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Actinium's Portfolio of Antibody Radiation-Conjugates to be Highlighted in Two Oral and Two Poster Presentations at the 2019 Society of Nuclear Medicine and Molecular Imaging Annual Meeting
- Pivotal Phase 3 Iomab-B program to be featured in oral presentations
- Effective lymphodepletion with the radioisotope Lutetium-177 expands Actinium's Iomab-ACT program for CAR-T and adoptive cell therapies to multiple warheads

NEW YORK, June 20, 2019 /PRNewswire/ -- Actinium Pharmaceuticals, Inc.  (NYSE AMERICAN: ATNM) ("Actinium") today announced its presence at the upcoming SNMMI or Society of Nuclear Medicine and Molecular Imaging 2019 Annual Meeting being held June 22nd – 25th in Anaheim, California. In total, two oral and two poster presentations highlighting Actinium's programs will be presented at SNMMI. In addition, Actinium's Chief Scientific Officer, Dr. Dale Ludwig, will participate in a panel at the Ac-225 User Group at SNMMI to discuss the use of the radioisotope Ac-225 or Actinium-225 produced by the of U.S. Department of Energy via a high-energy linear accelerator. Actinium has demonstrated feasibility in generating ARC's or Antibody Radiation-Conjugates with linear accelerator produced Ac-225.

Actinium's lead program, Iomab-B, which is being studied in the pivotal Phase 3 SIERRA trial, will be highlighted in two oral presentations at SNMMI. The two oral presentations will focus on the dosimetry of Iomab-B, which is used to tailor personalized doses for each patient in the SIERRA trial. Dosimetry allows for high levels of the isotope I-131 or Iodine-131 to be delivered in a patient specific doses, which has facilitated engraftment in all patients that received Iomab-B and a BMT or Bone Marrow Transplant in the first 25% of patients enrolled in the SIERRA trial. In addition, findings from a multi-center team suggest that dosimetry imaging optimization may be possible with Iomab-B, which could result in benefits for patients and treatment centers including a reduction in the number and time required for imaging.

The two poster presentations will highlight Actinium's AWE or Antibody Warhead Enabling Technology Platform that Actinium utilizes to empower its pipeline of ARC's. A poster will highlight the ARC comprised of the anti-CD38 antibody daratumumab, which is marketed as Darzalex® by Johnson & Johnson for patients with Multiple Myeloma, labeled with the radioisotope actinium-225. In addition, a poster presentation will highlight Actinium's expansion of its Iomab-ACT for lymphodepletion prior to CAR-T and other adoptive cell therapies. Actinium's Iomab-ACT program, which is a lower dose of Iomab-B, is intended to eliminate chemotherapy based conditioning agents such as Flu/Cy or Fludarabine and Cyclophosphamide. The poster will highlight the use of the radioisotope Lu-177 or Lutetium-177 with an anti-CD45 antibody, which has the potential to expand the radioisotope warheads that Actinium can utilize to achieve lymphodepletion prior to CAR-T and other adoptive cell therapies with its ARC's. The poster at SNMMI will be the first time that Actinium is presenting data on the use of Lu-177 with a CD45 targeting moiety.

Details of the SNMMI presentations are as follows:

Oral Presentations:

Session Title: SS51: Other Solid Tumors/ Hematologic Malignancies (Clinical) I
Date & Time: Tuesday, June 25th, 8:00 AM - 9:30 AM
Location: Room 202AB, Anaheim Convention Center

Publication 433
Presenter: Neeta Pandit-Taskar MD, Memorial Sloan Kettering Cancer Center
Time: 9:10-9:20 AM
Title: Optimizing Dosimetry Imaging in High dose Radioimmunotherapy Using the Novel, AntiCD45 Reinduction and Targeted Conditioning Agent Iodine (131I) Apamistamab [IomabB] in Patients 55 Years or Older with Active, Relapsed or Refractory Acute Myeloid Leukemia (SIERRA Phase III Trial)

Publication 434
Presenter: Neeta Pandit-Taskar MD, Memorial Sloan Kettering Cancer Center (on behalf of first author Landis Griffeth MD, Baylor University Medical Center)
Time: 9:20-9:30 AM
Title: Personalized Dosimetry using 131I-anti-CD45-Apamistamab (Iomab-B) Prior to High-dose Myeloablative Radioimmunotherapy for Hematopoietic Stem Cell Transplant (HCT) in Active, Relapsed, or Refractory Acute Myelogenous Leukemia: Novel Re-induction and Targeted Conditioning Feasibility and Engraftment Results from the SIERRA Trial

Poster Presentations:

Session Title: MTA I: Oncology, Basic and Translational (Basic Science) Posters
Date & Time: Monday, June 24th, 3:00 PM4:30 PM
Location: Poster Hall, Exhibit Hall, Anaheim Convention Center

Poster 1410
Presenter: Dr. Ekaterina Dadachova, University of Saskatchewan
225Ac-CD38 antibody targeting is effective and well tolerated in experimental models of lymphoma and multiple myeloma

Poster 1420
Presenter: Dr. Dale Ludwig, Actinium Pharmaceuticals, Inc.
Modeling targeted lymphodepletion with 177Lu-radiolabeled CD45 antibody as a preparative regimen prior to adoptive cell therapy

Ac-225 User Group at SNMMI
Date and Time: Sunday, June 23rd 4:00 – 5:00 PM PT
Location: Platinum Ballroom Salon 3 in Anaheim Marriott

About Actinium Pharmaceuticals, Inc.

Actinium Pharmaceuticals, Inc. is a clinical-stage biopharmaceutical company focused on improving patient access and outcomes to cellular therapies such as BMT or Bone Marrow Transplant and CAR-T with its proprietary ARC or Antibody Radiation-Conjugate targeted conditioning technology. Actinium is also developing its proprietary AWE or Antibody Warhead Enabling technology platform, which utilizes radioisotopes including iodine-131 and the highly differentiated actinium-225 coupled with antibodies, to target a variety of antigens that are expressed in hematological and solid tumor indications. It is developing a multi-disease, multi-target pipeline of clinical-stage ARC's targeting the antigens CD45 and CD33 for targeting conditioning and as a therapeutic either in combination with other therapeutic modalities or as a single agent for patients with a broad range of hematologic malignancies including Acute Myeloid Leukemia (AML), Myelodysplastic Syndrome (MDS) and Multiple Myeloma (MM). Actinium's lead product candidate, Iomab-B, is in a pivotal Phase 3 trial for re-induction and conditioning prior to a BMT for patients with active relapsed or refractory AML or Acute Myeloid Leukemia. BMT is the only curative treatment option for this patient population and currently no standard of care exists. Actimab-MDS is its second pivotal program for targeted conditioning that will study the ARC comprised of the anti-CD33 monoclonal antibody lintuzumab linked to the radioisotope actinium-225 in patients with high-risk MDS in combination with RIC or Reduced Intensity Conditioning prior to a BMT.  Its Iomab-ACT program utilizes a lower dose of Iomab-B (CD45 – I-131) that is intended to be used for targeted conditioning or lymphodepletion prior to CAR-T and adoptive cell therapies as a replacement to non-optimized chemotherapies, such a Flu/Cy or fludarabine and cyclophosphamide, that is used in standard practice today. Actinium also has multiple clinical trials ongoing, in startup phase, or in planning, to use its CD33 ARC in combination with other therapeutic modalities such as chemotherapy, targeted agents or immunotherapy. It has initiated several combination trials, including a doublet combination trial with its CD33 ARC and venetoclax, a BCL-2 inhibitor, for patients with relapsed or refractory AML, a triplet combination trial with venetoclax and an HMA or hypomethylating agent and in combination with the salvage chemotherapy regimen CLAG-M (cladribine, cytarabine, filgrastim and mitoxantrone) for patients with relapsed or refractory AML. Actinium is also studying its CD33 ARC as single agent for patients with penta-refractory multiple myeloma. Its AWE technology platform enables Actinium's internal pipeline and with the radioisotope actinium-225 is being utilized in a collaborative research partnership with Astellas Pharma, Inc. Actinium's clinical programs and AWE technology platform are covered by a portfolio of over 110 patents covering composition of matter, formulations, methods of use, the DOTA linker technology for actinium-225 applications and methods of manufacturing the actinium-225 radioisotope in a cyclotron.

Forward-Looking Statements for Actinium Pharmaceuticals, Inc. 

The information in this press release contains forward-looking statements regarding future events, including statements about Actinium's expectations regarding the terms of the offering or completion of the offering.  Actinium intends such forward-looking statements to be covered by the safe harbor provisions contained in Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Actual results or developments may differ materially from those projected or implied in these forward-looking statements. Factors that may cause such a difference include, without limitation, risks and uncertainties related to market and other conditions, the satisfaction of customary closing conditions related to the offering and the impact of general economic, industry or political conditions in the United States or internationally. There can be no assurance that Actinium will be able to complete the offering on the anticipated terms, or at all. More information about the risks and uncertainties faced by Actinium are more fully detailed under the heading "Risk Factors" in Actinium's Annual Report on Form 10-K for the year ended December 31, 2018 filed with the SEC. You should not place undue reliance on these forward-looking statements, which apply only as of the date of this press release. Except as required by law, Actinium assumes no obligation to update publicly any forward-looking statements, whether as a result of new information, future events or otherwise.

Contacts:

Actinium Pharmaceuticals, Inc. 
Steve O'Loughlin
Principal Financial Officer
investorrelations@actiniumpharma.com

Hans Vitzthum
LifeSci Advisors, LLC
Hans@LifeSciAdvisors.com 
(617) 535-7743

SOURCE Actinium Pharmaceuticals, Inc.