Figure2.PlateletResponse

1 8 15 22 29 36 43 50 57 64 71 78 85 99 113 127 141 155 169 197 225

18 18 18 18 18 18 15 14 14 14 13 13 13 13 13 13 12 12 11 11 11

1.0 1.4 1.8 1.9 2.0 2.2 2.4 2.5 2.4 2.2 2.0 2.1 2.1 1.9 1.8 1.9 2.0 1.9 1.8 1.9 1.8

StudyDays

N=

Avg.dailydose

0

200

400

600

800

1000

1200

1400 Mean Platelet Count (± SD)

Plat

elet

Cou

nt (x

109 /L

)

Figure2.PlateletResponse

1 8 15 22 29 36 43 50 57 64 71 78 85 99 113 127 141 155 169 197 225

18 18 18 18 18 18 15 14 14 14 13 13 13 13 13 13 12 12 11 11 11

1.0 1.4 1.8 1.9 2.0 2.2 2.4 2.5 2.4 2.2 2.0 2.1 2.1 1.9 1.8 1.9 2.0 1.9 1.8 1.9 1.8

StudyDays

N=

Avg.dailydose

0

200

400

600

800

1000

1200

1400 Mean Platelet Count (± SD)

Plat

elet

Cou

nt (x

109 /L

)

CORPORATE OVERVIEW

34

COMMERCIAL ASSETS

u Divestiture plan announced: Nov. 9, 2015

u Abstral® (fentanyl) sublingual tablets •  Approved for breakthrough

cancer pain •  SOLD: Nov 20, 2015

u Zuplenz® (ondansetron) oral soluble film •  Approved for CINV, RINV, PONV •  For Sale

35 Please see full prescribing information at www.abstral.com and www.zuplenz.com.

UPCOMING MILESTONES

NeuVax™

ü  Enroll N=700 into PRESENT trial ü  Complete enrollment in Phase 3 PRESENT trial •  Initiate DCIS trial (1Q16) •  PRESENT: reach 70 events (1Q16) •  PRESENT: interim analysis (2Q16)

GALE-301 GALE-302

ü  Report Top-Line Phase 2a clinical data ü  Report 1-Year Phase 2a analysis ü  Report GALE-301 + GALE-302 Phase 1b data

GALE-401 (anagrelide CR)

ü  Report Top-Line efficacy and safety data ü  Report Final Phase 2 data

36

LEADERSHIP TEAM

37

u  Mark W. Schwartz, Ph.D., President & CEO Apthera, Bayhill Therapeutics, Calyx Therapeutics, Trega Biosciences, Incyte Genomics, DuPont Diagnostics

u  Bijan Nejadnik, M.D., Executive Vice President, Chief Medical Officer Jazz Pharmaceuticals, Johnson & Johnson, Stanford, Johns Hopkins, UC Davis

u  Ryan Dunlap, CPA, VP & CFO Moss Adams, Nike, KPMG, PricewaterhouseCoopers

u  Remy Bernarda, SVP, Investor Relations & Corporate Communications IR Sense, Hana Biosciences, Knight Equity Markets, Bear Stearns, Goldman Sachs

u  Gavin Choy, Pharm.D., SVP, Clinical Sciences & Operations Otsuka, Astex, SuperGen, Hana Biosciences, Gilead, Stanford University Medical Center, Department of Veteran Affairs

u  Tom Knapp, Esq., Interim General Counsel Sucampo, Exemplar Law Partners, NorthWestern Energy, Paul Hastings, The Boeing Company

u  Joe Lasaga, VP, Business Development & Alliance Management

Nektar Therapeutics, Rigel

u  Pat Murphy, VP, Regulatory Affairs & Compliance Nektar Therapeutics, Bayhill Therapeutics, Berlex Laboratories, Serono, Parexel, Biogen

FINANCIAL OVERVIEW (as of September 30, 2015)

Cash & Cash Equivalents $34.8 million

Debt $5.7 million

Projected Quarterly Burn $9-$11 million

Shares Outstanding 162 million

Market Cap (7 December 15) ~$240 million

38

WHY WE’RE HERE

39 Source: E75 vaccine's final tests start in S.A. By Don Finley, January 22, 2012; Photo credit: Kin Man Hui/San Antonio Express-News/ZUMAPress

“I've had several friends who've had (breast cancer) and then…it came back and they had to go through treatment again. So this would be wonderful, not to have to come back.”

– First NeuVax Phase 3 patient

THANK YOU

NASDAQ: GALE