Zenas BioPharma, Inc.(US:ZBIO)2025-11-18 12:02Summary of Zenas BioPharma Conference Call Company Overview - Company: Zenas BioPharma (NasdaqGS: ZBIO) - Event: Jefferies London Healthcare Conference 2025 - Date: November 18, 2025 Key Points Industry and Pipeline Developments - Zenas BioPharma has expanded its pipeline significantly with new molecules, including obexelimab and rilzabrutinib [2][3] - Obexelimab is concluding a phase three trial in IgG4-related disease, with top-line results expected by the end of the year [3][7] - The company is also advancing a lupus program with 70% enrollment and plans to report a 24-week top-line endpoint in 2026 [3][4] Obexelimab Details - Obexelimab is a novel B cell inhibitor that co-engages CD19 and Fc gamma R2b (CD32b), leading to profound B cell inhibition [4][5] - The phase three trial for IgG4-related disease has shown a dramatic improvement in the IgG4-RI responder index, with a low flare rate of approximately 10% expected compared to a placebo flare rate of 60% [5][7][31] - The trial design is validated by the successful launch of Amgen's OPLISNA, which had a strong market performance [6][7] Market Opportunity - The U.S. market opportunity for IgG4-related disease is estimated at over $3 billion, targeting approximately 30,000-40,000 patients [9][10] - A recent market study indicated a 45% share for obexelimab compared to competitors OPLISNA and rituximab, suggesting strong market potential [10] Rilzabrutinib Insights - Rilzabrutinib is positioned as a best-in-class BTK inhibitor, with a focus on progressive multiple sclerosis (PPMS and SPMS) [11][12] - The drug has shown a 90% reduction in lesions in early studies, with a phase three program already initiated for PPMS [15][24] - The pharmacological profile of rilzabrutinib is highlighted as superior, with a CNS concentration IC90 ratio significantly higher than competitors [14][36] Clinical Trial Design and Strategy - The phase two study for obexelimab in relapsing multiple sclerosis (RMS) demonstrated a 95% risk reduction, setting a new benchmark for B cell targeting [11][19] - The company is optimistic about the transition from RMS to IgG4-related disease, leveraging insights from previous trials to optimize dosing regimens [18][19] - The phase three trial for IgG4-RD is considered overpowered with 194 patients enrolled, compared to 135 in the successful MITIGATE trial [26][31] Future Outlook - Zenas BioPharma anticipates significant milestones in 2026, including results from the IgG4-RD trial and further developments in the lupus program [16][38] - The company is confident in its ability to execute trial designs agreed upon with regulatory agencies, enhancing its position in the competitive landscape of MS treatments [37][36] Additional Considerations - The company is focused on patient preferences for at-home subcutaneous administration, which may lead to better patient compliance and lower costs compared to IV infusions [9][10] - The competitive landscape for BTK inhibitors is evolving, with several companies advancing their products in the MS space, indicating a growing market [35][36] This summary encapsulates the critical insights and developments discussed during the conference call, highlighting Zenas BioPharma's strategic direction and market positioning.