Vor Bio Reports First Quarter 2026 Financial Results and Provides Corporate Update

Enrollment on track for Phase 3 UPSTREAM MG trial of telitacicept in generalized myasthenia gravis patients with topline results anticipated in 1H27

Enrollment ongoing for Phase 3 UPSTREAM SjD of telitacicept in primary Sjögren’s disease

Cash and investment balance of $491.5 million as of March 31, 2026 expected to provide runway into early 2029

BOSTON, May 13, 2026 — Vor Bio (Nasdaq: VOR), a clinical-stage biotechnology company transforming the treatment of autoimmune diseases, today reported financial results for the first quarter ended March 31, 2026, and provided a corporate update.

“We had another quarter of solid execution for our two global Phase 3 programs in generalized myasthenia gravis and primary Sjögren’s disease, both of which are progressing as planned,” said Jean-Paul Kress, M.D., Chief Executive Officer and Chairman of Vor Bio. “Encouragingly, clinician feedback this quarter points to a shift in myasthenia gravis treatment toward broader, more durable disease control through upstream B-cell modulation and targeting multiple pathogenic immunoglobulins, which are central to the BAFF/APRIL mechanism. While efficacy benchmarks in myasthenia gravis are well established, many physicians see the potential for this approach moving earlier in the treatment paradigm, given its potential to change the disease trajectory. Our conviction in telitacicept continues to grow, and we believe it has the potential to become a foundational therapy in B-cell driven autoimmune diseases.”

Program Highlights

Telitacicept: a potential best- and first-in-class dual BAFF/APRIL inhibitor in development for generalized myasthenia gravis (gMG) and primary Sjögren’s disease (SjD)

Generalized Myasthenia Gravis

• UPSTREAM MG Enrollment ongoing in global randomized, double-blind, placebo-controlled Phase 3 registrational trial with an open-label extension assessing the efficacy and safety of telitacicept in gMGTopline data anticipated in 1H 2027

Primary Sjögren’s Disease

• UPSTREAM SjD Enrollment ongoing in global randomized, double-blind, placebo-controlled Phase 3 registrational trial assessing the efficacy and safety of telitacicept in SjD

First Quarter 2026 Financial Results

• Cash Position: Cash, cash equivalents and marketable securities were $491.5 million as of March 31, 2026, which are projected to fund operations into early 2029.
• Research & Development (R&D) Expenses: R&D expenses for the first quarter of 2026 were $17.6 million, compared to $26.7 million for the first quarter of 2025. The decrease of $9.1 million was primarily due to reduced spend on our previous programs, trem-cel and VCAR33, a decrease in personnel costs due to a reduction in headcount compared to the prior year period, and a decrease in various other research and development activities. These decreases were partially offset by the increase in spend for our new programs, telitacicept - gMG and telitacicept - SjD.
• General & Administrative (G&A) Expenses: G&A expenses for the first quarter of 2026 were $17.6 million, compared to $6.6 million for the first quarter of 2025. The increase of $11.0 million was primarily due to increases in stock-based compensation compared to the prior year period. The increase was also attributable to an increase in personnel-related expenses and commercial-related expenses.
• Net Loss: Net loss for the first quarter of 2026 was $219.6 million, compared to $32.5 million net loss for the first quarter of 2025. The increase of $187.1 million was primarily due to the change in fair value of the outstanding liability-classified warrants in the first quarter of 2026.

About Telitacicept

Telitacicept is a novel recombinant fusion protein designed to treat autoimmune diseases through dual inhibition of BLyS (BAFF) and APRIL - two cytokines essential to B cell and plasma cell survival. This dual-target mechanism reduces autoreactive B cells and autoantibody production, key drivers of autoimmune pathology.

Telitacicept is approved in China for systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and generalized myasthenia gravis (gMG). Additional regulatory filings in China are underway, including biologics license applications for primary Sjögren’s disease (SjD) and IgA nephropathy (IgAN).

Vor Bio is advancing global development programs across major autoimmune indications, including a global Phase 3 trial in gMG and SjD, to support potential regulatory approvals in the United States, Europe, and Japan.

About Vor Bio

Vor Bio is a clinical-stage biotechnology company transforming the treatment of autoimmune diseases. The Company is focused on rapidly advancing telitacicept, a novel dual-target fusion protein, through Phase 3 clinical development and potential commercialization to address serious autoantibody-driven conditions worldwide. For more information visit www.vorbio.com.