XmAb-541

-- XmAb819, novel first-in-class ENPP3 x CD3 T-cell engaging bispecific antibody, Phase 1 dose expansion in CRC, NSCLC and pRCC open to enrollment; on track to present clinical data to support a recommended Phase 3 dose in ccRCC in 2H26 -- -- Final results from healthy-volunteer study of Xmb942, Xtend™ TL1A antibody, and preclinical characterization of XmAb412, TL1A x IL23p19 XmAb® bispecific antibody, to be presented at DDW 2026 -- PASADENA, Calif.--(BUSINESS WIRE)--Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered antibodies for the treatment of cancer and autoimmune diseases, today reported financial results for the fourth quarter and full year ended December 31, 2025. “Xencor’s lead oncology drug candidate is XmAb819, a novel first-in-class T-cell engager that could offer a much-needed new therapeutic modality for patients with advanced clear cell renal cell carcinoma (ccRCC). Excitement from the clinical community on our initial data from the dose-escalation study presented during ENA 2025 supports achieving our goal of presenting dose-expansion data during a medical meeting in the second half of 2026 and our plans to initiate a pivotal study during 2027,” said Bassil Dahiyat, Ph.D., president and chief executive officer at Xencor. “Building on the early success in ccRCC, we recently opened additional dose expansion cohorts in other tumor types that have high ENPP3 expression: colorectal cancer, non-small cell lung cancer and papillary renal cell carcinoma.” “In 2026, we plan to present additional key clinical data and progress updates as we also advance XmAb541 and our ongoing B-cell depleting autoimmune programs, respectively. Our TL1A pipeline in inflammatory bowel disease continues to advance, as well. We are making great progress with enrollment in our Phase 2b XENITH-UC study of XmAb942 and are excited to begin the first-in-human study of XmAb412, our novel TL1A x IL23p19 bispecific antibody in the second half of 2026. We are proud of our execution across an evolved clinical pipeline and of the Xencor team’s focus on designing proteins to deliver novel medicines for patients.” Wholly Owned Pipeline Overview XmAb819 (ENPP3 x CD3), a first-in-class, tumor-targeted T-cell engaging XmAb® 2+1 bispecific antibody in development for patients with advanced clear cell renal cell carcinoma (ccRCC). The dose-expansion portion of the ongoing Phase 1 study is enrolling patients and dose-optimization continues. Tumor expansion cohorts in colorectal cancer (CRC), non-small cell lung cancer (NSCLC) and papillary renal cell carcinoma (pRCC) are now open to enrollment. Xencor plans to present new clinical data to support a recommended Phase 3 dose in 2H26 and initiate a pivotal study of XmAb819 in ccRCC during 2027. XmAb541 (CLDN6 x CD3), a first-in-class, tumor-targeted T-cell engaging XmAb 2+1 bispecific antibody in Phase 1 clinical development for patients with advanced gynecologic and germ cell tumors. Xencor plans to present new clinical data to support a recommended Phase 3 dose in 2H26 and evaluate plans for a pivotal study of XmAb541 during 2027. XmAb942 (Xtend™ anti-TL1A), a potential best-in-class, high-potency, extended half-life antibody in development for patients with inflammatory bowel disease. Xencor is conducting the global XENITH-UC Study, a Phase 2b study of XmAb942 in ulcerative colitis (UC). XENITH-UC is a randomized, double-blind, placebo-controlled trial in patients with moderate-to-severe UC, whose disease has progressed after at least one conventional or advanced therapy. Xencor is on-track to present final results from the Phase 1 study of XmAb942 in healthy volunteers in a poster titled “XmAb942, a Potential Best-in-class, Long-acting Anti-TL1A Antibody for the Treatment of Inflammatory Bowel Disease: Phase 1 Final Results” at Digestive Disease Week® (DDW), being held May 2-5, 2026 in Chicago and online, and to provide an update on progress achieved in the XENITH-UC study around year-end 2026. XmAb412 (TL1A x IL23p19), a bispecific antibody for dual targeting of important inflammatory pathways in autoimmune and inflammatory disease, while avoiding the complexities of dosing and formulary access for two separate TL1A and IL23 targeted drugs. Xencor is on track to present the preclinical characterization of XmAb412 in a poster titled “Discovery and Characterization of XmAb412: A Novel, High-Affinity, Anti-TL1A x Anti-IL23 Native-like Bispecific Antibody With Extended Half-life for the Treatment of Inflammatory Bowel Disease” at DDW in May 2026 and to initiate a first-in-human study of XmAb412 in 2H26. Plamotamab (CD20 x CD3), a clinical-stage, B-cell depleting bispecific T-cell engager in Phase 1 development for patients with rheumatoid arthritis (RA), who have progressed through prior standard-of-care treatment. Xencor plans to provide an update on progress achieved in the Phase 1b study of plamotamab in RA in 2H26. XmAb657 (CD19 x CD3), a clinical-stage, potent, extended half-life B-cell depleting bispecific T-cell engager in Phase 1 development for patients with idiopathic inflammatory myopathies (IIM). Xencor plans to provide an update on progress achieved in the Phase 1 study of XmAb657 in 2H26. XmAb808 (B7-H3 x CD28), a bispecific antibody designed to provide conditional co-stimulation of T cells when also bound to tumor cells. Xencor plans to present a poster characterizing preclinical combinations of XmAb808 with multiple CD3 T cell engaging bispecific antibodies at a medical meeting in 1H26. Xtend U.S. Patent Term Extension: In December 2025, Xencor announced the issuance of U.S. Patent 12,492,253 , which covers Xencor’s Xtend Fc domain for extending the half-life of antibodies targeting C5, with a term that extends into December 2028. Xencor anticipates receiving low-single digit royalties on net sales of Ultomiris® (ravulizumab-cwvz), an anti-C5 antibody engineered with a licensed Xtend Fc domain, into December 2028 in the United States. Ultomiris is a drug being developed and commercialized by Alexion Pharmaceuticals, Inc., and is a registered trademark of Alexion. Xencor previously secured regulatory extensions of exclusivity in several EU countries, Japan and Australia. Based upon consensus sales forecasts, Xencor estimates recognizing potential royalty revenue in excess of the caps under its royalty agreement with OMERS in the range of $100 million to $120 million in aggregate for the extended patent term through 2028. Financial Guidance: Based on current operating plans, Xencor expects to end 2026 with between $400 million and $430 million in cash, cash equivalents and marketable debt securities, and to have sufficient cash resources to fund research and development programs and operations through 2028. Financial Results for the Fourth Quarter and Full Year Ended December 31, 2025 Cash, cash equivalents, and marketable debt securities totaled $610.8 million as of December 31, 2025 compared to $706.7 million as of December 31, 2024. Total revenue for the fourth quarter ended December 31, 2025 was $28.2 million compared to $52.8 million for the same period in 2024. Revenue for the full year ended December 31, 2025 was $125.6 million compared to $110.5 million for the same period in 2024. The increase in revenue in 2025 compared to 2024 was primarily driven by revenue recognition associated with Alexion and Incyte license agreements. Research and development (R&D) expenses for the fourth quarter ended December 31, 2025 were $64.8 million compared to $51.1 million for the same period in 2024. R&D expenses for the full year ended December 31, 2025 were $239.4 million compared to $227.7 million for the same period in 2024. Increased R&D expenses in 2025 compared to 2024 were primarily driven by higher external and internal costs associated with pipeline programs, partially offset by lower stock-based compensation expense. General and administrative (G&A) expenses for the fourth quarter ended December 31, 2025 were $17.0 million compared to $14.9 million for the same period in 2024. G&A expenses for the full year ended December 31, 2025 were $63.6 million compared to $61.2 million for the same period in 2024. G&A expenses in 2025 compared to 2024 remained relatively consistent. Other income, net for the fourth quarter ended December 31, 2025 was $49.4 million compared to other expense, net of $31.4 million for the same period in 2024. Other income, net for the full year ended December 31, 2025 was $87.9 million compared to other expense, net of $56.5 million in the same period in 2024. Other income, net, in 2025 compared to other expense, net, in 2024 was primarily driven by a combination of realized and unrealized gains from marketable equity securities. Net loss attributable to Xencor for the fourth quarter ended December 31, 2025 was $6.7 million or $(0.09) on a fully diluted per share basis compared to net loss of $45.6 million or $(0.62) on a fully diluted per share basis, for the same period in 2024. For the full year ended December 31, 2025 net loss attributable to Xencor was $91.9 million or $(1.24) on a fully diluted per share basis compared to net loss of $232.6 million or $(3.58) on a fully diluted per share basis, for the same period in 2024. About Digestive Disease Week® Digestive Disease Week® (DDW) is the largest international gathering of physicians, researchers, and academics in the fields of gastroenterology, hepatology, endoscopy, and gastrointestinal surgery. Jointly sponsored by the American Association for the Study of Liver Diseases (AASLD), the American Gastroenterological Association (AGA), the American Society for Gastrointestinal Endoscopy (ASGE), and the Society for Surgery of the Alimentary Tract (SSAT), DDW is an in-person and online meeting. Digestive Disease Week® is a registered trademark of DDW, LLC. About Xencor Xencor is a clinical-stage biopharmaceutical company developing engineered antibodies for the treatment of patients with cancer and autoimmune diseases. More than 20 candidates engineered with Xencor's XmAb® technology are in clinical development, and multiple XmAb medicines are marketed by partners. Xencor's XmAb engineering technology enables small changes to a protein’s structure that result in new mechanisms of therapeutic action. For more information, please visit . Forward-Looking Statements Certain statements contained in this press release may constitute forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include statements that are not purely statements of historical fact, and can generally be identified by the use of words such as “potential,” “can,” “will,” “plan,” “may,” “could,” “would,” “expect,” “anticipate,” “seek,” “look forward,” “believe,” “committed,” “investigational,” “indicates,” “supports,” and similar terms, or by express or implied discussions relating to Xencor’s business, including, but not limited to, statements regarding our expectations regarding regulatory and partnership milestone achievements, clinical pipeline advancements , planned receipt and presentations of clinical data, including the expected timing thereof, and planned and ongoing clinical trials, including the expected timing thereof, projected financial resources and financial guidance, including estimated cash, cash equivalents and marketable debt securities at year end and cash runway for research and development programs and operations, expectations for and estimates of future royalty revenues, the quotations from Xencor's president and chief executive officer, and other statements that are not purely statements of historical fact. Such statements are made on the basis of the current beliefs, expectations, and assumptions of the management of Xencor and are subject to significant known and unknown risks, uncertainties and other factors that may cause actual results, performance or achievements and the timing of events to be materially different from those implied by such statements, and therefore these statements should not be read as guarantees of future performance or results. Such risks include, without limitation, the risks associated with the process of discovering, developing, manufacturing and commercializing drugs that are safe and effective for use as human therapeutics, the ability of publicly disclosed preliminary clinical trial data to support continued clinical development and regulatory approval for specific treatments, the risk of loss of key members of management, the risk that the fair value of our marketable equity securities will decline and the risks, uncertainties and other factors described under the heading “Risk Factors” in Xencor's Annual Report on Form 10-K for the year ended December 31, 2025 as well as Xencor's subsequent filings with the Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. Xencor undertakes no obligation to revise or update these forward-looking statements to reflect events or circumstances after the date hereof, except as required by law. Xencor, Inc. Selected Consolidated Balance Sheet Data (in thousands) December 31, December 31, 2025 2024 Cash, cash equivalents and marketable debt securities - current $ 435,231 $ 449,846 Other current assets 164,590 127,755 Marketable debt securities - long term 175,602 256,833 Other long-term assets 100,072 117,511 Total assets $ 875,495 $ 951,945 Total current liabilities $ 95,907 87,432 Liabilities related to the sales of future royalties - long term 76,482 115,159 Other long-term liabilities 67,519 75,328 Total liabilities 239,908 277,919 Total stockholders' equity 635,587 674,026 Total liabilities and stockholders’ equity $ 875,495 $ 951,945 Xencor, Inc. Consolidated Statements of Operations and Comprehensive Loss (in thousands, except per share amounts) Three Months Ended December 31, Year Ended December 31, 2025 2024 2025 2024 Revenue Collaborations, milestones, and royalties $ 28,237 $ 52,794 $ 125,576 $ 110,493 Operating expenses: Research and development 64,824 51,056 239,434 227,686 General and administrative 17,041 14,916 63,644 61,215 Total operating expenses 81,865 65,972 303,078 288,901 Operating loss (53,628 ) (13,178 ) (177,502 ) (178,408 ) Total other income (expense) 49,362 (31,404 ) 87,869 (56,515 ) Loss before income tax expense and noncontrolling interest (4,266 ) (44,582 ) (89,633 ) (234,923 ) Income tax expense 2,387 1,617 2,504 1,617 Net loss including noncontrolling interest (6,653 ) (46,199 ) (92,137 ) (236,540 ) Net loss attributable to noncontrolling interest — (647 ) (214 ) (3,922 ) Net loss attributable to Xencor, Inc. $ (6,653 ) $ (45,552 ) $ (91,923 ) $ (232,618 ) Net loss per share attributable to Xencor, Inc. (basic and diluted) $ (0.09 ) $ (0.62 ) $ (1.24 ) $ (3.58 ) Weighted-average shares used in calculating net loss per share (basic and diluted) 74,586 73,176 74,239 65,041 Other comprehensive income (loss), net of tax: Net unrealized gain (loss) on marketable debt securities 418 (2,464 ) 2,239 (1,954 ) Comprehensive loss (6,235 ) (48,663 ) (89,898 ) (238,494 ) Less: comprehensive loss attributable to the noncontrolling interest — (647 ) (214 ) (3,922 ) Comprehensive loss attributable to Xencor, Inc. $ (6,235 ) $ (48,016 ) $ (89,684 ) $ (234,572 ) Contacts For Investors: Charles Liles cliles@xencor.com (626) 737-8118 For Media: Cassidy McClain Inizio Evoke cassidy.mcclain@inizioevoke.com (619) 694-6291

PASADENA, Calif.--(BUSINESS WIRE)--Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered antibodies for the treatment of cancer and autoimmune diseases, today announced corporate priorities and 2026 pipeline advancement milestones for its clinical-stage portfolio of novel XmAb® drug candidates. “Xencor designs proteins that enable potential first-in-class and best-in-class medicines for patients, and we are building on momentum from 2025, when we presented encouraging clinical data from our portfolio of T-cell engagers and TL1A antibodies,” said Bassil Dahiyat, Ph.D., president and chief executive officer at Xencor. “We are excited to be evaluating a pipeline of five wholly owned clinical-stage XmAb drug candidates and have plans this year to begin the first-in-human study of our TL1A x IL23p19 bispecific antibody for development in inflammatory bowel disease.” “Throughout 2026, we plan to present key clinical data and program updates as we advance our oncology programs toward late-stage development and present clinical proof-of-concept data for our autoimmune programs. We are also starting the year with a strong balance sheet to execute our plans, and we look forward to several updates, potential regulatory achievements and milestones across multiple partner programs.” Four Novel XmAb® T-Cell Engagers in Solid Tumor Oncology and B-Cell Depletion for Autoimmune Disease XmAb819 (ENPP3 x CD3), a novel, first-in-class, tumor-targeted T-cell engaging XmAb® 2+1 bispecific antibody in development for patients with advanced clear cell renal cell carcinoma (ccRCC). Initial results from an ongoing Phase 1 study in advanced ccRCC indicated that XmAb819 demonstrated evidence of anti-tumor activity and an acceptable safety pro was generally well tolerated. Of the 20 efficacy-evaluable patients treated at the dose levels that were preclinically predicted to be within the target dose range, 25% achieved a partial response (RECIST v1.1) as best response with a 70% disease control rate. The dose-expansion portion of the ongoing Phase 1 study is enrolling patients and dose-escalation continues. We plan to: Present new clinical data to support a recommended Phase 3 dose in 2H26 Initiate tumor expansion cohorts in colorectal cancer (CRC), non-small cell lung cancer (NSCLC) and papillary renal cell carcinoma (pRCC) during 2026 Initiate a pivotal study of XmAb819 in ccRCC during 2027 XmAb541 (CLDN6 x CD3), a novel, first-in-class, tumor-targeted T-cell engaging XmAb 2+1 bispecific antibody in development for patients with advanced gynecologic and germ cell tumors. In 2025, Xencor presented early efficacy data from a cohort in the ongoing Phase 1 dose-escalation study of XmAb541. Nine patients had received XmAb541 in the most recently completed escalation cohort. Confirmed partial responses (RECIST v1.1) were observed in three patients: one patient with ovarian cancer and two patients with germ cell tumors. We plan to: Present new clinical data to support a recommended Phase 3 dose in 2H26 Initiate a pivotal study of XmAb541 during 2027 Plamotamab (CD20 x CD3), a clinical-stage, B-cell depleting bispecific T-cell engager in development for patients with rheumatoid arthritis (RA). Xencor is evaluating plamotamab in an ongoing Phase 1b proof-of-concept study, for patients with RA who have progressed through prior standard-of-care treatment. We plan to: Provide an update on progress achieved in the Phase 1b study of plamotamab in RA in 2H26 XmAb657 (CD19 x CD3), a clinical-stage, potent, extended half-life B-cell depleting bispecific T-cell engager in development for patients with idiopathic inflammatory myopathies (IIM). In the fourth quarter of 2025, Xencor initiated a Phase 1 proof-of-concept study of XmAb657 for patients with IIM. We plan to: Provide an update on progress achieved in the Phase 1 study of XmAb657 in 2H26 Two Differentiated, Potentially Best-in-Class Therapeutic Options for Inflammatory Bowel Disease XmAb942 (Xtend™ anti-TL1A), a potential best-in-class, high-potency, extended half-life antibody in development for patients with inflammatory bowel disease. Xencor is conducting the global XENITH-UC Study, a Phase 2b study of XmAb942 in ulcerative colitis (UC). XENITH-UC is a randomized, double-blind, placebo-controlled trial in patients with moderate-to-severe UC, whose disease has progressed after at least one conventional or advanced therapy. Patient enrollment in the study is ongoing. We plan to: Present final results from the Phase 1 study of XmAb942 in healthy volunteers in 1H26 Provide an update on progress achieved in the XENITH-UC study near year-end 2026 XmAb412 (TL1A x IL23p19), a bispecific antibody for dual targeting of important inflammatory pathways in autoimmune and inflammatory disease, while avoiding the complexities of dosing and formulary access for two separate TL1A and IL23 targeted drugs. XmAb412 was selected as the lead candidate in 2025. We plan to: Present preclinical characterization of XmAb412 in 1H26 Initiate a first-in-human study of XmAb412 in 2H26 Preliminary Cash Position and Financial Guidance Xencor’s broad development portfolio is supported by a strong financial position. Xencor ended the fourth quarter of 2025 with unaudited cash, cash equivalents and marketable debt securities expected to be approximately $611 million. Based on current operating plans, Xencor expects to have sufficient cash resources to fund research and development programs and operations through 2028. About Xencor Xencor is a clinical-stage biopharmaceutical company developing engineered antibodies for the treatment of patients with cancer and autoimmune diseases. More than 20 candidates engineered with Xencor's XmAb® technology are in clinical development, and multiple XmAb medicines are marketed by partners. Xencor's XmAb engineering technology enables small changes to a protein’s structure that result in new mechanisms of therapeutic action. For more information, please visit . Fiscal Year 2025 Preliminary Financial Results The financial information included herein for the fiscal year ended December 31, 2025, including the estimate of Xencor’s cash, cash equivalents, and marketable debt securities as of December 31, 2025, is preliminary, unaudited and subject to completion, including the completion of year-end closing procedures as of and for the year ended December 31, 2025. As a result, the unaudited preliminary balance set forth above reflects Xencor’s preliminary estimate with respect to such information, based on information currently available to management, and may vary from Xencor’s actual financial position as of December 31, 2025. Forward-Looking Statements Certain statements contained in this press release may constitute forward-looking statements within the meaning of the “safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include statements that are not purely statements of historical fact, and can generally be identified by the use of words such as “potential,” “can,” “will,” “plan,” “may,” “could,” “would,” “expect,” “anticipate,” “seek,” “look forward,” “believe,” “committed,” “investigational,” “indicates,” “supports,” and similar terms, or by express or implied discussions relating to Xencor’s business, including, but not limited to, statements regarding our expectations regarding regulatory and partnership milestone achievements, clinical pipeline advancements and our ability to fund our research and development programs through 2028, the quotations from Xencor's president and chief executive officer, and other statements that are not purely statements of historical fact. Such statements are made on the basis of the current beliefs, expectations, and assumptions of the management of Xencor and are subject to significant known and unknown risks, uncertainties and other factors that may cause actual results, performance or achievements and the timing of events to be materially different from those implied by such statements, and therefore these statements should not be read as guarantees of future performance or results. Such risks include, without limitation, the risks associated with the process of discovering, developing, manufacturing and commercializing drugs that are safe and effective for use as human therapeutics, the ability of publicly disclosed preliminary clinical trial data to support continued clinical development and regulatory approval for specific treatments, the risk of loss of key members of management, the risk that the fair value of our marketable equity securities will decline and the risks, uncertainties and other factors described under the heading “Risk Factors” in Xencor's annual report on Form 10-K for the year ended December 31, 2024 as well as Xencor's subsequent filings with the Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. Xencor undertakes no obligation to revise or update these forward-looking statements to reflect events or circumstances after the date hereof, except as required by law. Contacts Charles Liles cliles@xencor.com (626) 737-8118 For media: Cassidy McClain Inizio Evoke cassidy.mcclain@inizioevoke.com (619) 694-6291