Maintenance Dose Study of GEN-003 in Subjects With Genital Herpes Infection

This study is a randomized, double-blind, placebo-controlled clinical trial of GEN-003 in
subjects who have received previous doses of GEN-003 in the GEN-003-003 clinical trial.
Eligible subjects will be randomized in a 1:1 ratio to receive 1 intramuscular (IM) dose (the
maintenance dose) of GEN-003 or placebo.

Subjects will use a daily electronic reporting tool for reporting the presence or absence of
genital herpes lesions, and severity of genital herpes symptoms.

GEN-003-005 was originally designed to follow subjects for 12 months after the maintenance
dose but a business decision, unrelated to product safety, was made by Genocea Biosciences in
3Q2017 to cease GEN-003 spending and activities.

Inclusion Criteria:

- Completed Study GEN-003-003

- Received all 3 GEN-003 doses (any dose combination) in Study GEN-003-003

- Received last dose of GEN-003 within 11 to 18 months prior

- Reported data in the daily electronic reporting period on at least 80% of days in
Study GEN‑003-003

- Collected at least 45 swabs (of 56 total expected swabs) during the Month 11 to 12
swab collection period in Study GEN-003-003

- Willing and able to provide written informed consent

- Willing to perform and comply with all study procedures

- Postmenopausal or willing to practice a highly effective method of contraception for
28 days before and 90 days after enrollment

Exclusion Criteria:

- Did not meet all eligibility criteria in Study GEN-003-003, or received incorrect
treatment in Study GEN-003-003

- Use of suppressive antiviral medication within 14 days prior

- Use of topical steroids or antiviral medication in the anogenital region within 14
days prior

- Use of tenofovir, lysine, or other medication or supplement known or purported to
affect HSV recurrence frequency or intensity within 14 days prior

- History of any form of ocular HSV infection, HSV-related erythema multiforme, or
herpes meningitis or encephalitis

- Immunocompromised individuals

- Diagnosis or suspicion of an AESI

- Diagnosis or suspicion of any other autoimmune disease not listed in Appendix 4 of the
protocol

- Vaccine-related SAE in GEN-003-003

- Known current infection with HIV or hepatitis B or C virus

- History of hypersensitivity to any component of the vaccine

- Prior receipt of another vaccine containing HSV-2 antigens other than GEN-003

- Receipt of any IP within 30 days prior to the maintenance dose of GEN-003/placebo

- Receipt of any blood product within 90 days prior to the maintenance dose

- Receipt of a live vaccine within 28 days prior to or any other vaccine within 14 days
prior to maintenance dose

- Planned use of any vaccine from the maintenance dose to 28 days after the maintenance
dose

- Pregnant or nursing women

- History of drug or alcohol abuse

- Other active, uncontrolled comorbidities

- Changes to medication used to manage an underlying comorbidity within 60 days prior