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Phillips, Tycel

https://orcid.org/0000-0003-2143-9672

Mayo Clinic

City Of Hope National Medical Center

Citations 30

Updated follow‐up of BELLWAVE‐001: an open‐label, single‐arm, phase 1/2 study of the efficacy and safety of nemtabrutinib for the treatment of B‐cell malignancies
Eradat, Herbert, Woyach, Jennifer A. , Brander, Danielle M. , Tees, Michael, Ghori, Razi , Farooqui, Mohammed Z.H. , Byrd, John C. , Flinn, Ian W. , Awan, Farrukh T. , Parikh, Sameer A. , Phillips, Tycel , Paydar, Ima , Stephens, Deborah M.

Hematological Oncology | June 9, 2023 | Volume: 41 | Issue: S2 | Pages: 565-567

10.1002/hon.3164_423 Get It

Blockade of CCR1 induces a phenotypic shift in macrophages and triggers a favorable antilymphoma activity
Le, Kang , Sun, Jing , Ghaemmaghami, Javid, Ip, W. K. Eddie, Phillips, Tycel , Gupta, Mamta , Phillips, Tycel , Gupta, Mamta , Ghaemmaghami, Javid , Smith, Mitchell R.

Blood Advances | January 11, 2023 | Volume: 7 | Issue: 15 | Pages: 3952-3967

10.1182/bloodadvances.2022008722 Get It

Abstract Tumor-associated macrophages (TAMs) within the tumor microenvironment (TME) play an important role in tumor growth and progression. TAMs have been involved in producing immunosuppressive TME via various factors; however, the underlying mechanisms remain unclear in B-cell lymphoma, including mantle cell lymphoma (MCL). We identified that chemokine receptor-1 (CCR1) is highly expressed on monocytes (Mo) and macrophages (MΦ), and CCR1 pharmacological inhibition or CCR1 siRNA abolished lymphoma-mediated Mo/MΦ migration in a chemotaxis assay. The deficiency of host CCR1 (CCR1 KO) was associated with decreased infiltration of peritoneal-MΦ compared with WT-CCR1. Functional studies indicated that the genetic depletion of CCR1 or treatment inhibited protumor MΦ (M2-like) phenotype by decreasing CD206 and IL-10 expression. Moreover, CCR1 depletion reprogrammed MΦ toward an MHCII+/TNFα+ immunogenic phenotype. Mechanistically, protumor MΦ driven–IL-10 provides a positive feedback loop to tumor-CCL3 by regulating the CCL3 promoter via STAT1 signaling. Therapeutic in vivo targeting of CCR1 with CCR1 antagonist BX-471 significantly reduced FC-muMCL1 mouse tumors in the syngeneic MCL model by the depletion of M2-TAMs and increased infiltration of cytotoxic CD8+ T cells. Our study established that CCR1 exerts a pivotal role in macrophage programming, thus shaping protumor TME and lymphoma progression. CCR1 inhibition through CCR1 antagonists may be a promising therapeutic strategy to reprogram macrophages in lymphoma-TME and achieve better clinical outcomes in patients.
A Multi-Center Study: Outcomes Among Relapsed/Refractory Diffuse Large B Cell Lymphoma Patients with CD20 Loss
Takiar, Radhika , Ng, Wern Lynn , Shah, Eshana, Boonstra, Philip S. , Karimi, Yasmin , Zamalloa, Carlos A. Murga, Nowakowski, Grzegorz S. , Karimi, Yasmin H , Carty, Shannon A. , Wilcox, Ryan A. , Phillips, Tycel

Blood | November 29, 2022 | Volume: 140 | Issue: Supplement 1 | Pages: 9510-9511

10.1182/blood-2022-158825 Get It

A Phase 1 Study of Plamotamab, an Anti-CD20 x Anti-CD3 Bispecific Antibody, in Patients with Relapsed/Refractory Non-Hodgkin's Lymphoma: Recommended Dose Safety/Efficacy Update and Escalation Exposure-Response Analysis
Patel, Krish , Tilly, Hervé , Ghesquières, Hervé , Collela, Jean Marc Schiano de, Chanan‐Khan, Asher , Bouabdallah, Kamal , Long, Meixiao, Clynes, Raphael , Kanodia, Jitendra , Bao, Lei , Ding, Ying , Jin, Jianhua , Ainsworth, William B., Garcha, Raman, Kye, Steve, Patel, Krish , Riedell, Peter A. , Ahmed, Sairah , Michot, Jean‐Marie , Tessoulin, Benoit , Iyengar, Sunil , Bao, Lei, Phillips, Tycel

Blood | November 28, 2022 | Volume: 140 | Issue: Supplement 1 | Pages: 9470-9472

10.1182/blood-2022-159586 Get It

Efficacy and Safety of Nemtabrutinib, a Wild-Type and C481S-Mutated Bruton Tyrosine Kinase Inhibitor for B-Cell Malignancies: Updated Analysis of the Open-Label Phase 1/2 Dose-Expansion Bellwave-001 Study
Woyach, Jennifer A. , Eradat, Herbert, Brander, Danielle M. , Tees, Michael, Ghori, Razi , Reddy, Nishitha , Farooqui, Mohammed Z.H. , Byrd, John C. , Byrd, John C , Flinn, Ian W. , Awan, Farrukh T. , Parikh, Sameer A. , Phillips, Tycel , Stephens, Deborah M.

Blood | November 28, 2022 | Volume: 140 | Issue: Supplement 1 | Pages: 7004-7006

10.1182/blood-2022-163596 Get It

Closing the Gap: Implementation of a Novel Interactive Virtual Tumor Board to Improve Expert Knowledge Sharing in Malignant Hematology
Ciuro, Jordan , Henry, Elizabeth , Housri, Nadine , Brém, Elizabeth , Brooks, Taylor , Derman, Ben A, Hill, Brian T. , Lunning, Matthew A. , Rutherford, Sarah C. , Zanwar, Saurabh , Lee, Lauren E. , Brooks, Taylor R , Banerjee, Rahul , Hofmeister, Craig C. , Matasar, Matthew J. , Phillips, Tycel

Blood | November 28, 2022 | Volume: 140 | Issue: Supplement 1 | Pages: 13180-13181

10.1182/blood-2022-167959 Get It

P682: NEMTABRUTINIB (MK-1026), A NON-COVALENT INHIBITOR OF WILD-TYPE AND C481S MUTATED BRUTON TYROSINE KINASE FOR B-CELL MALIGNANCIES: EFFICACY AND SAFETY OF THE PHASE 2 DOSE-EXPANSION BELLWAVE-001 STUDY
Woyach, Jennifer A. , Eradat, Herbert, Brander, Danielle M. , Tees, Michael, Wang, W., Reddy, Nishitha , Farooqui, Mohammed, Flinn, Ian W. , Awan, Farrukh T. , Parikh, Sameer A. , Phillips, Tycel , Byrd, John C. , Stephens, Deborah M.

HemaSphere | June 23, 2022 | Volume: 6 | Issue: No issue available | Pages: 578-579

10.1097/01.hs9.0000845612.25766.0c Get It

Zanubrutinib monotherapy in relapsed/refractory indolent non-Hodgkin lymphoma
Chan, Henry , Tam, Constantine S. , Tedeschi, Alessandra , Johnston, Patrick B. , Opat, Stephen , Eom, Hyeon‐Seok , Allewelt, Heather, Tan, Ziwen , Novotny, William , Huang, Jane , Chan, Henry , Tam, Constantine S , Opat, Stephen , Eom, Hyeon-Seok , Trotman, Judith , Phillips, Tycel , Oh, Sung Yong , Stern, Jennifer C.

Blood Advances | April 7, 2022 | Volume: 6 | Issue: 11 | Pages: 3472-3479

10.1182/bloodadvances.2021006083 Get It

Abstract Outcomes for marginal zone lymphoma (MZL) and follicular lymphoma (FL) remain suboptimal, owing to the limited number of approved agents and the incurable nature of the diseases. BGB-3111-AU-003 was a phase 1/2, open-label, multicenter, single-agent study of the selective Bruton’s tyrosine kinase inhibitor zanubrutinib in 385 patients with B-cell malignancies. Here, we present safety and efficacy outcomes for the 53 enrolled patients with relapsed/refractory MZL (n = 20) and relapsed/refractory FL (n = 33), all of whom were enrolled during the part 2 dose expansion, and therefore received zanubrutinib at the recommended phase 2 dose. Treatment with zanubrutinib was generally well tolerated, with most adverse events being ≤ grade 2. Atrial fibrillation/flutter was not reported. Two patients required dose reduction, and 4 patients discontinued treatment because of adverse events. Response was assessed by an independent review committee for MZL and the investigators for FL, per Lugano 2014 classification for non-Hodgkin lymphoma. In patients with MZL, the overall response rate (ORR) was 80%, and the complete response (CR) rate was 20%. With median follow-up of 33.8 months, median progression-free survival (PFS) was not reached. In patients with FL, the ORR was 36.4%, and the CR rate was 18.2%. After a median follow-up of 33.9 months, median PFS was 10.4 months. In conclusion, the results of this study suggest a favorable benefit–risk profile and support zanubrutinib as a potentially meaningful addition to available therapies for patients with relapsed/refractory MZL and FL. This trial was registered at www.clinicaltrials.gov as #NCT02343120.
Preliminary Efficacy and Safety of MK-1026, a Non-Covalent Inhibitor of Wild-Type and C481S Mutated Bruton Tyrosine Kinase, in B-Cell Malignancies: A Phase 2 Dose Expansion Study
Woyach, Jennifer A. , Eradat, Herbert, Brander, Danielle M. , Tees, Michael, Wang, Wayne , Reddy, Nishitha , Farooqui, Mohammed Z.H. , Byrd, John C. , Byrd, John C. , Flinn, Ian W. , Awan, Farrukh T. , Parikh, Sameer A. , Phillips, Tycel , Stephens, Deborah M. , Byrd, John C

Blood | November 24, 2021 | Volume: 138 | Issue: Supplement 1 | Pages: 392-392

10.1182/blood-2021-148672 Get It

Abstract Introduction: Bruton tyrosine kinase inhibitors (BTKi) have revolutionized the treatment of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and certain B-cell neoplasms. However, resistance to BTKi develops primarily through mutations at the cysteine binding site (C481) or PLCγ2 mutations. MK-1026 (formerly ARQ-531) is a non-covalent, potent inhibitor of both wild type and C481- mutated BTK. In the phase 1/2 dose escalation and dose expansion study NCT03162536, the preliminary recommended phase 2 dose (RP2D) of MK-1026 was determined to be 65 mg once daily. The efficacy and safety of MK-1026 in participants with CLL/SLL and B-cell non-Hodgkin lymphoma (NHL) were also evaluated at a higher dose during the dose expansion phase. Methods: In this open-label, single-arm phase 2 study, 9 expansion cohorts were initiated following determination of preliminary MK-1026 RP2D. Approximately 10-25 eligible participants were enrolled into Cohort A (relapsed/refractory (r/r) CLL/SLL, with ≥2 prior therapies including covalent BTKi, with documented C481 mutation), Cohort B (r/r CLL/SLL progressed on/intolerant to a BTKi, with ≥2 prior therapies without C481 mutation), Cohort C (participants with Richter transformation [RT] with ≥1 prior therapy), Cohort D-H (participants with follicular lymphoma (FL), mantle cell lymphoma (MCL), marginal zone lymphoma (MZL), high-grade B cell lymphoma (BCL) with known MYC, BCL-2 or BCL-6 translocations, and Waldenström macroglobulinemia (WM), respectively, who received ≥2 prior therapies), Cohort I (food effect cohort including participants with B-cell NHL, CLL/SLL, and WM). Treatment continued until unacceptable toxicity, clinical or radiological progression, participant/physician withdrawal. Primary endpoint was overall response rate (per iwCLL criteria, by investigator) for participants with CLL/SLL. Secondary endpoints included duration of response and safety and tolerability. The data cut-off date for this analysis was April 7, 2021. Results: Among 118 participants enrolled, 44 had B-cell NHL (including 6 with DLBCL, 11 with FL, 3 with high-grade BCL, 6 with MCL, 2 with MZL, 16 with RT), 68 CLL/SLL, and 4 WM. Of these, 94 (79.6%) were treated at the preliminary RP2D, including 51 (54.3%) participants with CLL/SLL. Participants with CLL/SLL had a median (range) number of prior therapies of 4 (1-18), 43 (84%) had prior BTKi therapy, 12 (23%) had del17p, 26 (51%) had IGHV unmutated status, and 32 (63%) had C481S BTK mutation. At data cut-off, median (range) follow-up was 4.56 months (0.1-26.7) for all treated participants. ORR was 57.9% (N = 22 of 38; 1 CR, 21 PR/PRL) per iwCLL criteria in the efficacy evaluable population of participants with CLL/SLL treated at preliminary RP2D. The median duration of response in these participants was not estimable [NE] (range, 8.3 months-NE). At data cut-off, the median duration of treatment exposure was 3.2 months (range, 0-35.9). Among all treated participants, 114 (97%) had a treatment-emergent adverse event (TEAE), with 78 (66%) having a drug-related TEAE, and 9 (8%) having a drug-related TEAE that led to discontinuation. Common TEAEs (≥ 20%) included fatigue (33%), constipation (31%), dysgeusia (28%), cough (25%), nausea (25%), pyrexia (25%), dizziness (23%), hypertension (23%), peripheral edema (22%), arthralgia (20%), and diarrhea (21%). Grade ≥3 TEAEs occurred in 80 (68%) participants. Grade 5 TEAEs occurred in 7 (6%) participants and included death following disease progression in 3 (3%), sepsis 1 (1%), dyspnea 1 (1%), and respiratory failure 2 (2%) participants. Common drug-related TEAEs (≥10%) included dysgeusia (15%), nausea (11%), fatigue (11%), and decreased neutrophil count (10%). Grade 3-4 drug-related TEAEs occurred in 31 (26%) participants. No drug-related TEAEs led to death. Conclusion: MK-1026 has promising antitumor activity with a manageable safety profile in participants with CLL/SLL exposed to multiple lines of therapy, including in those who had progression of disease on prior covalent BTKi. Further evaluation of MK-1026 in B-cell malignancies is ongoing. Disclosures Woyach: AbbVie Inc, ArQule Inc, Janssen Biotech Inc, AstraZeneca, Beigene: Other: Advisory Committee; AbbVie Inc, ArQule Inc, AstraZeneca Pharmaceuticals LP, Janssen Biotech Inc, Pharmacyclics LLC, an AbbVie Company,: Consultancy; AbbVie Inc, Loxo Oncology Inc, a wholly owned subsidiary of Eli Lilly & Company: Research Funding; Gilead Sciences Inc: Other: Data & Safety. Flinn: Verastem: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Genentech: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; IGM Biosciences: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Gilead Sciences: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Juno Therapeutics: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Yingli Pharmaceuticals: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Constellation Pharmaceuticals: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Loxo: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Kite, a Gilead Company: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Novartis: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; AbbVie: Consultancy, Other: All Consultancy and Research Funding payments made to Sarah Cannon Research Institute, Research Funding; AstraZeneca: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Great Point Partners: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Iksuda Therapeutics: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; BeiGene: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Forty Seven: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Calithera Biosciences: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Roche: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Unum Therapeutics: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; MorphoSys: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Merck: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; TG Therapeutics: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Janssen: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Teva: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Takeda: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Seagen: Consultancy, Other: All consultancy and research funding payments made to Sarah Cannon Research Institute, Research Funding; Karyopharm Therapeutics: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Celgene: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Incyte: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Infinity Pharmaceuticals: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Agios: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Curis: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Acerta Pharma: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; ArQule: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Pfizer: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Forma Therapeutics: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Nurix Therapeutics: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Portola Pharmaceuticals: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Rhizen Pharmaceuticals: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Trillium Therapeutics: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Triphase Research & Development Corp.: Other: All research funding payments made to Sarah Cannon Research Institute, Research Funding; Century Therapeutics: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Hutchison MediPharma: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Vincerx Pharma: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Sarah Cannon Research Institute: Current Employment; Servier Pharmaceuticals: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Yingli Pharmaceuticals: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Seagen: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Servier Pharmaceuticals: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute; Unum Therapeutics: Consultancy, Other: All consultancy payments made to Sarah Cannon Research Institute, Research Funding; Johnson & Johnson: Current holder of individual stocks in a privately-held company; Seattle Genetics: Research Funding. Awan: Verastem: Consultancy; Incyte: Consultancy; Dava Oncology: Consultancy; MEI Pharma: Consultancy; Beigene: Consultancy; Celgene: Consultancy; Johnson and Johnson: Consultancy; Karyopharm: Consultancy; Kite pharma: Consultancy; Gilead sciences: Consultancy; Pharmacyclics: Consultancy; Janssen: Consultancy; BMS: Consultancy; Merck: Consultancy; Cardinal Health: Consultancy; ADCT therapeutics: Consultancy; Abbvie: Consultancy; Astrazeneca: Consultancy; Genentech: Consultancy. Eradat: AstraZeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Beigene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Incyte: Speakers Bureau; Juno: Research Funding; Kite: Research Funding; Genentech: Research Funding. Brander: Pfizer: Consultancy, Other: Biosimilars outcomes research panel; Juno Therapeutics/Celgene/Bristol Myers Squibb: Research Funding; ArQule: Research Funding; Ascentage: Research Funding; AstraZeneca: Research Funding; BeiGene: Research Funding; DTRM: Research Funding; Pharmacyclics LLC, an AbbVie Company: Consultancy, Research Funding; MEI Pharma: Research Funding; TG Therapeutics: Consultancy, Research Funding; Novartis: Research Funding; LOXO: Research Funding; Verastem: Consultancy; ArQule/Merck: Consultancy; Genentech: Consultancy, Research Funding; NCCN: Other: panel member; AbbVie: Consultancy, Other: informCLL registry steering committee, Research Funding. Parikh: Pharmacyclics, MorphoSys, Janssen, AstraZeneca, TG Therapeutics, Bristol Myers Squibb, Merck, AbbVie, and Ascentage Pharma: Research Funding; Pharmacyclics, AstraZeneca, Genentech, Gilead, GlaxoSmithKline, Verastem Oncology, and AbbVie: Membership on an entity's Board of Directors or advisory committees. Phillips: BMS: Consultancy, Research Funding; AstraZeneca: Consultancy; Incyte: Consultancy, Other: received travel expenses from Incyte, Research Funding; Genentech: Membership on an entity's Board of Directors or advisory committees, Research Funding; AbbVie: Consultancy, Research Funding; ADCT, BeiGene, Bristol Myers Squibb, Cardinal Health, Incyte, Karyopharm, Morphosys, Pharmacyclics, Seattle Genetics: Consultancy; Bayer: Consultancy, Research Funding. Reddy: Merck & Co., Inc.: Current Employment. Farooqui: Merck & Co., Inc.: Current Employment, Other: Current Stockholder. Byrd: Vincerx Pharmaceuticals: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Novartis, Trillium, Astellas, AstraZeneca, Pharmacyclics, Syndax: Consultancy, Honoraria; Newave: Membership on an entity's Board of Directors or advisory committees. Stephens: CSL Behring: Consultancy; Innate Pharma: Membership on an entity's Board of Directors or advisory committees; Beigene: Membership on an entity's Board of Directors or advisory committees; Epizyme: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Adaptive: Membership on an entity's Board of Directors or advisory committees; Arqule: Research Funding; Mingsight: Research Funding; JUNO: Research Funding; Novartis: Research Funding; Abbvie: Consultancy; AstraZeneca: Consultancy; Celgene: Consultancy; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Research Funding.
Safety and Anti-Tumor Activity of Plamotamab (XmAb13676), an Anti-CD20 x Anti-CD3 Bispecific Antibody, in Subjects with Relapsed/Refractory Non-Hodgkin's Lymphoma
Patel, Krish , Chanan‐Khan, Asher , Ghesquières, Hervé , Bouabdallah, Kamal , Byrd, John C. , Portell, Craig A. , Solh, Melhem , Tilly, Hervé , McGovern, Patricia, Johnson, Chelsea, Garcha, Raman, Brisou, Gabriel , Liebowitz, David, Patel, Krish , Portell, Craig A , Michot, Jean‐Marie , Cartron, Guillaume , Wierda, William G. , Ribrag, Vincent , Phillips, Tycel , Byrd, John C

Blood | November 24, 2021 | Volume: 138 | Issue: Supplement 1 | Pages: 2494-2494

10.1182/blood-2021-144350 Get It

Abstract Introduction: Plamotamab (XmAb13676) is a humanized bispecific antibody that binds both CD20 and CD3 to recruit cytotoxic T cells to kill CD20 expressing malignant cells. Interim results of an ongoing first-in-human (FIH), dose-escalation study (XmAb13676-01; NCT02924402) in subjects with relapsed/refractory (R/R) non-Hodgkin's lymphoma (NHL) are reported. Methods: The study is an FIH, multi-center, open-label, phase 1, dose-escalation study in subjects with R/R NHL with a standard 3 + 3 design. The primary objectives are to determine safety, tolerability, and the maximum tolerated dose (MTD) or recommended dose of plamotamab. Secondary objectives include preliminary anti-tumor activity and pharmacokinetics/pharmacodynamics of plamotamab. This study has 3 Parts: Part A, escalating dose cohorts that establish an initial priming dose as part of repeated weekly infusions at a fixed, weight-based dose in a 28-day cycle; Part B, with a dosing schedule consisting of a priming dose on Cycle 1 Day 1, established in Part A, followed by step-up dosing (SUD) on subsequent weeks; and Part C is an SUD regimen with flat and less frequent dosing. Cytokine release syndrome (CRS) prophylaxis with dexamethasone, antihistamine, and acetaminophen was mandated prior to each administration of plamotamab. Treatment was continued for 2 cycles or longer if there was evidence of therapeutic benefit. Results: At data cut-off (01Jul2021), 80 subjects with NHL have been treated. Subjects had a median age of 62 years (range 32-89), a median of 4 prior therapies (range 1-10), and had been diagnosed a median of 28 months (range 6-353) prior to treatment in the study. The most common treatment-related adverse event was CRS. Overall, 50 subjects (62.5%) experienced CRS, with 4 (5.0%) experiencing Grade ≥ 3 CRS. No related neurotoxicity >Grade 2 has been observed. Treatment responses for NHL were assessed by the Lugano criteria or International Working Group criteria for Waldenström Macroglobulinemia. There have been 23 objective responses (43.4% overall response rate [ORR]) and 13 (38.2%) at doses of ≥ 80 µg/kg or flat dosing in all evaluable subjects with NHL and diffuse large cell B-cell lymphoma, respectively. In the efficacy-evaluable, follicular lymphoma population, at doses of 80-360 µg/kg or flat dosing, objective responses were observed in 8/10 (80%) subjects. After implementation of flat dosing, as opposed to weight-based dosing, a 50% ORR (4/8 evaluable subjects) has been observed in NHL subjects in that cohort. An MTD has not been reached, and dose escalation is ongoing. Overall, 4 out of 16 (25%) evaluable subjects with prior CAR-T therapy responded to plamotamab. Conclusions: Plamotamab demonstrated evidence of clinical activity in heavily pretreated subjects with R/R NHL. CRS was generally manageable with premedication. The study is ongoing with further optimization of dose and schedule. Figure 1 Figure 1. Disclosures Patel: Kite Pharma: Consultancy, Speakers Bureau; Genentech: Consultancy; Morphosys: Consultancy; Bristol Myers Squibb: Consultancy, Speakers Bureau; BeiGene: Consultancy; Janssen: Consultancy; AstraZeneca: Consultancy, Research Funding, Speakers Bureau; Pharmacyclics: Consultancy; Abbvie: Consultancy; TG Therapeutics: Consultancy, Speakers Bureau; MEI Pharma: Consultancy; ADC Therapeutics: Consultancy; Lilly: Consultancy. Michot: GSK: Honoraria; Celgene: Honoraria; MSD: Consultancy, Honoraria; Innate Pharma: Research Funding; Incyte: Research Funding; H3 biomedecine: Research Funding; GSK: Consultancy, Honoraria, Research Funding; Genentech: Research Funding; Gamamabs: Research Funding; Forma: Research Funding; Exelixis: Research Funding; Eos: Research Funding; Eisai: Research Funding; Debiopharm: Research Funding; Daiichi Sankyo,: Research Funding; Clovis: Research Funding; Chugai: Research Funding; Boeringer Ingelheim: Research Funding; Celgene: Research Funding; Blueprint: Research Funding; Beigene: Research Funding; Bayer: Research Funding; Argen-x: Research Funding; Amgen: Research Funding; Agios: Research Funding; Aduro: Research Funding; Abbvie: Research Funding; ASTEX: Research Funding, Speakers Bureau; Astra Zeneca: Honoraria, Research Funding; Roche: Honoraria; Bristol Myers Squibb: Consultancy, Honoraria, Research Funding. Chanan-Khan: Alpha2 Pharmaceuticals, NonoDev, Starton: Current holder of stock options in a privately-held company; Ascentage: Research Funding; Cellectar: Current equity holder in publicly-traded company; Alpha2 Pharmaceuticals: Patents & Royalties: Tabi; Ascentage, Starton, Cellectar, NonoDev, Alpha2 Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; BeiGene, Jansen, Ascentage: Honoraria; BieGene, Jansen, Ascentage: Consultancy. Ghesquieres: Janssen: Honoraria; Mundipharma: Consultancy, Honoraria; Roche: Consultancy; Celgene: Consultancy, Honoraria; Gilead Science: Consultancy, Honoraria. Byrd: Vincerx Pharmaceuticals: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Novartis, Trillium, Astellas, AstraZeneca, Pharmacyclics, Syndax: Consultancy, Honoraria; Newave: Membership on an entity's Board of Directors or advisory committees. Cartron: Roche, Celgene-BMS: Consultancy; Danofi, Gilead, Novartis, Jansen, Roche, Celgene-BMS, Abbvie, Takeda: Honoraria. Portell: Acerta/AstraZeneca: Research Funding; Xencor: Research Funding; SeaGen: Research Funding; Targeted Oncology: Honoraria; Aptitude Health: Honoraria; Abbvie: Research Funding; Pharmacyclics: Honoraria; Kite: Honoraria, Research Funding; Merck: Honoraria, Research Funding; BeiGene: Honoraria, Research Funding; Morphosys: Honoraria; TG Therapeutics: Honoraria, Research Funding; Genentech: Research Funding; VelosBio: Research Funding. Solh: Jazz Pharmaceuticals: Consultancy; Partner Therapeutics: Research Funding; BMS: Consultancy; ADCT Therapeutics: Consultancy, Research Funding. Wierda: Loxo Oncology, Inc.: Research Funding; GSK/Novartis: Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; Miragen: Research Funding; Sunesis: Research Funding; Gilead Sciences: Research Funding; KITE Pharma: Research Funding; Genentech: Research Funding; Janssen: Research Funding; Juno Therapeutics: Research Funding; Acerta Pharma Inc.: Research Funding; Xencor: Research Funding; AstraZeneca: Research Funding; Cyclacel: Research Funding; Oncternal Therapeutics, Inc.: Research Funding; Karyopharm: Research Funding; Genzyme Corporation: Consultancy; AbbVie: Research Funding. Johnson: Xencor: Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months, Ended employment in the past 24 months. Garcha: Xencor: Current Employment, Current equity holder in publicly-traded company, Current holder of stock options in a privately-held company; Promedim: Ended employment in the past 24 months. Ribrag: AstraZeneca: Membership on an entity's Board of Directors or advisory committees; GSK: Research Funding; MSD Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; Infinity Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Servier: Consultancy, Membership on an entity's Board of Directors or advisory committees; Argen-X: Research Funding; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Astex Pharmaceuticals: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees; Nanostring: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; PharmaMar: Honoraria, Membership on an entity's Board of Directors or advisory committees; Epizyme: Honoraria, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees. Liebowitz: Xencor: Current Employment, Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months. Phillips: Incyte: Consultancy, Other: received travel expenses from Incyte, Research Funding; ADCT, BeiGene, Bristol Myers Squibb, Cardinal Health, Incyte, Karyopharm, Morphosys, Pharmacyclics, Seattle Genetics: Consultancy; AbbVie: Consultancy, Research Funding; AstraZeneca: Consultancy; BMS: Consultancy, Research Funding; Genentech: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Consultancy, Research Funding.