Where each herpes vaccine candidate actually stands
A neutral, evidence-first tracker of herpes-simplex-virus (HSV) vaccine research. Every status claim is sourced and dated. We do not sell anything, promise timelines, or promote any candidate.
- 16 candidates tracked
- 2 with a trial listed as ongoing
- 4 not yet tested in people
- No approved HSV vaccine as of 2026
Candidates tested in people
Trial listed as ongoing · 2
BCHT HSV-2 mRNA vaccine phase 1 Changchun BCHT HSV-2 · aim unclear · mRNA Trial ongoing Phase 1 dose-escalation safety trial of an mRNA vaccine, enrolling by invitation. No results posted.
Last primary-sourced change: Oct 2025, Phase 1 trial started (registry) BNT163 phase 1 BioNTech HSV-2 · prophylactic · mRNA Trial ongoing Phase 1 first-in-human safety trial, active but no longer recruiting. Only a conference abstract on early safety and immune response; no efficacy data.
Last primary-sourced change: Oct 2025, Conference abstract reported early safety and immune data
No trial listed as ongoing · 6
G103 phase 1 Sanofi Pasteur HSV-2 · therapeutic · protein subunit No ongoing trial Three-protein therapeutic vaccine. A 2025 report covers 24 participants; the related Sanofi trial was terminated for business reasons.
Last primary-sourced change: May 2021, Related Sanofi trial terminated (registry) GSK4108771A phase 1 GlaxoSmithKline HSV type unclear · aim unclear · other No ongoing trial Phase 1 dose-escalation trial terminated in 2021 to develop an enhanced version. No results posted.
Last primary-sourced change: May 2021, Phase 1 trial terminated (registry) HerpV phase 2 Agenus HSV-2 · therapeutic · protein subunit No ongoing trial Phase 2a trial in 80 adults completed in 2015, with results posted. No record lists an ongoing trial.
Last primary-sourced change: Jan 2015, Phase 2a trial completed (registry) HSV529 phase 1 Sanofi Pasteur HSV-2 · prophylactic and therapeutic · replication-defective live No ongoing trial Three phase 1 trials. Raised antibodies in people never infected, not in those already infected. No efficacy trial; none active.
Last primary-sourced change: May 2021, Related Sanofi trial terminated (registry) pPJV7630 phase 1 PowderMed HSV-2 · therapeutic · DNA No ongoing trial Two phase 1 trials, completed in 2005 and 2006. No results posted on the registry.
Last primary-sourced change: Dec 2006, Second phase 1 trial completed (registry) VCL-HB01 phase 2 Vical HSV-2 · therapeutic · DNA No ongoing trial Phase 1/2 and phase 2 trials (165 and 261 people) completed by 2018. No results posted on the registry.
Last primary-sourced change: Dec 2018, Phase 2 trial completed (registry)
Discontinued · 3
GEN-003 discontinued Genocea HSV-2 · therapeutic · protein subunit Therapeutic vaccine that reduced viral shedding and lesion rates in phase 2. Genocea halted the program in 2017 and no one has revived it.
Last primary-sourced change: Jun 2018, Last registered trial closed, terminated (registry) Herpevac (gD2 subunit, GSK) discontinued GlaxoSmithKline HSV-2 · prophylactic · protein subunit Phase 3 in about 8,300 women: did not prevent HSV-2 genital disease, but reduced HSV-1 genital disease by about 58%. Not advanced.
Last primary-sourced change: Jan 2012, Phase 3 results published mRNA-1608 discontinued Moderna HSV-2 · therapeutic · mRNA Phase 1/2 completed April 2025 with interim safety and immune-response data reported. Trade press reported in November 2025 that Moderna ended the program.
Last primary-sourced change: Nov 2025, Trade press reported Moderna ended the program
Not yet tested in people
Show the 4 programs
gG-2 vaccine (EXCT4) preclinical University of Gothenburg HSV-2 · aim unclear · protein subunit Mouse studies only, reporting protection against lethal HSV-2 challenge. No human data and no registered trial.
Last primary-sourced change: 2026, Latest mouse study published Prime/Pull/Keep therapeutic vaccines preclinical UC Irvine (BenMohamed lab) HSV-1 and HSV-2 · therapeutic · other Guinea-pig and rabbit studies only, in already-infected animals. The antigens vary between papers. No human data or registered trial.
Last primary-sourced change: Apr 2025, Latest rabbit study (HSV-1) published Trivalent gC2/gD2/gE2 mRNA (UPenn) preclinical University of Pennsylvania HSV-2 · prophylactic · mRNA Mouse, guinea pig and primate studies only. Its clinical form is BioNTech's BNT163.
Last primary-sourced change: Jun 2026, Latest mouse study published ΔgD-2 preclinical Albert Einstein College of Medicine HSV-1 and HSV-2 · prophylactic · replication-defective live Mouse studies only, reporting protection against HSV-1 and HSV-2 disease. No human data and no registered trial.
Last primary-sourced change: 2023, Latest mouse study published
Research and background
Latest research
- A Tissue-Targeted Immunotherapy Protects Against Recurrent Ocular Herpes Infection and Disease, and Alleviates the Associated Cognitive, Behavioral, and Social Deficits in a 'Humanized' HLA Transgenic Mouse Model of UVB-Induced Reactivation
- A Decade of the Global STI Vaccine Roadmap: Progress, Gaps and Challenges
- HSV-2 gC2 mRNA immunization in mice protects by producing antibodies that bind immune evasion epitopes
Common questions about herpes vaccines
Is there a herpes vaccine?
No herpes (HSV) vaccine is approved anywhere as of 2026. Several candidates have entered or completed early-stage human trials, but none has been shown to prevent or treat herpes in the way needed for approval. See the candidate tracker →
Is a herpes vaccine coming in 2026?
There is no approved herpes vaccine and no announced approval date. The programs with trials still under way are in early-phase (Phase 1) testing, and a trial existing is not evidence that it will succeed. We do not predict timelines. See how far each candidate has reached → Why an early-phase trial is not an approval →
Which herpes vaccines are in development?
Programs with a trial currently listed as ongoing include BioNTech's BNT163, a preventive mRNA candidate in Phase 1, and an mRNA vaccine from Changchun BCHT in Phase 1. Earlier programs include therapeutic candidates that completed Phase 2 trials, such as Agenus's HerpV and Vical's VCL-HB01, as well as Moderna's mRNA-1608 (discontinued in November 2025), GSK's Herpevac and Genocea's GEN-003. Full tracker with sources → BNT163 → The BCHT mRNA vaccine →
What is the difference between HSV-1 and HSV-2?
HSV-1 has traditionally caused oral herpes and HSV-2 genital herpes, but either type can infect either site. The distinction matters for vaccines: a candidate can protect against one type and not the other. HSV-1 vs HSV-2 explainer →
What is the difference between a preventive and a therapeutic herpes vaccine?
A prophylactic (preventive) vaccine aims to stop an uninfected person from getting HSV. A therapeutic vaccine is for people already infected, to reduce outbreaks and shedding. They use different trials, endpoints, and populations, and a candidate can target one goal and not the other. Prophylactic vs therapeutic explainer →
Why isn't there a herpes vaccine yet?
HSV establishes lifelong latency in nerve cells and evades parts of the immune response, which makes it a hard vaccine target. Several approaches have reached human trials; none has yet cleared the bar for approval. Why HSV is hard to vaccinate against → What clearing each trial phase would take →