Telitacicept

Trial met primary endpoint achieving statistically significant improvement in disease activity, with 67.1% of patients responding with telitacicept versus 32.7% with placebo Dual inhibition of BAFF and APRIL validated as a transformative B-cell approach, highlighting telitecicept’s potential as a disease-modifying therapy for systemic lupus erythematosus BOSTON, Oct. 16, 2025 (GLOBE NEWSWIRE) -- Vor Bio (Nasdaq: VOR), a clinical-stage biotechnology company transforming the treatment of autoimmune diseases, today announced that results from a Phase 3 study in China evaluating telitacicept in systemic lupus erythematosus (SLE) sponsored by its collaborator, RemeGen Co., Ltd., (HKEX: 9995, SHA: 688331), were published in The New England Journal of Medicine (NEJM). “We are humbled by what these results represent for patients and the scientific community, and by the recognition that comes with their publication in The New England Journal of Medicine, which underscores the global acceptance of the quality and rigor of clinical research emerging from China. For the first time, a therapy in a Phase 3 trial is delivering more than double the clinical response seen with the current standard of care in lupus. These data present a compelling case for potentially broadening telitacicept’s use as a new standard of care worldwide,” said Jean-Paul Kress, M.D., Chief Executive Officer and Chairman of Vor Bio. “Lupus has challenged researchers and clinicians for decades. To see a dual BAFF/APRIL approach deliver this level of efficacy, durability, and consistency across multiple indications, while maintaining a favorable safety profile, affirms our belief that telitacicept has the potential to redefine how autoimmune diseases are treated.” “These data support the central role of B-cells in the pathobiology of lupus. By targeting both BAFF and APRIL, it was possible to achieve excellent clinical results that suggest the effective restoration of immune balance in at least some of the patients. With this mechanism of action, telitacicept could significantly reduce the burden of lupus,” said Ronald van Vollenhoven, M.D., Ph.D., Professor of Rheumatology at Amsterdam University Medical Center. “This approach could represent an important new addition to the therapeutic landscape for lupus.” The study, conducted at 42 hospitals in China, evaluated telitacicept in 335 patients with active SLE despite standard therapy. The study met its primary endpoint with 67.1% of patients who received telitacicept achieving a modified SLE Responder Index-4 (SRI-4) response compared with 32.7% on placebo (P<0.001) at week 52. More telitacicept-treated patients met a modified SRI-4 response as early as week 4 than those who received placebo. This difference was sustained at week 52. Improvements were also seen across multiple secondary measures: Disease activity: At week 52 SELENA-SLEDAI score reduction from baseline of ≥4 points occurred in 70.1% of the telitacicept group versus 40.5% of placebo patients. The mean change in SELENA-SLEDAI score was -4.95 for telitacicept versus -1.0 for placebo. SELENA-SLEDAI is a 24-item weighted lupus activity score that ranges from 0-105 with higher scores indicating greater disease activity.Physician’s Global Assessment: Greater reductions were observed with telitacicept (-0.79 vs. -0.40).Time to SLE flare: Median time to flare was 198 days on telitacicept versus 115 days on placebo.Steroid dose reduction: The proportion pf patients taking ≤7.5mg/day of glucocorticoid (or prednisone equivalent) or with ≥25% reduction in glucocorticoid dose from baseline over weeks 44-52 was 44.9% in the telitacicept group versus 34.7% for placebo.Kidney involvement: Among patients with baseline proteinuria, more achieved clinically meaningful reductions (71.8% vs. 55.1% on placebo). Safety findings were consistent with previous studies. The most common drug-related adverse events were upper respiratory tract infection (31.7% vs. 19.0% on placebo), injection-site reactions (12.6% vs. 0.6% on placebo), and reductions in immunoglobulin levels. Serious adverse events occurred less frequently with telitacicept (7.2% vs. 14.3% on placebo). About Systemic Lupus Erythematosus (SLE)SLE is a chronic, systemic autoimmune disease that can affect multiple organs and lead to irreversible damage. More than half of patients develop organ injury within 2–6 years of diagnosis. Despite available therapies, including glucocorticoids, antimalarials, immunosuppressants, and biologics, many patients continue to experience active disease, underscoring the urgent need for new treatment options. About TelitaciceptTelitacicept is a novel, investigational recombinant fusion protein designed to treat autoimmune diseases by selectively inhibiting 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. In a Phase 3 clinical trial in generalized myasthenia gravis in China, telitacicept demonstrated a placebo adjusted 4.83-point improvement in MG-ADL (Myasthenia Gravis Activities of Daily Living scale) at 24 weeks, the primary endpoint of the trial. Telitacicept is approved in China for systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and generalized myasthenia gravis (gMG). A global Phase 3 clinical trial in gMG is currently underway across the United States, Europe, South America, and Asia-Pacific to support potential approval in the United States, Europe, and Japan. About Vor BioVor 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. Forward-Looking StatementsThis press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. The words “aim,” “anticipate,” “can,” “continue,” “could,” “design,” “enable,” “expect,” “initiate,” “intend,” “may,” “on-track,” “ongoing,” “plan,” “potential,” “should,” “target,” “update,” “will,” “would,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Forward-looking statements in this press release include Vor Bio’s statements regarding telitecicept’s potential to be a disease-modifying therapy and reduce the burden of systemic lupus erythematosus and to redefine how autoimmune diseases are treated; the potential of the results of the Phase 3 study of telitacicept in systemic lupus erythematosus to broaden telitacicept’s use as a new standard of care worldwide; and the potential of the BAFF - APRIL dual-target mechanism to be an important new addition to the therapeutic landscape for lupus. Vor Bio may not actually achieve the plans, intentions, or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various factors, including the data for our product candidates may not be sufficient for obtaining regulatory approval to commercialize products; we may not be able to execute our business plans, including meeting our planned clinical and regulatory milestones and timelines, and possible limitations of financial and other resources. These and other risks are described in greater detail under the caption “Risk Factors” included in Vor Bio’s most recent annual or quarterly report and in other reports it has filed or may file with the Securities and Exchange Commission. The results of the clinical trial described in this press release is based on information reported by RemeGen; Vor Bio has not independently verified this data. Any forward-looking statements contained in this press release speak only as of the date hereof, and Vor Bio expressly disclaims any obligation to update any forward-looking statements, whether because of new information, future events or otherwise, except as may be required by law. Vor Media & Investor Contacts:Carl Mauchcmauch@vorbio.com Sarah Spencerinvestors@vorbio.com

Telitacicept met primary and all secondary endpoints, demonstrating clinically meaningful improvements in disease activity versus placebo ~71.8% of patients receiving telitacicept 160mg achieved ≥3-point ESSDAI (EULAR Sjögren’s Syndrome Disease Activity Index) reduction vs 19.3% on placebo at 24 weeks Sustained efficacy and favorable safety profile through 48 weeks support potential best-in-disease profile in primary Sjögren’s disease (pSD) Company evaluating timing of global Phase 3 clinical study in primary Sjögren's diseaseVor Bio to host a conference call on Tuesday, October 28, 2025 at 4:30PM ET BOSTON, Oct. 14, 2025 (GLOBE NEWSWIRE) -- Vor Bio (Nasdaq: VOR), a clinical-stage biotechnology company transforming the treatment of autoimmune diseases, today announced that its collaborator, RemeGen Co., Ltd (HKEX: 9995, SHA: 688331), reported positive 48-week results from its Phase 3 study conducted in China evaluating telitacicept in primary Sjögren’s disease. The study met its primary endpoint of change from baseline in ESSDAI at week 24, as well as all secondary endpoints, with the telitacicept 160mg dose achieving highly significant p values (p<0.0001) for every endpoint at week 24 and 48 compared to placebo. The results will be presented in the late-breaking poster session at the American College of Rheumatology (ACR) Convergence 2025 on October 28, 2025 from 10:30am to 12:30pm CT in Chicago, Illinois.“With today’s Phase 3 results in primary Sjögren’s disease, we are thrilled to announce that telitacicept is demonstrating disease-modifying potential in a condition that has long lacked any approved treatment. We believe these are clear data which can help pave a path towards a brighter future for this deserving community. The consistency of benefit through 48 weeks, together with a reassuring safety profile, supports telitacicept’s potential to become the first treatment that addresses the root biology of Sjögren’s disease rather than managing symptoms alone,” said Jean-Paul Kress, M.D., Chief Executive Officer and Chairman of Vor Bio. “Based on these promising results, we are evaluating the timing of a global Phase 3 clinical study in primary Sjögren’s disease, which represents a significant opportunity to expand into and bring telitacicept’s benefits to patients worldwide.” “Primary Sjögren’s disease represents a substantial unmet need in rheumatology, with patients facing years of fatigue, pain, and systemic complications without a truly effective therapy,” said Ronald van Vollenhoven, M.D., Ph.D., Professor of Rheumatology at Amsterdam University Medical Center. “I am impressed how these data show that dual BAFF/APRIL inhibition with telitacicept could offer a clear impact on both disease activity and patient-reported outcomes.” The China Phase 3 trial was a randomized, double-blind, placebo-controlled trial in patients with active, anti-SSA-positive primary Sjögren’s disease. A total of 381 patients were randomized to receive weekly subcutaneous injections of telitacicept 160mg, telitacicept 80mg, or placebo for 48 weeks, in addition to standard therapy. During weeks 24-48, participants with inadequate response to treatment in the placebo group could switch to telitacicept 160mg or telitacicept 80mg at a ratio of 1:1 under blind conditions. The primary endpoint of the study was change from baseline in ESSDAI at week 24, with secondary endpoints including changes in ESSDAI and ESSPRI (EULAR Sjögren’s Syndrome Patient Reported Index) at 12, 24, 36, and 48 weeks, as well as the proportion of patients achieving clinically meaningful improvements (≥3-point decrease in ESSDAI and achievement of low disease activity [ESSDAI <5]) at 24 and 48 weeks. Key Findings from the 48-Week Results Mean change in ESSDAI: At week 24, -4.4 (160mg), -3.0 (80mg), and -0.6 (placebo); at week 48, -4.6 (160mg), -3.2 (80mg), and -0.4 (placebo), demonstrating durable, dose-dependent improvement in systemic disease activity.Mean change in ESSPRI: At week 24, -1.88 (160mg), -1.31 (80mg), and -0.36 (placebo); at week 48, -2.56 (160mg), -1.74 (80mg), and -0.41 (placebo), showing sustained symptomatic benefit in dryness, fatigue, and pain.≥3-point ESSDAI improvement: At week 24, 71.8% (160mg), 47.1% (80mg), and 19.3% (placebo); at week 48, 73.0% (160 mg), 49.1% (80mg), and 16.5% (placebo).Participants with ESSDAI <5 (low disease activity): At week 24, 49.6% (160mg), 28.8% (80mg), and 10.9% (placebo); at week 48, 55.0% (160mg), 32.7% (80mg), and 12.2% (placebo).Participants with ≥1-point or ≥15% ESSPRI reduction: At week 24, 86.2% (160mg), 63.0% (80mg), and 32.2% (placebo); at week 48, 89.1% (160mg), 75.4% (80mg), and 33.3% (placebo).Change from baseline in MFI-20 total (fatigue): At weeks 24 and 48, telitacicept 160mg produced a statistically significant and clinically meaningful reduction in fatigue versus 80mg and placebo, with improvements sustained through the open-label extension.Telitacicept demonstrated a favorable safety profile comparable to placebo and consistent with prior studies across other autoimmune indications, including systemic lupus erythematosus, rheumatoid arthritis, myasthenia gravis, and IgA nephropathy. No new safety signals were observed. Most adverse events were mild to moderate in severity. About Sjögren’s Disease (formerly known as Sjögren’s Syndrome)Sjögren’s disease is a chronic autoimmune condition in which overactive B cells drive inflammation, damaging moisture-producing glands and, in many cases, other organs. Hallmark symptoms include dry eyes and dry mouth, alongside fatigue, pain, and systemic complications affecting the skin, lungs, kidneys, and nervous system. About one-third of patients develop significant extraglandular involvement, and the disease carries an elevated lymphoma risk, often leading to substantial impairment in daily life. One of the most common rheumatic autoimmune diseases, Sjögren’s remains underdiagnosed, with roughly half of cases unrecognized and women comprising the vast majority of patients. Despite its prevalence and burden, no systemic disease-modifying therapies exist; current care focuses on symptom management with incomplete relief. About TelitaciceptTelitacicept is a novel, investigational recombinant fusion protein designed to treat autoimmune diseases by selectively inhibiting 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. In a Phase 3 clinical trial in generalized myasthenia gravis in China, telitacicept demonstrated a placebo adjusted 4.83-point improvement in MG-ADL (Myasthenia Gravis Activities of Daily Living scale) at 24 weeks, the primary endpoint of the trial. Telitacicept is approved in China for systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and generalized myasthenia gravis (gMG). A global Phase 3 clinical trial in gMG is currently underway across the United States, Europe, South America, and Asia-Pacific to support potential approval in the United States, Europe, and Japan. About Vor BioVor 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. Forward-Looking StatementsThis press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. The words “aim,” “anticipate,” “can,” “continue,” “could,” “design,” “enable,” “expect,” “initiate,” “intend,” “may,” “on-track,” “ongoing,” “plan,” “potential,” “should,” “target,” “update,” “will,” “would,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Forward-looking statements in this press release include Vor Bio’s statements regarding the potential of telitacicept in primary Sjögren’s disease, including the potential to have a best-in-class profile, to be disease-modifying, to become the first treatment that addresses the root biology of Sjögren’s disease rather than managing symptoms alone, and offer a clear impact on both disease activity and patient-reported outcomes; our belief that the Phase 3 Primary Sjögren’s data are clear data which can help pave a path towards a brighter future for this deserving community; telitacicept’s market opportunity in primary Sjogren’s disease; the possibility of Vor Bio initiating a global Phase 3 clinical study in primary Sjögren’s disease; the timing of presentation of clinical data; Vor Bio’s development and commercialization plans for telitacicept; and other statements that are not historical fact. Vor Bio may not actually achieve the plans, intentions, or expectations disclosed in these forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in these forward-looking statements as a result of various factors, including the data for our product candidates may not be sufficient for obtaining regulatory approval to commercialize products; we may not be able to execute our business plans, including meeting our planned clinical and regulatory milestones and timelines, and possible limitations of financial and other resources. These and other risks are described in greater detail under the caption “Risk Factors” included in Vor Bio’s most recent annual or quarterly report and in other reports it has filed or may file with the Securities and Exchange Commission. The results of the clinical trial described in this press release is based on information reported by RemeGen; Vor Bio has not independently verified this data. Any forward-looking statements contained in this press release speak only as of the date hereof, and Vor Bio expressly disclaims any obligation to update any forward-looking statements, whether because of new information, future events or otherwise, except as may be required by law. Media & Investor Contacts: Carl Mauch cmauch@vorbio.com Sarah Spencer investors@vorbio.com