HSV-2 Vaccine and Cure Tracker

If you have been searching for news about a herpes vaccine, you have probably seen a lot of excitement and not many dates. This page is the opposite. It lists every serious HSV-2 vaccine, drug and cure program we could verify, what stage it is really at, and the last time its status changed. Every row links to the trial registry, the company or the journal behind it. We update it every month.

The tracker: every program and where it stands

This is the whole picture in one table. The sections below explain each one in plain English.

Program	What it is	Stage	Status, Sept 2026
Pritelivir (AiCuris)	New kind of antiviral pill	Phase 3 done, filed with FDA	FDA decision Q4 2026
ABI-5366 (Assembly Bio, Gilead)	Once a week antiviral pill	Phase 1b done	Active, Phase 2 next
ABI-1179 (Assembly Bio, Gilead)	Once a week antiviral pill	Phase 1b	Active
BNT163 (BioNTech)	Preventive mRNA vaccine	Phase 1, 318 people	Active, ends Oct 2026
Gene editing (Fred Hutch)	One time treatment to cut the virus out	Mice only	Lab, no human trial yet
mRNA-1608 (Moderna)	Therapeutic mRNA vaccine	Phase 1/2, 303 people	Stopped Nov 2025
GSK3943104 (GSK)	Therapeutic protein vaccine	Phase 2	Stopped Sept 2024

Two words come up a lot below, so here is what they mean. A preventive vaccine is for people who do not have HSV-2 yet and is meant to stop them catching it. A therapeutic vaccine is for people who already have it and is meant to train the immune system to cause fewer outbreaks. Neither kind removes the virus from the nerves.

What happened to the Moderna herpes vaccine

This is the question we get most, so it goes first. Moderna’s herpes vaccine was called mRNA-1608. It was a therapeutic vaccine, built for people who already have HSV-2 and get repeat outbreaks. It went into a Phase 1/2 trial in September 2023 with 303 people and the trial finished on 25 April 2025 (source).

The results were mixed. The vaccine was safe and the immune system clearly responded to it. In exploratory analyses there was a trend toward a longer wait before the next outbreak and fewer outbreaks overall compared with the control shot (source). A trend is not proof, though, and on 20 November 2025 Moderna said it was ending development of mRNA-1608 as part of a wider cut to its pipeline (source).

So if you are still reading posts that say Moderna is “almost releasing” a herpes vaccine, they are out of date. That program is over. Nothing about it is coming to a pharmacy.

GSK stopped too

GSK had its own therapeutic vaccine, GSK3943104, a protein based shot rather than mRNA. It was tested in 240 people with recurrent genital herpes. In September 2024 GSK announced that it failed its main goal, which was to lengthen the time before the next confirmed outbreak, and that it would not move to Phase 3 (source). No safety problems were found. It simply did not work well enough.

That was the second time GSK walked away from a herpes vaccine. The first, Simplirix, was dropped in 2010. The pattern here matters: herpes vaccines have a long history of looking good early and then falling short in bigger trials.

BioNTech BNT163: the last big vaccine standing

BNT163 is a preventive mRNA vaccine, developed by BioNTech with the University of Pennsylvania. Its goal is different from the two above. It is meant to stop people from catching HSV-2 in the first place.

The trial started in December 2022 and enrolled 318 people, some without herpes and some with recurrent genital herpes. It is listed as active but no longer recruiting, with an expected finish in October 2026 (source). That makes it the only major preventive herpes vaccine still in human testing.

Be realistic about what Phase 1 means. It mainly answers two questions: is it safe, and does the immune system respond? It does not tell you whether it actually prevents infection. That needs a much bigger Phase 3 trial, which has not been announced. You will see blogs quoting very specific durability numbers for BNT163. We could not find those numbers in anything BioNTech has published, so we are not repeating them.

The weekly pill that cut shedding by 94%

This is the most interesting result of the past year, and it has had almost no attention outside medical conferences. Assembly Biosciences has two new antiviral pills, ABI-5366 and ABI-1179. Both belong to a newer class called helicase primase inhibitors, which stop the virus copying itself in a different way from Valtrex or acyclovir. The big difference is that they last long enough in the body to be taken once a week instead of every day.

In a Phase 1b trial in people with recurrent genital herpes, the 350 mg once a week dose of ABI-5366 cut HSV-2 shedding by 94% compared with placebo, and cut the rate of confirmed genital lesions by 94% too. The study had aimed for an 80 to 85% cut (source). The company said at the time that it expected to start Phase 2 around mid-2026. Both drugs are now licensed to Gilead, which has the sole right to develop and sell them (source).

Two honest caveats. First, Phase 1b trials are small, and the result has to hold up in bigger ones. Second, this is still suppression, the same idea as daily Valtrex, just less often. It would not cure anyone. But for people who hate remembering a pill every day, and for anyone worried about passing the virus on, a weekly pill with that level of control would be a real change.

Pritelivir: an FDA decision this year

Pritelivir is the only program on this list with an FDA decision date. It is a helicase primase inhibitor from the German company AiCuris. In April 2026 the FDA gave its application Priority Review and set a decision target in the fourth quarter of 2026 (source).

It is aimed at a small group: people with weakened immune systems, such as transplant and cancer patients, whose herpes has stopped responding to standard drugs. In the Phase 3 trial, 82.4% of people on pritelivir had fully healed lesions by day 42, compared with 42.0% on the best available alternative. If it is approved, it will not replace Valtrex for most people with HSV-2. We cover what it could mean for everyone else in our full pritelivir guide.

Gene editing: where the cure research really is

A cure means getting rid of the virus hiding in the nerves, not just keeping it quiet. The most advanced work on that comes from Keith Jerome’s lab at Fred Hutch in Seattle. They send gene editing enzymes to the nerve clusters where herpes sleeps and cut the virus’s DNA.

In mice, the approach removed about 90% of HSV-1 after a facial infection and 97% after a genital infection. The study was published in Nature Communications in May 2024 (source). Two details matter. That work was on HSV-1, and the team is still adapting it for HSV-2. And no person has received it. The researchers have said they are working with regulators and partners toward a first human trial, but they have not given a date.

If you see “CRISPR herpes cure” headlines with a release date on them, ask where the human trial is. Right now there is not one.

When could any of this reach you?

Here is our honest read, based on where each program is today and how long each trial phase usually takes. These are estimates, not promises.

Program	Who it is for	Earliest realistic date
Pritelivir	Immunocompromised people whose herpes resists standard drugs	Late 2026 or 2027, if the FDA approves it
Weekly pills (ABI-5366, ABI-1179)	Anyone who takes suppressive therapy today	Not before about 2029, after Phase 2 and 3
BNT163 vaccine	People who do not have HSV-2 yet	2030s at the earliest, no Phase 3 announced
Gene editing cure	People who already have HSV-2	No date, first human trial not started

What that means for you today: the treatment that works is the one you can get right now. Daily valacyclovir cuts outbreaks and cuts the chance of passing HSV-2 to a partner. Our treatment guide covers how to get it, including online.

Why herpes has been so hard to beat

Around 520 million people aged 15 to 49 have HSV-2 worldwide (source), so this is not a small market that companies ignore. The problem is the biology. After the first infection, the virus goes quiet inside nerve cells near the base of the spine. The immune system mostly cannot see it there, and today’s drugs cannot reach it. Vaccines have to beat a virus that has spent a very long time learning to hide, and so far the ones tested in large trials have not done it.

That is why the programs to watch fall into two groups. Better suppression, like the weekly pills, is closer and more certain. A real cure, like gene editing, is further away and less certain. We will keep this page updated as either one moves.

Related: How herpes vaccines work | Pritelivir guide | Treatment you can get today | Is there a cure for HSV-2?