Xencor to Present Data from Phase 1 Study of Vibecotamab in Acute Myeloid Leukemia at the 2020 ASH Annual Meeting

On November 4, 2020 Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies for the treatment of cancer and autoimmune disease, reported that data from the ongoing Phase 1 dose-escalation study of vibecotamab (XmAb14045), a CD123 x CD3 bispecific antibody, in patients with relapsed/refractory acute myeloid leukemia (AML) will be presented in an oral session at the 2020 American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting on Sunday, December 6, 2020 (Press release, Xencor, NOV 4, 2020, View Source [SID1234569874]).

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"Data from the Phase 1 study of vibecotamab suggest that patients with AML having low baseline disease burden and specific T-cell signatures may be more likely to respond to treatment with vibecotamab. The primary toxicity, CRS, is generally mild-to-moderate in severity when observed and is manageable," said Allen Yang, M.D., Ph.D., senior vice president and chief medical offer at Xencor. "We continue to optimize dosing regimen in this study, and along with our partner Novartis, we are planning our next clinical trials to develop vibecotamab in patients, for whom an intermittently dosed, CD123-targeting antibody could be a needed therapeutic option."

Key Highlights from the Abstract

The accepted abstract is available on the ASH (Free ASH Whitepaper) conference website.

At data cut off for submitting the abstract, 104 patients with AML, one patient with B cell acute lymphoblastic leukemia and one patient with chronic myeloid leukemia had received vibecotamab. Patients had a median age of 63 years and were heavily pretreated, having a median of three prior therapies, and 30% (n=32/106) had undergone prior allogeneic stem cell transplantation.
Patients received doses of vibecotamab ranging from 0.003 mcg/kg to 12 mcg/kg. The recommended initial priming dose was determined to be 0.75 mcg/kg. A maximum tolerated dose (MTD) was not reached.
Cytokine release syndrome (CRS) was the most common toxicity occurring in 58% of patients (n=62), and 8% of patients (n=9) experienced CRS at Grade 3 or higher. The majority of CRS was observed on the first dose and was generally manageable with premedication. Additional adverse events consistent with CRS but not reported as such, including chills, fever, tachycardia and hypotension, were reported in an additional 24% of patients. No myelosuppression requiring dose modification or evidence of tumor lysis syndrome was observed.
At dose levels of at least 0.75 mcg/kg (n=51), two patients achieved complete remission (CR), three patients achieved a CR with incomplete hematologic recovery, and two patients or morphologic leukemia-free state (ORR=14%).
Patients with responses were characterized by lower disease burden and specific T-cell subtypes.
Presentation Details

Abstract: 460
Title: Complete Responses in Relapsed/Refractory Acute Myeloid Leukemia (AML) Patients on a Weekly Dosing Schedule of Vibecotamab (XmAb14045), a CD123 x CD3 T Cell-Engaging Bispecific Antibody; Initial Results of a Phase 1 Study
Session: 613. Acute Myeloid Leukemia: Potpourri of Potential Practice Changing Studies
Date & Time: Sunday, December 6, 2020, 2:30 p.m. PST
About Vibecotamab

Vibecotamab (XmAb14045) is a tumor-targeted antibody that contains both a CD123 binding domain and a cytotoxic T-cell binding domain (CD3) in a Phase 1 clinical trial for the treatment of acute myeloid leukemia (AML) and other CD123-expressing hematologic malignancies. An XmAb Bispecific Fc domain serves as the scaffold for these two antigen binding domains and confers long circulating half-life, stability and ease of manufacture on vibecotamab. CD123 is highly expressed on AML cells and leukemic stem cells, and it is associated with poorer prognosis in AML patients. Engagement of CD3 by vibecotamab activates T cells for highly potent and targeted killing of CD123-expressing tumor cells.

Rocket Pharmaceuticals Reports Third Quarter 2020 Financial Results and Highlights Recent Progress

On November 4, 2020 Rocket Pharmaceuticals, Inc. (NASDAQ: RCKT) ("Rocket"), a clinical-stage company advancing an integrated and sustainable pipeline of genetic therapies for rare childhood disorders, reported financial results for the quarter that ended September 30, 2020, along with an update on the Company’s key pipeline developments, business operations and upcoming milestones (Press release, Rocket Pharmaceuticals, NOV 4, 2020, View Source [SID1234569873]).

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"We are incredibly pleased with the steady progress we made across all five of our clinical programs this quarter. The data from our RP-L201 trial for LAD-I demonstrated the potential for a very robust and attractive profile for our ‘Process B’ lentiviral gene therapy pipeline. We also treated our first higher dose patient in our Phase 1 study of RP-A501 for the treatment of Danon Disease, and presented compelling preclinical data in IMO," said Gaurav Shah, M.D., President and Chief Executive Officer of Rocket. "In addition, I am proud that against the backdrop of a global pandemic, while there have been some delays in patient follow up and data collection, we continued to enroll and treat patients in our LVV and AAV gene therapy programs as well as expand our clinical trials internationally. Finally, we made strong progress in the build-out of Rocket’s AAV R&D and manufacturing facility, with the ability to produce GMP product anticipated in 2021."

Dr. Shah continued, "We are looking forward to sharing additional updates as we enter the fourth quarter. These data announcements include an update on the Phase 1 and 2 trials for FA ‘Process B’, and for the first time, Phase 1 clinical data from our two largest indications: RP-L301 for PKD and RP-A501 for Danon Disease. We believe we are advancing closer to our goal of taking drug products from the discovery phase to BLA submission and launch so we may help improve the lives of patients facing these rare and devastating childhood diseases."

Key Pipeline Developments and Operational Updates

Positive clinical update for the Company’s Leukocyte Adhesion Deficiency Program (LAD-I) presented at the European Society for Immunodeficiencies (ESID) 2020 Meeting along with preclinical data from the Company’s Infantile Malignant Osteopetrosis (IMO) program.
An oral presentation provided positive longer-term follow-up data from the Phase 1/2 clinical trial of RP-L201 for LAD-I. The data presented in the oral presentation are from two pediatric patients with severe LAD-I, as defined by CD18 expression of less than 2%. Both patients were treated with RP-L201, Rocket’s ex-vivo lentiviral gene therapy candidate. Patient L201-003-1001 was 9 years of age at treatment and has been followed for 12 months and Patient L201-003-1004 was 3 years of age at treatment and has been followed for 4 months. Treatments were well tolerated, and no safety issues were reported with infusion or post-treatment. Both subjects achieved hematopoietic reconstitution in less than 4 weeks. Patient L201-003-1001 demonstrated durable CD18 expression of 40%, peripheral blood VCN levels of 1.3, visible signs of improvement in existing skin lesions and no new infections reported 12 months post-treatment. Patient L201-003-1004 demonstrated CD18 expression of 28% and early peripheral blood VCN trending similarly to the first patient, reported 4 months post-treatment.
An e-poster highlighted preclinical trial data on RP-L401 for IMO. Preclinical data on IMO indicate that a modest level of engraftment corrects the disease phenotype in vivo, with increased long-term survival, tooth eruption, weight gain and normalized bone resorption. Results support acceleration into clinical development for RP-L401.
First patient treated in the higher dose cohort of the Phase 1 dose-escalation clinical trial of RP-A501 for the treatment of Danon Disease. The first patient was treated at the higher dose level of 1.1×1014 genome copies/kilogram after clearance from the U.S. Food and Drug Administration (FDA) and the Independent Data Safety Monitoring Committee (IDSMC) to move to the higher dose cohort of the study. Preliminary Phase 1 data are anticipated in December assuming no further delays in patient data collection due to COVID-19.
Opened the Research & Development (R&D) and Chemistry, Manufacturing and Controls (CMC) facility in Cranbury, New Jersey. Approximately half of the newly constructed 103,720 square foot facility will be dedicated to adeno-associated virus (AAV) Current Good Manufacturing Practice (cGMP) manufacturing. As previously guided, the first cGMP clinical product release is expected in 2021.
Received additional regulatory designations for IMO and Danon Disease programs from U.S. Food and Drug Administration. RP-L401 gene therapy for IMO received Fast Track Designation and RP-A501 for Danon Disease received Rare Pediatric Disease Designation. The FDA’s Fast Track program facilitates the development of products intended to treat serious conditions that have the potential to address unmet medical needs. The designation enables greater access to the FDA for the purpose of expediting the product’s development, review and potential approval. The FDA grants Rare Pediatric Disease Designation for serious and life-threatening diseases that primarily affect children ages 18 years or younger and fewer than 200,000 people in the U.S.
Expanded clinical sites for Fanconi Anemia (FA), Danon, LAD-I and IMO trials, adding to global centers of excellence. The newly added centers, which include some of the leading gene therapy research programs in the world, include: Great Ormond Street Hospital (GOSH), Children’s Hospital of Philadelphia (CHOP), the University of Minnesota and the University of California, Los Angeles (UCLA). We anticipate these additional sites will expand patient access to Rocket’s clinical trials worldwide.
Hosted third Pyruvate Kinase Deficiency (PKD) Day in October. Continuing its commitment to the patient communities it serves, Rocket facilitated the first virtual edition of PKD Day. The event, intended for patients with PKD and their families, gave attendees an introduction to PKD, gene therapy and Rocket’s clinical program and provided time for a Q&A session with experts in the field and Rocket team members.
Anticipated Milestones

FA (RP-L102)
Preliminary "Process B" data (12/20)
Updated "Process B" data (1H21)
Danon Disease (RP-A501)
Preliminary Phase 1 data (12/20)
Updated Phase 1 data (2H21)
LAD-I (RP-L201)
Phase 2 data (1H21)
PKD (RP-L301)
Preliminary Phase 1 data (12/20)
Phase 1 data update (2H21)
IMO (RP-L401)
Phase 1 data (2H21)
Upcoming Investor Conferences

Piper Sandler 32nd Annual Healthcare Conference, December 1, 2020
Evercore ISI 3rd Annual HealthCONx Conference, December 2, 2020
Third Quarter Financial Results

Cash position. Cash, cash equivalents and investments as of September 30, 2020 were $228.7 million.
Debt. Our balance sheet includes $52.0 million of fully convertible notes.
R&D expenses. Research and development expenses were $21.7 million for the three months ended September 30, 2020, compared to $14.8 million for the three months ended September 30, 2019, primarily due to increases in manufacturing and development costs, clinical trial expenses, license fees, and compensation and benefit expenses due to increased R&D headcount.
G&A expenses. General and administrative expenses were $5.7 million for the three months ended September 30, 2020, compared to $4.3 million for the three months ended September 30, 2019, primarily due to increases in non-cash stock compensation expense and an increase in compensation and benefit expenses due to increased G&A headcount.
Net loss. Net loss was $29.0 million or $0.53 per share (basic and diluted) for the three months ended September 30, 2020, compared to $19.3 million or $0.38 per share (basic and diluted) for the three months ended September 30, 2019.
Shares outstanding. 55,204,127 shares of common stock were outstanding as of September 30, 2020.
Financial Guidance

Cash position. As of September 30, 2020, we had cash, cash equivalents and investments of $228.7 million. Rocket expects such resources will be sufficient to fund its operations into the second quarter of 2022.

100% Remission Rate Reported in Third Dose Cohort of Actimab-A CLAG-M Phase 1 Combination Trial in Patients with Relapsed or Refractory AML

On November 4, 2020 Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) ("Actinium") reported that 100% of evaluable patients in the third and planned final dose cohort of the Actimab-A CLAG-M Phase 1 trial being conducted at the Medical College of Wisconsin (MCW) achieved remission (Press release, Actinium Pharmaceuticals, NOV 4, 2020, View Source [SID1234569872]). Across all three cohorts, 67% or 10/15 patients treated with 0.25, 0.50 and 0.75 uCi/kg of Actimab-A and the standard regimen of CLAG-M achieved a Complete Remission (CR) or Complete Remission with inadequate hematopoietic recovery (CRi). Further, 83% of patients (10/12) who received 3 or fewer prior lines of treatment achieved CR or CRi. Notably, 70% of CR/CRi patients were MRD negative indicating a deep remission with no detectable disease. These results which include subtherapeutic doses of Actimab-A in the first two dose cohorts and represent a marked improvement over CLAG-M treatment alone (ORR: 55%, MRD negativity: 39%) implying potential mechanistic synergy. This novel Phase 1 combination trial is for patients with relapsed or refractory acute myeloid leukemia (R/R AML) age 18 and above deemed medically fit for cytotoxic chemotherapy. This data has been accepted for oral presentation at the 2020 American Society of Hematology (ASH) (Free ASH Whitepaper) annual meeting that is being held virtually December 5-8, 2020.

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Dr. Mark Berger, Actinium’s Chief Medical Officer, commented, "We are thrilled with the high rates of remission, MRD negativity and transplant in this trial, which highlights the potential this combination may have for patients with R/R AML. Actimab-A targets CD33, which is expressed in virtually all patients with AML, and delivers potent radiation via the alpha-emitting radioisotope Actinium-225. Actimab-A has produced single-agent response rates as high as 69% in a Phase 2 trial, demonstrating its potential in radiation sensitive blood cancers like AML. While the synergies of radiation with chemotherapy and other modalities is well known, we are highly encouraged that Actimab-A at low doses with CLAG-M produced higher rates of remission and MRD negativity than either agent alone, supporting the synergy of this combination and potential of other Actimab-A combinations. It’s still the case that there is no standard of care for R/R AML despite it being a large segment of the AML patient population. Our efforts with our CD33 program are intended to show that Actimab-A, when used together with other synergistic therapeutic modalities, can serve as the backbone of combinations that we hope will be new standards of care for both fit and unfit patients with R/R AML. With supporting data also being reported from our Actimab-A venetoclax combination trial we have great enthusiasm of the potential of additional Actimab-A combination with other therapeutic agents, that can treat patients with significant unmet need."

Patients enrolled on this study to date had intermediate (5/15, 33%) or adverse (10/15, 67%) cytogenetics. Patients received a median of 2 lines of prior therapies (range 1-5) with 47% of patients (7/15) previously receiving venetoclax with a hypomethylating agent and 53% of patients (8/15) having undergone an allogeneic BMT and then relapsed prior to Actimab-A CLAG-M. In the third dose cohort of 0.75 uCi/kg, 100% of evaluable patients (3/3) achieved complete remission [1 CR, 2 Complete Remission with inadequate platelet recovery (CRp)] with 2 patients being MRD negative and the other patient having only 0.2% AML cells detected. MRD negativity is defined as ≤0.1% AML cells. Investigators at MCW determined that the combination had a clinically acceptable safety profile, including at the planned final dose cohort of 0.75 uCi/kg, and have therefore amended this protocol to add a fourth dose cohort of 1.0 uCi/kg, which is currently screening and enrolling patients.

Dr. Berger added, "We look forward to continuing our work with the investigators at MCW in the expanded dose cohort. Given the complexity of treating patients with R/R AML we feel it is appropriate to continue to explore this novel combination to ensure we identify the ideal dose level. It is exciting to see the profile of this combination emerge not only for therapeutic purposes but also for its potential as a bridge to transplant as noted by the investigators at MCW."

Presentation Details

Oral Presentation Title:

A Phase I Study of Lintuzumab Ac225 in Combination with CLAG-M Chemotherapy in Relapsed/Refractory AML

Publication Number:

165

Session Name:

616. Acute Myeloid Leukemia: Novel Therapy, excluding Transplantation: Advances in immunotherapeutics for management of AML

Session Date:

Saturday, December 5, 2020

Presentation Time:

12:00 PM PT / 3:00 PM ET

The complete abstracts are available on the ASH (Free ASH Whitepaper) website (click here).

About Actinium’s CD33 Program

Actinium’s CD33 program is evaluating the clinical utility of Actiamb-A, an ARC comprised of the anti-CD33 mAb lintuzumab linked to the potent alpha-emitting radioisotope Actinium-225 or Ac-225. CD33 is expressed in the majority of patients with AML and myelodysplastic syndrome, or MDS, as well as patients with multiple myeloma. The CD33 development program is driven by data from over one hundred treated patients, including a Phase 1/2 trial where Actimab-A produced a remission rate as high as 69% as a single agent. This clinical data is shaping a two-pronged approach for the CD33 program, where at low doses the Company is exploring its use for therapeutic purposes in combination with other modalities and at high doses for use for targeted conditioning prior to bone marrow transplant. Actinium currently has multiple clinical trials ongoing including the Phase 1 Actimab-A CLAG-M and Phase 1/2 Actimab-A venetoclax combination trials and is exploring additional CD33 ARC combinations with other therapeutic modalities such as chemotherapy, targeted agents or immunotherapy.

Fortress Biotech Announces Oral and Poster Data Presentations at the 62nd American Society of Hematology (ASH) Annual Meeting

On November 4, 2020 Fortress Biotech, Inc. (NASDAQ: FBIO) ("Fortress"), an innovative revenue-generating company focused on acquiring, developing and commercializing or monetizing promising biopharmaceutical products and product candidates cost-effectively, reported that data from two of its clinical programs have been accepted for presentation at the 62nd American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting, which is being held virtually from December 5 – 8, 2020 (Press release, Fortress Biotech, NOV 4, 2020, View Source [SID1234569871]).

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Phase 2 data on Caelum Biosciences’ ("Caelum") CAEL-101 for the treatment of relapsed or refractory amyloid light chain "AL" amyloidosis will be presented by the Cleveland Clinic during oral and poster sessions. CAEL-101, which is being developed in a collaboration between Caelum, a company founded by Fortress, and Alexion Pharmaceuticals, Inc., recently progressed into Phase 3 development. In addition, interim Phase 1/2 data on Mustang Bio’s ("Mustang") MB-106, a CD20-targeted, autologous chimeric antigen receptor (CAR) T cell therapy for patients with relapsed or refractory B-cell non-Hodgkin lymphomas, will be presented by Mustang’s research partner Fred Hutchinson Cancer Research Center ("Fred Hutch") during a poster session.

Lindsay A. Rosenwald, M.D., Fortress’ Chairman, President and Chief Executive Officer, said, "We are looking forward to data from two of our clinical programs being presented in oral and poster sessions at the ASH (Free ASH Whitepaper) Annual Meeting. CAEL-101 and MB-106 are important product candidates that are poised to fill the urgent need for new treatment options and make a meaningful difference for patients."

Details of the presentations are as follows:

CAEL-101 Oral Presentation:

Title: Safety, Tolerability and Efficacy of CAEL-101 in AL Amyloidosis Patients Treated on a Phase 2, Open-Label, Dose Selection Study to Evaluate the Safety and Tolerability of CAEL-101 in Patients with AL Amyloidosis
Session: 653. Myeloma/Amyloidosis: Therapy, excluding Transplantation; Novel Approaches for Relapsed/Refractory Myeloma and Amyloidosis
Abstract: 729
Date and Time: Monday, December 7, 2020, 5:45 p.m. ET
Presenter: Jason Valent, M.D., Clinical Assistant Professor of Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University; Staff Department of Hematology and Oncology, Director Multiple Myeloma Program, Taussig Cancer Institute, Co-Director Amyloidosis Center
Cleveland Clinic

CAEL-101 Poster Presentation:

Title: CAEL-101 Is Well-Tolerated in AL Amyloidosis Patients Receiving Concomitant Cyclophosphamide-Bortezomib-Dexamethasone (CyborD): A Phase 2 Dose-Finding Study (NCT04304144)
Session: 653. Myeloma: Therapy, excluding Transplantation: Poster II
Abstract: 2277
Date and Time: Sunday, December 6, 2020, 10:00 a.m. – 6:30 p.m. ET
Presenter: Jason Valent, M.D., Clinical Assistant Professor of Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University; Staff Department of Hematology and Oncology, Director Multiple Myeloma Program, Taussig Cancer Institute, Co-Director Amyloidosis Center
Cleveland Clinic

MB-106 Poster Presentation:

Title: Third Generation CD20 Targeted CAR T-Cell Therapy (MB-106) for Treatment of Patients with Relapsed/Refractory B-Cell Non-Hodgkin Lymphoma
Session: 704. Immunotherapies: Poster I
Abstract: 1443
Date and Time: Saturday, December 5, 2020, 10:00 a.m. – 6:30 p.m. ET
Presenter: Mazyar Shadman, M.D., M.P.H., Associate Professor, Clinical Research Division, Fred Hutch, Seattle, WA

For more information, please visit the 62nd ASH (Free ASH Whitepaper) Annual Meeting and Exposition website at View Source

About CAEL-101 (Light Chain Fibril-reactive Monoclonal Antibody for AL Amyloidosis)
CAEL-101 is a first-in-class monoclonal antibody (mAb) designed to improve organ function by reducing or eliminating amyloid deposits in the tissues and organs of patients with AL amyloidosis. The antibody is designed to bind to misfolded light chain protein and amyloid and shows binding to both kappa and lambda subtypes. In a Phase 1a/1b study, CAEL-101 demonstrated improved organ function, including cardiac and renal function, in 27 patients with relapsed and refractory AL amyloidosis who had previously not had an organ response to standard of care therapy. CAEL-101 has received Orphan Drug Designation from both the U.S. Food and Drug Administration and European Medicine Agency as a therapy for patients with AL amyloidosis.

Actinium Announces Actimab-A Venetoclax First-in-Human Data Accepted for Poster Presentation at the 62nd American Society of Hematology Annual Meeting

On November 4, 2020 Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) ("Actinium") reported that data from the Phase 1 portion of the Actimab-A venetoclax Phase 1/2 combination trial, has been accepted for poster presentation at the 2020 American Society of Hematology (ASH) (Free ASH Whitepaper) annual meeting that is being held virtually December 5-8, 2020 (Press release, Actinium Pharmaceuticals, NOV 4, 2020, View Source [SID1234569870]).

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Poster Details & Highlights

Poster Title:

Lintuzumab-225Ac in Combination with Venetoclax in Relapsed/Refractory AML: Early Results of a Phase I/II Study

Publication Number:

2875

Session Name:

616. Acute Myeloid Leukemia: Novel Therapy, excluding Transplantation: Poster II

Session Date:

Monday, December 7, 2020

Presentation Time:

7:00 AM – 3:30 PM PT / 10:00 AM – 6:30 PM ET

Combining Actimab-A (225Ac lintuzumab) with venetoclax in patients with R/R AML has an acceptable initial clinical safety profile at the initial subtherapeutic dose level of 0.5 μCi/kg of Actimab-A.
A partial response was observed after a single cycle of Actimab-A and venetoclax.
Three R/R AML patients with a median age of 54 years (range 49-75) have been enrolled to date. The enrolled patients had a median of 2 therapies (2-3) and a median bone marrow blast percentage of 30% (range 20 – >60). All 3 patients had poor risk with adverse cytogenetics, and each patient has an additional high-risk marker (FLT3-ITD+, antecedent JAK2+ myelofibrosis, or TP53 mutation).
There have been no Actimab-A related dose limiting toxicities (DLT) or nonhematologic Grade 3 or greater related AEs.
Results in the first Actimab-A dose cohort are encouraging, and the trial will continue to enroll to evaluate the hypothesis that there will be clinical synergy consistent with pre-clinical results.
Dr. Mark Berger, Actinium’s Chief Medical Officer, said, "We have great excitement for this Actimab-A venetoclax combination trial and its potential for both fit and unfit patients with R/R AML. This preliminary first-in-human data is encouraging, particularly the reported patient response after a single cycle of venetoclax with a subtherapeutic dose level of Actimab-A. These initial results support the potential mechanistic synergy of Actimab-A with venetoclax and we are pleased by the progression in the clinic to the next dose level as there were no dose limiting toxicities with this combination."

Dr. Dale Ludwig, Actinium’s Chief Scientific and Technology Officer, stated, "We believe that the combination of low doses of Actimab-A with selected therapeutic modalities that together have potential mechanistic or complementary synergies is an approach that has great therapeutic potential. Therefore, it is exciting to see the hypothesized mechanistic synergy between Actimab-A and venetoclax, which we demonstrated in preclinical studies, now advancing in the clinic. Venetoclax as a single agent has produced low response rates in patients with R/R AML so we find it highly encouraging to see an initial response with a dose of Actimab-A that has shown to be subtherapeutic as a single agent. I am eager to see additional results from the first dose cohort as well as the second dose cohort to further support the therapeutic potential of Actimab-A in combination with venetoclax."

The complete abstracts are available on the ASH (Free ASH Whitepaper) website (click here).

About Actinium’s CD33 Program

Actinium’s CD33 program is evaluating the clinical utility of Actimab-A, an ARC comprised of the anti-CD33 mAb lintuzumab linked to the potent alpha-emitting radioisotope Actinium-225 or Ac-225. CD33 is expressed in the majority of patients with AML and myelodysplastic syndrome, or MDS, as well as approximately one third of patients with multiple myeloma. The CD33 development program is driven by data obtained from well over one hundred treated patients, including results from a Phase 1/2 trial that was conducted in 58 patients with newly diagnosed AML, which was completed in 2018. This clinical data, as well as the Company’s experience with Iomab-B, is shaping a two-pronged approach for the CD33 program, where at high doses the Company is exploring its use for targeted conditioning and at low doses the Company is exploring its use for therapeutic purposes as a single agent, or in combination with other modalities. There are currently multiple clinical trials ongoing studying Actimab-A including a Phase 1 combination trial with the salvage chemotherapy regimen CLAG-M, a Phase 1/2 trial in combination with venetoclax and its Actimab-MDS planned pivotal program for targeted conditioning with standard chemotherapy. In addition, Actinium is exploring additional combinations with Actimab-A and other potentially synergistic therapeutic modalities such as chemotherapy, targeted agents or immunotherapy.