On December 6, 2025 Aptose Biosciences Inc. ("Aptose" or the "Company") (NASDAQ: APTO, TSX: APS), a clinical-stage precision oncology company developing highly differentiated targeted agents to treat hematologic malignancies, reported clinical data for its lead compound tuspetinib (TUS) combined with standard dosing of venetoclax (VEN) and azacitidine (AZA) in a poster presentation at the 67th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting in Orlando, FL. Updated data from patients in the TUSCANY trial across all three cohorts, 40 mg, 80 mg or 120 mg TUS dose in TUS+VEN+AZA, reveal promising clinical safety and antileukemic activity and support the use of TUS in combination with standard of care treatment across a broad range of AML populations, including those with adverse mutations regardless of FLT3 mutation status.

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Poster title: "TUSCANY study demonstrates safety and efficacy of tuspetinib plus standard of care venetoclax and azacitidine in patients with newly diagnosed AML ineligible for induction chemotherapy"

Key Findings and Messages:

In newly diagnosed AML patients, TUS+VEN+AZA shows promising safety, tolerability and resilient efficacy, including MRD-negative remissions across a broad mutational spectrum
High-quality clinical responses (CR/CRh):
90% across 40, 80 and 120 mg dose levels
100% at the higher 80 mg and 120 mg dose levels
Observed in FLT3-WT, FLT3-ITD, and NPM1c genetic subgroups
Observed in biallelic TP53/complex karyotype and RAS adverse genetic subgroups
Observed in AML with MDS-related mutations
MRD negativity: 78% by central flow cytometry in responding subjects
TUS targets VEN resistance mechanisms; inhibits kinase-driven abnormal signaling
Two subjects transitioned to stem cell transplantation and both returned for TUS maintenance
TUS+VEN+AZA triplet therapy was well tolerated with no dose-limiting toxicities (DLTs) across all evaluable TUS dose levels
No DLTs including no prolonged myelosuppression for subjects in remission in Cycle 1
No drug-related deaths, differentiation syndrome, QTc prolongation, or CPK elevation reported
8/10 evaluable subjects experienced red cell and platelet transfusion independence for > 8 weeks after their best response
Febrile neutropenia was reported in 2 subjects (16.7%), with 1 subject related to TUS
At the recently enrolled 160 mg dose level, preliminary findings show patients achieving early blast clearance with MRD-negativity and formal responses in the first few weeks of treatment (not included in poster data cut).

"Tuspetinib, as part of a triple drug therapy, continues to perform well, achieving 100% clinical response in the two higher doses we have evaluated to date," said Rafael Bejar, MD, PhD, Chief Medical Officer at Aptose. "We recently commenced treating patients at the highest dose level of 160 mg TUS and have already achieved early responses. With no dose-limiting toxicities and activity across diverse mutations, TUS+VEN+AZA targets AML’s greatest unmet needs and largest populations."

The ASH (Free ASH Whitepaper) poster presentation is available here.

About Tuspetinib

Aptose’s lead compound tuspetinib is a convenient once daily oral agent that potently targets SYK, mutated and wild type forms of FLT3, mutated KIT, JAK1/2, and RSK2 kinases, while avoiding many typical toxicity concerns observed with other agents. The ongoing TUSCANY triplet Phase 1/2 study is designed to test various doses and schedules of TUS in combination with standard dosing of azacitidine and venetoclax in newly diagnosed patients with AML who are ineligible to receive induction chemotherapy. Data from the first three dose cohorts demonstrate safety, CRs and minimal residual disease (MRD) negativity across patients with diverse mutations. The early data showed that 9 out of 10 patients responded to the TUS triplet therapy, with 100% complete remission (CR/CRh) achieved in the 80mg and 120mg cohorts. Notably, patients with difficult-to-treat mutations in TP53, RAS and FLT3 genes also achieved a 100% CR/CRh rate.

(Press release, Aptose Biosciences, DEC 6, 2025, View Source [SID1234661210])

On December 6, 2025 Protagonist Therapeutics, Inc. ("Protagonist") (NASDAQ:PTGX) and Takeda (TSE:4502/NYSE:TAK) reported that new 52-week results from the pivotal Phase 3 VERIFY study evaluating rusfertide in patients with polycythemia vera (PV) will be presented in an oral presentation at the 67th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting and Exposition. These findings further reinforce rusfertide’s efficacy and safety and demonstrate durability of response, with 61.9% of patients continuously treated with rusfertide maintaining absence of phlebotomy eligibility from baseline to Week 52.

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"The 52-week data demonstrated the sustained efficacy of rusfertide, reducing the need for patients to receive phlebotomy while maintaining hematocrit control," said Dr. Andrew T. Kuykendall, M.D., VERIFY Lead Investigator and Associate Member in the Department of Hematology at Moffitt Cancer Center. "The 32-week VERIFY primary results were already promising, and this deeper understanding of the durability of response with rusfertide is critical to inform clinical decision-making for polycythemia vera. In totality, these findings, including the long-term extension data from THRIVE, reaffirm rusfertide as a potential new addition to the standard of care for patients with PV."

Achieving and maintaining controlled hematocrit (HCT) levels of <45% is the primary treatment goal in PV to prevent thrombotic events and help alleviate symptoms. However, many patients still experience uncontrolled hematocrit levels and burdensome symptoms with current standard of care treatments. The VERIFY study, designed to evaluate the efficacy and safety of rusfertide in patients with uncontrolled hematocrit who are phlebotomy-dependent despite receiving current standard of care treatment, met the primary endpoint and all four key secondary endpoints in its previously-reported 32-week primary analysis. During Part 1a (Weeks 0-32) of the VERIFY study, 293 patients were randomized to receive either rusfertide (147 patients) or placebo (146 patients), as an add-on to their current treatment. During Part 1b (Weeks 32-52), all participants were eligible to receive open-label rusfertide to evaluate the durability of the treatment response. 274 patients (94%) continued into Part 1b, and 267 patients (91%) remained in the study through Week 52, with 254 continuing to receive rusfertide in Part 2 (Weeks 52-156).

Key findings at 52 Weeks include1,2:

Phlebotomy Eligibility

61.9% of patients treated with rusfertide plus current standard of care throughout Parts 1a and 1b of the study experienced a durable clinical response, defined as absence of phlebotomy eligibility.
84.1% of patients treated with rusfertide who experienced a clinical response in the Part 1a assessment window (Weeks 20-32) maintained their response.
77.9% of patients who crossed over from placebo to rusfertide at Week 32 for Part 1b experienced a clinical response during the Part 1b assessment window (Weeks 40-52).
Median time to first phlebotomy was 16 Weeks in the placebo group, while median time to first phlebotomy was not reached in either the rusfertide group in Part 1a or 1b, or the placebo to rusfertide crossover group in Part 1b.
HCT Control

Mean hematocrit remained <43% through Week 52 in patients treated with rusfertide throughout Part 1a and Part 1b and those who switched from placebo to rusfertide for Part 1b.
Median time to first hematocrit ≥ 45% was 8.3 Weeks in the placebo group in Part 1a, while median time to first hematocrit ≥ 45% was not reached in the rusfertide group during Parts 1a or 1b.
Quality of Life Endpoints

Patients treated with rusfertide in Parts 1a and 1b maintained improvements in patient reported outcomes as measured by PROMIS Fatigue SF-8a and MFSAF TSS7.
Rusfertide was generally well-tolerated through 52 Weeks of treatment. The most common treatment-emergent adverse events (AE) in rusfertide-treated patients were injection site reactions (47.4%), anemia (25.6%) and fatigue (19.6%), which were primarily grade 1 or 2. Serious AEs occurred in 8.1% of overall rusfertide-treated patients.

The durability of response and safety profile of rusfertide in patients with PV from the 52-week VERIFY data are further supported by the four-year analysis of 46 patients who continued from REVIVE to the long-term extension study, THRIVE.

The results show that after transitioning to THRIVE, continued treatment with rusfertide with or without cytoreductive therapy demonstrated consistent, long-term hematocrit control with a greater than 13-fold reduction in estimated annual therapeutic phlebotomy rate compared to baseline prior to study entry in REVIVE. Prior to study entry in REVIVE, the mean annualized phlebotomy rate (i.e., phlebotomy/year) for the 46 patients who eventually rolled over to THRIVE was 9.2 phlebotomies/year. The mean annualized phlebotomy rate during THRIVE was 0.7 phlebotomies/year.3 Rusfertide’s safety profile was consistent with prior observations.

"The totality of these data further demonstrates rusfertide’s well tolerated safety profile and ability to deliver durable hematocrit control and clinical response as defined by absence of phlebotomy eligibility and support its potential to expand the treatment armamentarium for PV and positively impact the lives of patients with PV," said Arturo Molina, M.D., M.S., Chief Medical Officer at Protagonist. "We look forward to continuing to work with our partner, Takeda, to prepare for submission of an NDA to the FDA."

"We are committed to making a difference for patients with PV who face serious risks from thrombotic events if they are unable to adequately control hematocrit levels with currently available treatment options," said Phuong Khanh (P.K.) Morrow, M.D., Head of the Oncology Therapeutic Area Unit at Takeda. "The comprehensive data presented at ASH (Free ASH Whitepaper), from the pivotal VERIFY and long-term THRIVE studies, strongly underscore the potential of rusfertide to provide a sustained response, addressing a critical unmet need in managing this chronic cancer. We are excited to advance rusfertide towards regulatory approval in collaboration with Protagonist, bringing us one step closer to improving the care of patients suffering from PV."

Rusfertide has received Breakthrough Therapy Designation, Orphan Drug Designation and Fast Track Designation from the U.S. Food & Drug Administration (FDA).

About VERIFY
The Phase 3 VERIFY study (NCT05210790) is an ongoing, three-part, global, randomized, placebo-controlled study evaluating rusfertide in 293 patients with polycythemia vera over a 156-week period, with treatment extension for participants who are continuing to derive benefit from rusfertide beyond the 156-week treatment period. The study is evaluating the efficacy and safety of once-weekly, subcutaneously self-administered rusfertide in patients with uncontrolled hematocrit who are phlebotomy-dependent despite current standard of care treatment, which could include hydroxyurea, interferon and/or ruxolitinib. The primary endpoint of the study was the proportion of patients achieving a response during Weeks 20-32, which was defined as the absence of "phlebotomy eligibility." To meet phlebotomy eligibility, patients in the study were required to have: confirmed hematocrit ≥45% that was ≥3% higher than their baseline hematocrit value, or hematocrit ≥48%.

All patients have completed their participation in the randomized, placebo-controlled portion of the study evaluating the efficacy and safety of rusfertide plus current standard of care versus placebo plus current standard of care and are now in the open-label portions of the study.

About THRIVE
The THRIVE study (NCT06033586) is an ongoing, open-label extension study evaluating the long-term durability of response and safety profile of rusfertide in patients with polycythemia vera. The study includes 46 patients who previously participated in the Phase 2 REVIVE study (NCT04057040). Patients eligible to transition to the THRIVE study completed the open-label extension portion of REVIVE, ≥12 months of rusfertide therapy and had an end-of-treatment visit. THRIVE is designed to further assess the maintenance of hematocrit control, reduction in the need for therapeutic phlebotomy and overall safety of once-weekly, subcutaneous rusfertide over an additional two-year treatment period.

About Polycythemia Vera (PV)
Polycythemia vera (PV) is characterized by the overproduction of red blood cells (erythrocytosis), which increases blood viscosity, or thickness, that can result in life threatening thrombotic events such as stroke, deep vein thrombosis and pulmonary embolism. Hematocrit (HCT) is the ratio of red blood cells to total amount of blood in the body. Achieving and maintaining controlled HCT levels of <45% is the primary treatment goal in PV to prevent thrombotic events and alleviate burdensome symptoms, including severe fatigue, difficulty in concentrating, night sweats and pruritus.

(Press release, Takeda, DEC 6, 2025, View Source [SID1234661226])

On December 6, 2025 Kite, a Gilead Company (Nasdaq: GILD), reported Phase 1 data with encouraging efficacy and safety results for its two investigational bicistronic CAR T-cell therapies, KITE-753 and KITE-363, respectively, in patients with relapsed/refractory large B-cell lymphoma (R/R LBCL). The results of the analysis were shared in an oral presentation (Abstract #265) at the 67th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting and Exposition.

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Both KITE-753 and KITE-363 are bicistronic autologous CAR T-cell therapies. They are designed to target two antigens (CD19 and CD20) found on cancer cells and use two co-stimulatory domains (CD28 and 4-1BB) to help the immune system fight cancer more effectively. The KITE DuoCore construct – with two independent CARs working synergistically – may prevent relapse by reducing cancer cells escaping treatment and may help improve safety, making it possible to treat more patients outside of a hospital setting. Additionally, KITE-753 leverages a novel manufacturing process that preserves T-cell fitness. Combined, these attributes may contribute to better efficacy, lower toxicity, durable function, and faster delivery to patients.

"While CAR T-cell therapy has revolutionized treatment for many people with blood cancers, we urgently need options that not only improve upon the curative potential of existing cell therapies for evasive cancers but are also safer and available to a broader patient population," said Dr. Saurabh Dahiya, MD, FACP, the Stanford School of Medicine. "The encouraging response rates, durability and safety profile of KITE-753 and KITE-363 offer strong clinical evidence to support further development."

The open-label, multicenter, umbrella Phase 1 study enrolled 67 patients with R/R BCL. Thirty patients received KITE-753 and 37 received KITE-363.

Results for KITE-753 showed that at a median follow-up of 4.0 months overall and 2.9 months at dose level three (DL3; 0.2×106 CAR T cells/kg), 11 of 14 CAR-naïve patients (79%) receiving DL3 had a complete response, where the cancer completely disappeared. Bridging options in this Phase 1 study were limited to corticosteroid +/- radiation therapy, and all patients had measurable, active disease at the time of their infusion with KITE-753. No patients responded to these bridging therapy measures at DL3. Notably, KITE-753 demonstrated robust expansion despite a tenfold lower dose than DL3 of KITE-363 (2×106 CAR T cells/kg), which highlights the proliferative capacity of KITE-753. Across all dose levels, 14 of 20 CAR-naïve patients achieved a complete response.

Overall, KITE-753 showed an encouraging safety profile with no dose‑limiting toxicities. At DL3, no Grade ≥3 cytokine release syndrome (CRS) or immune effector cell‑associated neurotoxicity syndrome (ICANS) were observed; Grade ≥3 adverse events occurred in 95% of patients (primarily cytopenias), and serious Grade ≥3 adverse events occurred in 26% of patients. Across all dose levels, one Grade 3 CRS event (none Grade ≥4) and no Grade ≥3 ICANS events occurred.

"Kite is dedicated to pushing the boundaries of CAR T-cell therapy to deliver even greater impact and curative potential," said Dr. Gallia Levy, Senior Vice President, Global Head of Development at Kite. "By combining CD19/CD20 targeting with dual co‑stimulation, along with a manufacturing process resulting in a fit product, we aim to improve outcomes. Our goal is to bring CAR T to more patients, such as those with advanced disease who have exhausted other options, and to those who prefer to be treated in outpatient and in community oncology practice settings."

Meanwhile, results for KITE-363 revealed that at a median follow-up of 17.5 months, there was a durable benefit at the highest dose level (2×106 CAR T cells/kg) among CAR-naïve patients, with more than 70% of complete responders evaluable at 12 months remaining in remission. KITE-363 was generally well tolerated with no dose-limiting toxicities or severe side effects that required stopping the study. Grade ≥3 CRS occurred in one patient; Grade 3 ICANS occurred in two patients; no Grade ≥4 CRS/ICANS occurred.

About LBCL

Globally, large B-cell lymphoma (LBCL) is the most common type of non-Hodgkin lymphoma. In the United States, more than 18,000 people are diagnosed with LBCL each year. About 30–40% of patients with LBCL will need second-line treatment, as their cancer will either relapse (return) or become refractory (not respond) to initial treatment.

About the Study

Thirty patients received KITE-753 and 37 received KITE-363. The open-label, multicenter umbrella Phase 1 study enrolled eligible adults with R/R LBCL after ≥2 lines of therapy (patients with LBCL could have second-line primary refractory disease) in dose escalation (1A) and expansion (1B; LBCL only) cohorts. Following leukapheresis and lymphodepletion, patients received dose level (DL) 1, 2, or 3 of KITE-753 (3.0×104, 1.0×105, or 2.0×105 CAR T cells/kg, respectively) or KITE-363 (0.5×106, 1×106, or 2×106 CAR T cells/kg, respectively). Primary endpoints were incidence of dose-limiting toxicities (DLTs; Phase 1A) and investigator-assessed objective response rate (ORR; per Lugano; Phase 1B).

About KITE-753 and KITE-363

KITE-753 and KITE-363 are investigational, bicistronic autologous CAR T-cell therapies engineered to overcome tumor antigen heterogeneity and prevent relapse. The KITE DuoCore construct uniquely combines anti-CD19 and anti-CD20 targeting with dual co-stimulation (CD28 and 4-1BB). KITE-753 is an enhanced KITE DuoCore CAR T utilizing a novel manufacturing process, aiming to preserve T-cell fitness. Additionally, KITE-363 is being investigated for refractory autoimmune conditions.

(Press release, Gilead Sciences, DEC 6, 2025, View Source [SID1234661211])

On December 6, 2025 Deciphera Pharmaceuticals, a member of Ono Pharmaceutical Co., Ltd. (Headquarters: Osaka, Japan; President and COO: Toichi Takino; "Ono"), reported the oral presentation of positive results from the Phase 2a IMPRSSION study of sapablursen in patients with polycythemia vera (PV) at the 67th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting, taking place December 6-9, 2025, in Orlando, FL.

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The results were presented by Ionis Pharmaceuticals, who discovered and developed sapablursen and conducted the IMPRSSION study. In March 2025, Ionis and Ono entered into a license agreement in which Ono obtained exclusive global rights for the development and commercialization of sapablursen.

"In the treatment of PV, phlebotomy and cytoreductive therapy are performed as treatments for preventing thrombosis. Phlebotomy is the most common treatment for PV, in which blood is regularly removed from the vein, but it imposes significant physical and psychological burdens on patients. These Phase 2a study results demonstrate the ability of sapablursen to reduce the rate of blood withdrawals and control the hematocrit, which is the percentage of red blood cells in the total blood volume of the body, in phlebotomy-dependent patients including those undergoing cytoreductive therapy," said Tatsuya Okamoto, Corporate Officer / Executive Director, Clinical Development of Ono. "We believe sapablursen has the potential to be an important new treatment option for patients with PV and we look forward to advancing this promising treatment in a Phase 3 study."

Sapablursen was granted Fast Track designation in January 2024 and orphan drug designation in August 2024 by the U.S. Food and Drug Administration (FDA), along with Breakthrough Therapy designation in May 2025. Based on the positive Phase 2a study, Deciphera plans to initiate a Phase 3 study of sapablursen in patients with PV in 2026.

Summary of Data and Findings from Phase 2a IMPRSSION Study

The Phase 2a IMPRSSION study is a multicenter, randomized, open-label trial evaluating the safety and efficacy of sapablursen in patients with phlebotomy-dependent PV. Forty-nine (49) patients were accrued to Cohort A (N=32) and Cohort B (N=17). Cohort A initially assessed 120 mg before the dose was reduced to 80 mg, and Cohort B tested 40 mg. Sapablursen was administered subcutaneously every four weeks. The treatment period was 37 weeks, with an endpoint window between weeks 17 and 37, followed by a 36-week treatment extension period.

Efficacy

In both cohorts, the study achieved its primary endpoint of significantly decreasing weekly phlebotomy rate from baseline to weeks 17-37; with a decrease from 0.15 to 0.05 in Cohort A (p<0.0001) and from 0.17 to 0.07 in Cohort B (p=0.0001).
In patients who completed the 37-week treatment period, the median number of phlebotomies during the last 20 weeks of treatment (weeks 17-37) decreased to 0 and 1.5 phlebotomies in Cohort A and B, respectively, compared to 5 phlebotomies in the 26 weeks (6 months) prior to treatment for both cohorts.
Sapablursen caused a dose- and time-dependent increase in hepcidin with a corresponding reduction in hematocrit.
When assessing the symptoms of PV via Myeloproliferative Neoplasm Symptom Assessment Form – Total Symptom Score (MPN-SAF-TSS), the mean change from baseline was statistically significant in Cohort A and not statistically significant for Cohort B.
In Cohort A there was a mean change of -6.2.
In Cohort B there was a mean change of -2.7.
Safety

Sapablursen was generally safe and well tolerated.
During the study, one death occurred due to transformation to acute myeloid leukemia, which was deemed not related to the study drug.
The incidence of injection site reactions was low.
Injection site reactions were all mild in severity, not progressive, resolved spontaneously, and did not recur.
No laboratory trends suggesting adverse effects on liver or renal function were observed.
About Sapablursen

Sapablursen is designed to reduce the production of TMPRSS6 resulting in increased expression of hepcidin, which is the key regulator of iron homeostasis. By increasing production of hepcidin, sapablursen has the potential to positively impact blood diseases such as PV.

About Polycythemia Vera

Polycythemia vera (PV) is a rare and potentially life-threatening hematologic disease characterized by the overproduction of red blood cells, which significantly increases the risk of serious blood clots, especially in critical organs like the lungs, heart and brain. Patients with PV also experience severe iron deficiency and commonly have symptoms of fatigue, which can lead to reduced quality of life (QOL).

(Press release, Deciphera Pharmaceuticals, DEC 6, 2025, View Source [SID1234661227])

On December 6, 2025 Kite, a Gilead Company (Nasdaq: GILD), and its partner Arcellx, reported new positive data from its pivotal iMMagine-1 Phase 2 study of anitocabtagene autoleucel (anito-cel), an investigational agent, which continues to show clinically meaningful deep and durable efficacy with predictable and manageable safety observed to date in relapsed or refractory multiple myeloma (RRMM) patients who had received at least three prior lines of therapy. These new findings from the ongoing study will be shared in an oral presentation (Abstract #256) today at 2:45 PM ET during the 67th American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting and Exposition.

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"These data are compelling and are an important advancement for patients living with multiple myeloma," said Dr. Krina Patel, lead investigator, Associate Professor, Department of Lymphoma/Myeloma, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center. "I am encouraged by the depth of responses in the iMMagine-1 study. For clinicians, we rely on therapies that deliver continued meaningful efficacy, a predictable safety profile, and reliable manufacturing. Anito-cel demonstrates that it could become a significant new treatment option in our efforts to improve outcomes for patients with multiple myeloma."

Data from an October 7, 2025 cutoff date, including 117 patients treated with anito-cel, who were followed for a median of 15.9 months, showed an independent review committee (IRC)-assessed overall response rate (ORR) of 96%, with 74% achieving a stringent complete response or complete response (sCR or CR) per International Myeloma Working Group (IMWG) criteria. 102 of 117 patients (87%) were triple refractory, 48 of 117 patients (41%) were penta refractory, 21 of 117 patients (18%) had extramedullary disease, and 47 of 117 patients (40%) had high risk cytogenetics. For many in this heavily pre-treated population, responses began quickly, often within one month. Median time to best response was 4.8 months and median time to sCR or CR was 3.2 months. Of the 96 patients evaluable for minimal residual disease (MRD) testing, 91 (95%) achieved MRD negativity at a median time of 1 month, meaning no cancer cells could be detected even with highly sensitive tests (≤10-5 sensitivity).

The progression-free survival (PFS) rates were 82.1% at 12 months, 67.4% at 18 months and 61.7% at 24 months, meaning many patients were still alive and free from cancer progression at those timepoints. The overall survival (OS) rates showed that a significant majority of patients remained alive, with 94% at 12 months, 88% at 18 months and 83% at 24 months. The median PFS and OS have not yet been reached, suggesting sustained and ongoing benefit for a majority of patients.

Importantly, no delayed (non-ICANS) neurotoxicities, including no Parkinsonism, no cranial nerve palsies, no Guillain-Barré syndrome, and no immune effector cell-associated enterocolitis, have been observed to date, with all patients dosed at least 12 months prior to the cutoff. In an exploratory study sponsored by Kite (Abstract #503), characterization of CD4+ CAR T cell subtypes provide further mechanistic hypotheses supporting the neurologic tolerability profile of anito-cel.

"For multiple myeloma patients in advanced treatment stages, effective options are critical as resistance to treatment grows," said Cindy Perettie, Executive Vice President, Kite. "The deep, durable responses seen with iMMagine-1, combined with a predictable and manageable safety profile and rapid and reliable manufacturing, highlight anito-cel’s potential to redefine care. Together with Arcellx, our goal is to deliver a differentiated, one-time treatment option in 2026 that may reduce patient burden and improve access, including in outpatient and community oncology settings."

Observed side effects were generally consistent with past readouts. Cytokine release syndrome (CRS) was observed in 86% of patients but was generally mild and manageable. In fact, 83% of patients in the study experienced no CRS or Grade 1 CRS (fever only). Immune effector cell-associated neurotoxicity syndrome (ICANS) occurred in 8% of patients, with only one Grade 3 case and all other cases Grade 2 or lower. The most common hematologic adverse events noted during treatment were low white blood cell counts (neutropenia) in 71% of patients, low red blood cells (anemia) in 28%, and low platelets (thrombocytopenia) in 26%. Grade 3 or higher infections occurred in 9% of patients.

Additional research presented at ASH (Free ASH Whitepaper) provided further insights into CAR T-cell therapies, detailing anito-cel’s mechanism and factors influencing treatment outcomes.

Preclinical research (Abstract #7644) shows that anito-cel’s D-Domain binder interacts with BCMA by binding and releasing quickly. Relative to a comparator CAR T-cell therapy in preclinical models, this transient interaction with cancer cells may be associated with decreased inflammation while maintaining the ability to effectively kill cancer cells. Additionally, the abstract shows anito-cel retains its ability to target cancer cells with altered BCMA expression after previous treatments, demonstrating the potential for anito-cel to maintain efficacy in patients previously exposed to BCMA-targeting therapies. Further research, including crystallography and epitope mapping, is ongoing to provide more detail on this mechanism.

About anitocabtagene autoleucel (anito-cel)

Anitocabtagene autoleucel (anito-cel, previously ddBCMA) is the first BCMA-directed CAR T-cell therapy to be investigated in multiple myeloma that utilizes Arcellx’s novel and compact binder known as the D-Domain. The small, stable D-Domain binder enables high CAR expression without tonic signaling and is designed to quickly release from the BCMA target. This combination may allow for the effective elimination of multiple myeloma cells without severe immunotoxicity. Anito-cel has been granted Fast Track, Orphan Drug, and Regenerative Medicine Advanced Therapy Designations by the U.S. Food and Drug Administration.

About Multiple Myeloma

Multiple myeloma (MM) is a type of hematological cancer in which diseased plasma cells proliferate and accumulate in the bone marrow, crowding out healthy blood cells and causing bone lesions, loss of bone density, and bone fractures. These abnormal plasma cells also produce excessive quantities of an abnormal immunoglobulin fragment, called a myeloma protein (M protein), causing kidney damage and impairing the patient’s immune function. MM is the third most common hematological malignancy in the United States and Europe, representing approximately 10% of all hematological cancer cases and 20% of deaths due to hematological malignancies. The median age of patients at diagnosis is 69 years with one-third of patients diagnosed at an age of at least 75 years. Because MM tends to afflict patients at an advanced stage of life, patients often have multiple comorbidities and toxicities that can quickly escalate and become life-endangering.

About iMMagine-1

iMMagine-1 is a Phase 2 registrational, pivotal open-label study of anito-cel in patients with relapsed or refractory multiple myeloma (RRMM) who have received at least three prior regimens of systemic therapy including proteasome inhibitor, immunomodulatory drugs (IMiD) and anti-CD38 antibody and are refractory to the last line of therapy.

The trial assessed both safety and efficacy in 117 patients receiving a single infusion of anito-cel (target dose of 115×106 CAR+ viable T cells). Efficacy was assessed monthly for the first 6 months, then quarterly up to 2 years, or upon patient relapse. Long-term safety data will be collected under a separate long-term follow-up study for up to 15 years.

The primary endpoint is overall response rate (ORR) per International Myeloma Working Group (IMWG) criteria, as assessed by an independent review committee. Secondary endpoints include complete response rate (CR/sCR), progression-free survival, overall survival, duration of response, minimal residual disease negativity and safety.

(Press release, Gilead Sciences, DEC 6, 2025, View Source [SID1234661212])