tobevibart
elebsiran Protein Target: HBsAg, hepatitis B surface antigen, HBV RNA, HBV
Vir Biotechnology
Most recent annual filing: 2026-02-15
- VIR-5818 Ph1 readout2H 2026VIR-5818 Ph1 readout, 2H 2026, notable
- ECLIPSE 1 Ph3 topline4Q 2026ECLIPSE 1 Ph3 topline, 4Q 2026, thesis-defining
- ECLIPSE 2 & 3 Ph31Q 2027ECLIPSE 2 & 3 Ph3, 1Q 2027, thesis-defining
- PRO-XTEN TCE preclinical programs corporateearly 2027PRO-XTEN TCE preclinical programs corporate, early 2027, routine
- ECLIPSE 2 and 3 Ph31Q 2027ECLIPSE 2 and 3 Ph3, 1Q 2027, routine
Bar width shows how precise the guidance is — a pin is a stated date, a wide band a six-month window. Deeper blue means more of the thesis rides on the event; it is not a view on the stock.
Pipeline (10 active programs)
VIR-5500
VIR-5818
VIR-5525
HIV bnAb
Technology platforms
dAIsY
Proprietary AI and machine learning-driven antibody optimization platform for engineering therapeutic candidates including TCEs and mAbs for infectious diseases and oncology. Used to optimize potency, resistance, pharmacokinetics, and manufacturability.
PRO-XTEN · Sanofi
Dual-masked T-cell engager platform using XTEN masking technology to keep TCEs inactive until reaching the tumor microenvironment, reducing off-target effects; focus on solid tumor indications including prostate cancer; licensed from Amunix Pharmaceuticals (a Sanofi company), with Vir retaining exclusive oncology and infectious disease rights
Targets: CD3, PSMA, HER2, EGFR
PRO-XTEN · Amunix Pharmaceuticals (a Sanofi company)
Universal dual-masking technology for T-cell engagers; designed to keep TCEs inactive until reaching the tumor microenvironment where tumor-specific proteases cleave the mask; focus areas: oncology solid tumors including prostate, HER2-expressing, and EGFR-expressing cancers; also licensed for infectious disease
Targets: PSMA, HER2, EGFR, CD3
PRO-XTEN · Amunix Pharmaceuticals (Sanofi)
Universal dual-masking technology for T-cell engagers (TCEs) that keeps TCEs inactive until tumor-specific proteases in the tumor microenvironment cleave the mask, activating anti-tumor killing; extends half-life and reduces systemic toxicity; applied across solid tumor indications targeting PSMA, HER2, and EGFR, as well as preclinical candidates in lung, colorectal, and bladder cancer; Vir Biotechnology holds exclusive rights for oncology and infectious disease
Targets: PSMA, CD3, HER2, EGFR
PRO-XTEN · Amunix Pharmaceuticals
Universal dual-masking technology for T-cell engagers (TCEs) that keeps TCEs inactive until reaching the tumor microenvironment, where tumor-specific proteases cleave the mask and activate the TCEs; applied across oncology solid tumor indications including prostate, HER2-positive, and EGFR-expressing tumors; licensed from Amunix Pharmaceuticals (a Sanofi company) with Vir holding exclusive rights for oncology and infectious disease
Targets: PSMA, HER2, EGFR, CD3
PRO-XTEN · Sanofi (via Amunix Pharmaceuticals)
Dual-masking platform technology that keeps T-cell engagers inactive until reaching the tumor microenvironment, reducing off-target effects and improving therapeutic index; focus on solid tumor indications and infectious diseases
Discontinued (1)
- tobevibart — Chronic Hepatitis B · decided not to pursue Phase 3 development of combinations of tobevibart and elebsiran in CHB
Biotech Distilled coverage (5)
- 2026-08-06 UPDATE: Vir Biotechnology (VIR) - Fully Enrolled, and the Competition Just Got Real 🔒 Paid
- 2026-07-24 UPDATE: Vir Biotechnology (VIR) - The CFO Walks, Too 🔒 Paid
- 2026-05-07 UPDATE: Vir Biotechnology (VIR) - The Clean Call (With a $172.5M Footnote) 🔒 Paid
- 2026-04-27 UPDATE: Vir Biotechnology (VIR) - The Astellas Money Lands, the CMO Walks 🔒 Paid
- 2026-03-25 Vir Biotechnology (VIR) - Scientific Deep Dive for Lead and Pipeline Products 🔒 Paid
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