8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 20, 2015

GENOCEA BIOSCIENCES, INC.

(Exact name of registrant as specified in its charter)

Delaware	001-36289	51-0596811
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

Cambridge Discovery Park 100 Acorn Park Drive, 5th Floor
Cambridge, MA	02140
(Address of principal executive offices)	(Zip Code)

(Registrant’s telephone number, including area code): (617) 876-8191

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01. Regulation FD Disclosure.

On May 20, 2015, Genocea Biosciences, Inc. (the “Company”) issued a press release announcing top-line data from the Company’s Phase 2 dose optimization trial evaluating the immunotherapy GEN-003 for the treatment of genital herpes. A copy of the press release, dated May 20, 2015, is attached to this Current Report on Form 8-K as Exhibit 99.1 and is incorporated herein by reference.

The information contained in this Item 7.01 of this Current Report on Form 8-K, including the exhibit attached hereto, is being furnished and shall not be deemed “filed” for any purpose, and shall not be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, regardless of any general incorporation language in any such filing.

Item 8.01 Other Events.

On May 20, 2015, the Company gave a presentation to certain investors regarding the top-line data from the Company’s Phase 2 dose optimization trial evaluating the immunotherapy GEN-003 for the treatment of genital herpes.  A copy of the presentation is attached to this Current Report on Form 8-K as Exhibit 99.2 and is incorporated herein by reference.  The presentation is also available on the Company’s website, www.genocea.com, however the Company’s website and any information contained on the website are not incorporated herein.

Item 9.01 Financial Statements and Exhibits.

See Exhibit Index attached hereto.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	GENOCEA BIOSCIENCES, INC.
By:	/s/ Jonathan Poole
	Jonathan Poole Chief Financial Officer

Date: May 20, 2015

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EXHIBIT INDEX

Exhibit No.	Description
99.1	Press Release issued by Genocea Biosciences, Inc. on May 20, 2015
99.2	Investor Presentation dated May 20, 2015

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EX-99.1

Exhibit 99.1

For media:	For investors:
Megan Lustig	Jonathan Poole
Spectrum Science Communications	Genocea Biosciences
O: 202-955-6222	O: 617-876-8191
mlustig@spectrumscience.com	jonathan.poole@genocea.com

Genocea Announces Positive Top-Line Phase 2 Data

for Genital Herpes Immunotherapy GEN-003

- Highly statistically significant 55 percent reduction in viral shedding rate with best dose -

- Company to host conference call at 9 a.m. EDT today including guest speaker Peter A. Leone, MD -

CAMBRIDGE, MA, May 20, 2015 —(BUSINESS WIRE)— Genocea Biosciences, Inc. (NASDAQ:GNCA), a biopharmaceutical company developing T cell-directed vaccines and immunotherapies, today announced positive top-line data from a Phase 2 dose optimization trial evaluating GEN-003 for the treatment of genital herpes. During the 28-day observation period immediately after completion of dosing, the best dose of 60 µg per protein / 75 µg of Matrix-M2TM adjuvant demonstrated a highly statistically significant (p<0.0001) 55 percent reduction from baseline in the viral shedding rate, the primary endpoint of the trial and a measure of anti-viral activity. All dose combinations tested, including the successful 30 µg per protein / 50 µg of adjuvant dose from the prior Phase 1/2a trial, demonstrated a statistically significant viral shedding rate reduction versus baseline and only the lowest dose combination did not demonstrate a statistically significant reduction versus placebo.

In a planned secondary analysis to assess impact on patient-reported genital lesion rates, a self-assessed measurement of clinical disease, all dose groups, including the placebo group, demonstrated a statistically significant reduction from baseline.

“We are extremely pleased with these positive top-line results which have successfully allowed us to identify the optimal dose to advance into further trials,” said Chip Clark, president and chief executive officer. “The results strengthen the product profile from our Phase 1/2a trial, which we have shown in market research to be highly clinically meaningful and commercially attractive, providing further evidence of the strong value proposition of GEN-003 for patients, physicians and payers.”

The Phase 2 study showed that GEN-003 was generally safe and well tolerated by patients, with no serious adverse events related to the vaccine. Safety data throughout the trial is monitored by an independent data safety monitoring board. Although reactogenicity increased with adjuvant dose, there was no difference in discontinuations in patient dosing due to adverse events across the different treatment arms.

“People living with genital herpes are seeking treatments that deliver on efficacy and provide them with peace of mind that they are at less risk of transmitting the infection to their sexual partners,” said Peter Leone, MD, Professor of Medicine and Adjunct Professor of Epidemiology at the University of North Carolina, and an investigator in the GEN-003 dose optimization trial. “We know that asymptomatic viral shedding is the driver of herpes transmission and GEN-003’s demonstrated antiviral efficacy data reported to date suggest this immunotherapy can be an effective future treatment.”

About the GEN-003 Phase 2 Clinical Trial

The Phase 2 study enrolled 310 subjects from 17 institutions in the United States. Subjects were randomized to one of six dosing groups of either 30 µg or 60 µg per protein paired with one of three adjuvant doses (25 µg, 50 µg, or 75 µg). A seventh group received placebo. Subjects received three doses of GEN-003 or placebo at 21-day intervals. Baseline viral shedding and genital lesion rates were established for each subject in a 28-day observation period prior to the commencement of dosing by collecting 56 genital swab samples (two per day), which were analyzed for the presence of HSV-2 DNA, and by recording the days on which genital lesions were present. This 28-day observation period was repeated immediately after the completion of dosing and will be repeated two more times over the course of this trial, at six and twelve months following dosing. No booster doses will be given.

A prior Phase 1/2a clinical trial demonstrated, at the corresponding immediate post dosing 28-day observation period, a highly statistically significant 52 percent reduction in the viral shedding rate and a highly statistically significant 48 percent reduction in the genital lesion rate compared to baseline at a dose of 30 µg per protein/50 µg of Matrix-M2TM adjuvant.

For more information about this clinical study of GEN-003 please visit www.clinicaltrials.gov.

Conference Call

Genocea management will host a conference call and webcast today, at 9 a.m. EDT. Peter A. Leone, MD, Professor of Medicine and Adjunct Professor of Epidemiology at the University of North Carolina, will also join management for the call. Dr. Leone is an expert in the surveillance, prevention, and control of sexually transmitted diseases and is an investigator in the GEN-003 dose optimization trial. The conference call may be accessed by dialing (844) 826-0619 for domestic participants and (315) 625-6883 for international callers (reference conference ID 52068310). A live webcast of the conference call will be available online from the investor relations section of the Company’s website at http://ir.genocea.com. A webcast replay of the conference call will be available on the Genocea website beginning approximately two hours after the event, and will be archived for 30 days.

About GEN-003

Inducing a T cell response against HSV-2 is critical to treating the clinical symptoms of disease and controlling transmission of the infection. GEN-003 is a first-in-class T-cell directed immunotherapy designed to elicit both a T cell and B cell (antibody) immune response. The immunotherapy was designed using Genocea’s ATLAS™ platform, which profiles the comprehensive spectrum of actual T cell responses mounted by humans in response to disease, to identify antigen targets that drive T cell response. GEN-003 includes the antigens ICP4 and gD2 along with Matrix-M2TM adjuvant, which Genocea licensed from Novavax, Inc.

For more information about GEN-003, please visit http://www.genocea.com/platform-pipeline/pipeline/gen003-for-genital-herpes/

About Genital Herpes

Genital Herpes affects more than 400 million people worldwide and causes recurrent, painful genital lesions. It can be transmitted to sexual partners, even when the disease is asymptomatic. Current genital herpes therapies only partially control clinical symptoms and viral shedding, a process which drives disease transmission. Incomplete control of genital lesions and transmission risk, expense and the perceived inconvenience of taking a daily medication are hurdles for long-term disease management. Immunity through T cells is believed to be particularly critical to the control and possible prevention of genital herpes infections.

About Genocea

Genocea is harnessing the power of T cell immunity to develop life-changing vaccines and immunotherapies. T cells are increasingly recognized as a critical element of protective immune responses to a wide range of diseases, but traditional discovery methods have proven unable to identify the targets of such protective immune response. Using ATLAS™, its proprietary technology platform, Genocea identifies these targets to potentially enable the rapid development of medicines to address critical patient needs. Genocea’s pipeline of novel clinical stage T cell-enabled product candidates includes GEN-003 for genital herpes, GEN-004 for the prevention of infection by all serotypes of pneumococcus, and earlier-stage programs in chlamydia, genital herpes prophylaxis, malaria and cancer immunotherapy. For more information, please visit the company’s website at www.genocea.com.

Forward Looking Statements

Statements herein relating to future business performance, conditions or strategies and other financial and business matters, including expectations regarding clinical developments, are forward-looking statements within the meaning of the Private Securities Litigation Reform Act. Genocea cautions that these forward-looking statements are subject to numerous assumptions, risks and uncertainties, which change over time. Factors that may cause actual results to differ materially from the results discussed in the forward-looking statements or historical experience include risks and uncertainties, including Genocea’s ability to progress any product candidates in preclinical or clinical trials; the scope, rate and progress of its preclinical studies and clinical trials and other research and development activities; anticipated clinical trial results; that current results may not be predictive of future results; even if the data from preclinical studies or clinical trials is positive, regulatory authorities may require additional studies for approval and the product may not prove to be safe and efficacious; Genocea’s ability to enter into future collaborations with industry partners and the government and the terms, timing and success of any such collaboration; risks associated with the manufacture and supply of clinical and commercial product; the cost of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights; Genocea’s ability to obtain rights to technology; competition for clinical resources and patient enrollment from drug candidates in development by other companies with greater resources and visibility; the rate of cash utilized by Genocea in its business and the period for which existing cash will be able to fund such operation; Genocea’s  ability to obtain adequate financing in the future through product licensing, co-promotional arrangements, public or private equity or debt financing or otherwise; general business conditions; competition; business abilities and judgment of personnel; the availability of qualified personnel and other factors set forth under “Risk Factors” in Genocea’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014 and other filings with the Securities and Exchange Commission (the “SEC”). Further information on the factors and risks that could affect Genocea’s business, financial conditions and results of operations is contained in Genocea’s filings with the SEC, which are available at www.sec.gov. These forward-looking statements speak only as of the date of this press release and Genocea assumes no duty to update forward-looking statements.

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EX-99.2

Exhibit 99.2

GEN-003 Immunotherapy for Genital Herpes Phase 2 Dose Optimization Study Top Line Results Immediate post dosing observation period 20 May 2015

Safe Harbor Statement This presentation contains “forward-looking” statements that are within the meaning of federal securities laws and are based on our management’s beliefs and assumptions and on information currently available to management. Forward-looking statements include information concerning our possible or assumed future results of operations, business strategies, financing plans, competitive position, industry environment, potential growth opportunities, potential market opportunities and the effects of competition. Forward-looking statements include all statements that are not historical facts and can be identified by terms such as “anticipates,” “believes,” “could,” “seeks,” “estimates,” “intends,” “may,” “plans,” “potential,” “predicts,” “projects,” “should,” “will,” “would” or similar expressions and the negatives of those terms. Forward-looking statements represent our management’s beliefs and assumptions only as of the date of this presentation. Our operations involve risks and uncertainties, many of which are outside our control, and any one of which, or combination of which, could materially affect our results of operations and whether the forward-looking statements ultimately prove to be correct. Factors that may materially affect our results of operations include, among other things, those listed in our Annual Report on Form 10-K and other filings with the Securities and Exchange Commission (“SEC”). Except as required by law, we assume no obligation to update these forward-looking statements publicly, or to update the reasons actual results could differ materially from those anticipated in the forward-looking statements, even if new information becomes available in the future. You may get copies of our Annual Report on Form 10-K, Quarterly Report on Form 10-Q and our other SEC filings for free by visiting EDGAR on the SEC website at http://www.sec.gov. 2

Agenda for Today’s Call Market potential for GEN-003 Phase 2 dose optimization trial Study design Top line data Dose selection Physician perspective – Dr. Peter A. Leone Development path to Phase 3 Conclusions Q&A 3

The Need for GEN-003 Drives Large Market Opportunity Genital herpes characterized by viral shedding, leading to disease transmission and genital lesions Oral antiviral therapy insufficient for millions Viral shedding reduced only when patients are taking medication but most use episodically Outbreaks still occur even on chronic therapy GEN-003 designed using ATLAS to direct T and B cells to fight infection by reducing viral activity GEN-003 product profile drives revenue opportunity of >$1bn in US alone 4

Phase 2 Dose Optimization Trial Goals and Objectives Overall goal: Justify dose selection for late stage clinical trials Primary endpoint: Compare combinations of antigens and adjuvant by impact on viral shedding Secondary objectives: Evaluate impact on clinical disease Lesion rates Time to next recurrence(a) Proportion recurrence free at 6 and 12 months(a) Safety and tolerability Immunogenicity(a) 5 (a) Not part of top-line read-out

Study Design Randomized, double-blind, placebo-controlled 310 subjects with chronic genital HSV-2 infection Assigned to 1 of 6 active treatment groups or placebo 2 dose levels of proteins: 30 or 60 µg 3 dose levels of Matrix-M2 adjuvant: 25, 50 or 75 µg Highly consistent with Phase 1/2a Demographics, inclusion / exclusion, sites, dose regimen, endpoints, observation period, swabbing compliance, statistical methods 6

Viral Shedding Rate Reductions a Clear Confirmation of Clinically and Commercially Meaningful Virologic Efficacy 7 Broad impact on viral shedding across all dose groups confirms Ph 1/2a results 60 µg per protein more effective at reducing viral shedding than 30 µg Clear adjuvant dose response important for FDA 30 µg per protein Viral Shedding Rate Reduction by Dose Group 60 µg per protein Ph 1/2a *** ††† *** ††† *** ††† *** ††† *** †† * Poisson model analysis vs. baseline *** p<0.0001, * p<0.05 vs. placebo ††† p<0.0001, †† p<0.0005 - 4% - 17% - 38% - 36% - 44% - 41% - 55% -60% -50% -40% -30% -20% -10% 0% Placebo 25 µg 50 µg 75 µg 25 µg 50 µg 75 µg Reduction in Viral Shedding Rate vs. Baseline

Genital Lesion Rate Reduction Also Greater for 60 µg per Protein Dose Groups. Placebo Effect Also Evident 8 Significant reductions in lesions in all dose groups Observed placebo effect 30 µg per protein Genital Lesion Rate Reduction by Dose Group 60 µg per protein Ph 1/2a *** *** *** * *** *** *** Poisson model analysis vs. baseline *** p<0.0001, * p<0.05 - 62% - 47% - 31% - 49% - 65% - 69% - 60% -80% -70% -60% -50% -40% -30% -20% -10% 0% Placebo 25 µg 50 µg 75 µg 25 µg 50 µg 75 µg Reduction in Genital Lesion Rate vs. Baseline

Reduction in Viral Shedding Drives Confidence in Achieving Attractive Product Profile Confirmation of clinically and commercially meaningful virologic efficacy of GEN-003 Best dose combination was 60 µg per protein / 75 µg of adjuvant Met FDA requirement for adjuvant dose titration Placebo effect confounds interpretation of patient-reported lesion rates 9

Overall Summary of Safety Safety continuously reviewed by Independent DSMB No modifications to study were requested Moderate reactogenicity that generally decreased with subsequent dosing No grade 4 reactogenicity or related SAEs <3% discontinuation rate due to AE’s distributed equally across dose groups including placebo 10

GEN-003 Physician Perspective Dr. Peter A. Leone Professor of Medicine and Adjunct Professor of Epidemiology at the University of North Carolina 11

Broadened Development Plan Enabled by Current Results 12 2016 2015 Post Dose 3 Q4 6 month Q1 12 month Q4-2016 2017 Post Dose 3 6 month 12 month Dose Optimization Select best dose Bridging Confirm profile of scaled-up drug product 6 month 12 month Dose Regimen Compare effects of number of doses Studies in expanded populations >50’s, HSV-1, HIV etc. Phase 3 FDA End of Phase 2 Meeting

Conclusions 13 GEN-003 continues to lead with a strengthened product profile Optimal dose identified and justified Reinforces confidence in >$1bn revenue opportunity for GEN-003 in US alone Clear path to FDA End of Phase 2 meeting next year and initiation of Phase 3 in 2017

Questions & Answers 14

Jonathan Poole Chief Financial Officer Phone: +1 617-876-8191 jonathan.poole@genocea.com Megan Lustig Spectrum Science Communications Phone: +1 202-955-6222 mlustig@spectrumscience.com Investor inquiries: Media inquiries: