Breaking
Antiva ABI-2280 posts positive Phase 1b/2 top-line data 46% HPV negativity vs 16% placebo at week 12 87% of responders still HPV-negative at week 24 $53M Series E led by MPM-BioImpact Capital Kristine Ball named President & CEO Data presented at SGO 2026 Still no approved treatment for HPV infection - Antiva aims to change that Antiva ABI-2280 posts positive Phase 1b/2 top-line data 46% HPV negativity vs 16% placebo at week 12 87% of responders still HPV-negative at week 24 $53M Series E led by MPM-BioImpact Capital Kristine Ball named President & CEO Data presented at SGO 2026 Still no approved treatment for HPV infection - Antiva aims to change that
Clinical-Stage Biopharma • South San Francisco, CA

Antiva Biosciences

A tablet, not an operating room. Antiva is developing the first drug to actually treat HPV - the virus behind most cervical cancer.

Founded 2012 ~18 Employees Series E Women's Health
Antiva Biosciences logo
Antiva Biosciences, Inc. - the South San Francisco team betting a decade-plus of prodrug chemistry on a self-administered HPV therapy.
What They Do

Treating a virus the medical system can only prevent or cut out

HPV - human papillomavirus - is one of the most common infections in the world and the cause of nearly all cervical cancer. Yet for a disease this widespread, the medical toolkit has a strange gap: there are vaccines to prevent HPV and there is surgery to remove the lesions it leaves behind, but there is no approved drug to treat the infection itself. Antiva Biosciences exists to close that gap.

Founded in 2012 on lipophilic prodrug chemistry developed by Dr. Karl Hostetler at UC San Diego, Antiva builds topical antiviral therapeutics that a patient can administer herself. The lead candidate, ABI-2280, is formulated as a vaginal tablet. It is designed to block HPV DNA replication and push infected cells toward apoptosis - clearing the virus and the pre-cancerous lesions it drives.

The target patients are women with high-risk HPV infection and high-grade cervical intraepithelial neoplasia (CIN 2,3), the pre-cancerous stage that today is typically managed with watchful waiting or surgical excision. Antiva's premise is simple to state and hard to deliver: intercept the disease earlier, at home, before it ever becomes cancer or requires a procedure that can affect a woman's ability to carry a pregnancy.

It is a clinical-stage company, meaning its product is still in trials rather than on pharmacy shelves. But the direction is unusual in a field crowded with prevention and screening - Antiva is squarely focused on the treatment step that everyone agrees is missing.

The Problem, In Numbers

Why this matters

HPV is not a rare disease. It is a routine one that becomes deadly when nothing intervenes between infection and cancer.

5.5M+
U.S. women with high-risk HPV each year
604K
Cervical cancer cases worldwide (2020)
342K
Cervical cancer deaths worldwide (2020)
0
Approved drugs to treat HPV infection today
The Evidence

What the Phase 1b/2 data showed

In a 139-patient study of women aged 25-55 with a documented high-risk HPV infection, ABI-2280 met its primary endpoint. The gap between drug and placebo is the whole story.

HPV negativity at Week 12

ABI-2280 vs placebo • primary endpoint
ABI-2280
46%
Placebo
16%

Durability: 87% of patients who cleared HPV at week 12 stayed negative at week 24. Treatment was reported safe and well tolerated, with mild-to-moderate events localized to the treatment area.

Figures are approximate top-line results as reported by the company; see sources.

Pipeline & Products

The molecules

Lead • Phase 1b/2

ABI-2280

A topical, self-administered vaginal tablet built from a lipophilic antiviral prodrug. It blocks HPV replication and induces apoptosis in infected cells, targeting both high-risk HPV infection and high-grade cervical lesions (CIN 2,3).

Prior lead

ABI-1968

The earlier topical antiviral prodrug, evaluated in Phase 1b studies for high-grade cervical and anal dysplasia before the program advanced to the more potent ABI-2280.

The design principle

At-home by intent

Formulating the therapy as a tablet a woman uses herself is a deliberate access choice - it reaches patients far from gynecologic surgery and fits the WHO's screen-and-treat model.

"ABI-2280 can make the World Health Organization's screen-and-treat approach to HPV infection a reality." Dr. Florencia Segal, Antiva Biosciences
How It's Different

Where Antiva sits in the market

The alternatives to Antiva are not really rival drugs - they are the absence of one. Prevention is handled by HPV vaccines like Gardasil, but a vaccine does nothing for the millions of women already infected. Once a lesion appears, care means watchful waiting or a surgical procedure (LEEP, conization, cryotherapy) that removes tissue and can carry risks to future fertility.

Antiva's differentiation is the category itself: a medicine that treats the infection rather than preventing it or excising its consequences. If ABI-2280 is approved, it would be the first drug of its kind. That is both the opportunity and the risk - there is no established regulatory or commercial path to follow, because nothing has walked it before.

Commercially, Antiva runs the classic venture-backed biotech model: raise equity, advance the science through trials, and create value by moving the lead candidate toward approval or partnership. With roughly 18 employees, it is a lean organization pointed at a single, large problem.

Its expertise is concentrated where it counts - antiviral prodrug chemistry, topical drug delivery, and gynecologic clinical development - backed by investors who specialize in life sciences and global health, including MPM-BioImpact Capital, Sofinnova, Canaan, GV, Adjuvant Capital and Lumira Ventures.

"ABI-2280 has tremendous potential to play a significant role in advancing global health and women's health." Kristine Ball, President & CEO
Funding

~$142M across four rounds

A fourteen-year build is expensive. Here is the capital that has gone into the bet.

$22M
Series C • 2017
$15M
Series C-1 • 2018
$31M
Series D • 2021
$53M
Series E • 2023

Series E led by MPM-BioImpact Capital, with Canaan Partners, Sofinnova Investments, Adjuvant Capital, GV and Lumira Ventures.

Timeline

From a UC San Diego lab to Phase 2

2012

Company founded

Antiva is founded in South San Francisco on lipophilic prodrug science from Dr. Karl Hostetler at UC San Diego.

2017

$22M Series C

Closes a Series C to advance its topical HPV antiviral program.

2018

$15M Series C-1

Adds a Series C-1 extension to fund clinical development.

2021

$31M Series D

Raises a Series D to push ABI-2280 into the clinic.

2022

Global Women's Health award

Recognized as a winner of a Global Women's Health innovation award.

2023

$53M Series E & new CEO

Kristine Ball becomes President & CEO; Gail Maderis moves to Board Chair.

2025

Positive Phase 1b/2 top-line data

46% HPV negativity vs 16% placebo at week 12, with 87% durability at week 24.

2026

SGO 2026 presentation

Presents the ABI-2280 dataset at the Society of Gynecologic Oncology Annual Meeting.

Details Worth Knowing

A few things that stand out

FAQ

Questions people ask

What does Antiva Biosciences do?

It develops topical, self-administered antiviral therapeutics for diseases caused by HPV, aiming to clear infection and treat pre-cancerous cervical lesions without surgery.

What is ABI-2280?

Antiva's lead candidate: a vaginal tablet made from a lipophilic antiviral prodrug that blocks HPV replication and induces apoptosis in infected cells. It is in Phase 1b/2 trials.

Has ABI-2280 shown results?

Yes. In a Phase 1b/2 study of 139 patients, 46% achieved HPV negativity at 12 weeks versus 16% on placebo, and 87% of responders remained negative at 24 weeks.

How is Antiva funded?

Through venture financing - roughly $142M across Series C through E, including a $53M Series E in April 2023 led by MPM-BioImpact Capital.

Who leads the company?

Kristine Ball is President & CEO (since April 2023). Gail Maderis, the prior CEO, serves as Board Chair. Antiva was scientifically founded by Dr. Karl Hostetler.

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