- Represents first ever triplet combination using targeted
radiotherapy as a backbone therapy in AML with initial
clinical data expected in 2H:2025
- Expansion into frontline setting greatly expands potential
addressable patient opportunity for Actimab-A
- Triplet combination supported by previously completed Phase 1
trials of Actimab-A + Venetoclax and Actimab-A + CLAG-M
demonstrating Actimab-A's mutation agnostic and synergistic
potential
NEW
YORK, March 11, 2025 /PRNewswire/ -- Actinium
Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) (Actinium or the
Company), a pioneer in the development of targeted radiotherapies,
today announced that the first clinical trial under its previously
announced Cooperative Research and Development Agreement (CRADA)
with the National Cancer Institute (NCI) for Actimab-A has been
initiated. The trial (NCT06802523) will evaluate the triplet
combination comprised of Actimab-A, Venetoclax (Abbvie/Roche) an
oral Bcl-2 inhibitor and ASTX-727 (Taiho Oncology, an Otsuka
holdings company) a novel oral hypomethylating agent (HMA) in
frontline acute myeloid leukemia (AML) patients. Venetoclax in
combination with HMAs (Ven-HMA) is approved for patients with newly
diagnosed AML. Actimab-A, a humanized anti-CD33 antibody conjugated
to Actinium-225 (Ac-225) targets CD33, a marker expressed
ubiquitously on myeloid blasts in patients with AML and other
hematologic malignancies. The potent alpha-particle payload Ac-225
causes lethal double strand DNA breaks for which there are no known
resistance or repair mechanisms. This study will evaluate the rate
and duration of Complete Remission (CR), as well as safety,
including the optimal dose of Actimab-A in combination with
Venetoclax and ASTX-727 for potential future studies.
Dr. Avinash Desai, Actinium's
Chief Medical Officer, commented, "We are incredibly excited that
the first Actimab-A trial initiated under our CRADA with the NCI is
this triplet combination with Venetoclax and Taiho's ASTX-727.
While Ven-HMA has positively impacted outcomes in AML, a
significant number of patients have poor responses or relapse
quickly resulting in dismal outcomes. We believe Actimab-A's
potentially synergistic, and mutation agnostic mechanism of action
can improve clinical outcomes for these patients by producing
deeper remissions, including measurable residual disease
negativity, that are more durable. Due to its mutation agnostic
mechanism, Actimab-A can overcome high-risk features, such as TP53
mutations, and has demonstrated the ability to improve outcomes in
these patients where Ven-HMA has had limited success. This triplet
regimen can be conveniently administered in the outpatient setting
as Venetoclax and ASTX-727 are both oral agents and Actimab-A does
not require isolation given that it is an alpha-particle emitter.
We are eager to collaborate with NCI on this important study to
evaluate earlier intervention with a CD33 targeted radiotherapy in
patients with AML."
Actimab-A in combination with Venetoclax was previously studied
in a multi-center Phase 1 trial. The combination was shown to be
well tolerated with manageable adverse events. Preclinical studies
showed that Actimab-A can synergize with Venetoclax by depleting
MCL-1, which mediates Venetoclax resistance.
Sandesh Seth, Actinium's Chairman
& CEO, said, "We believe 2025 will be a transformational year
for Actimab-A and that the initiation of this triplet trial is a
significant catalyst. It is our objective to establish Actimab-A as
a backbone therapy across the treatment continuum of AML and other
myeloid malignancies leveraging the broad expression of CD33 and
the mutation agnostic Ac-225 payload. Driven by the compelling
clinical results in over 150 patients in multiple treatment
settings and the high visibility of our NCI CRADA, we are seeing
strong enthusiasm from investigators for Actimab-A. As the only
CD33 targeted radiotherapy in development for myeloid malignancies,
we are focused on capitalizing on the tremendous opportunity to
improve outcomes for a significant patient population that
continues to have high unmet medical needs that are not addressed
by current therapies. Over the course of 2025, we expect to
generate preclinical data and initiate additional clinical trials
that will further differentiate Actimab-A and demonstrate material
progress in establishing Actimab-A as a first-in-class backbone
radiotherapy for the over 100,000 patients with AML and other
myeloid malignancies in the U.S. and other major international
markets."
About Actinium Pharmaceuticals, Inc.
Actinium is a pioneer in developing targeted radiotherapies
intended to meaningfully improve patient outcomes. Actinium is
advancing its lead product candidate Actimab-A, a CD33 targeting
therapeutic ARC as potential backbone therapy in acute myeloid
leukemia (AML) and other myeloid malignancies leveraging the
mutation agnostic alpha-emitter radioisotope payload Actinium-225
(Ac-225). Actimab-A has demonstrated potential activity in relapsed
and refractory acute myeloid leukemia (r/r AML) patients in
combination with the chemotherapy CLAG-M including high rates of
Complete Remissions (CR) including measurable residual disease
(MRD) negativity with improved survival outcomes. In addition,
Actinium is engaged with the National Cancer Institute (NCI) under
the Cooperative Research and Development Agreement (CRADA) for
development of Actimab-A in AML and other myeloid malignancies.
Iomab-ACT, Actinium's next generation conditioning candidate, is
being developed with the goal of improving patient access and
outcomes for potentially curative cell and gene therapies. Iomab-B
is an induction and conditioning agent prior to bone marrow
transplant in patients with r/r AML, which Actinium is seeking a
potential strategic partner for in the U.S. In addition, the
company's R&D efforts are primarily focused on advancing
several preclinical programs for solid tumor indications. Actinium
holds 230 patents and patent applications including several patents
related to the manufacture of the isotope Ac-225 in a
cyclotron.
For more information, please
visit: https://www.actiniumpharma.com/
Forward-Looking Statements
This press release may contain projections or other
"forward-looking statements" within the meaning of the
"safe-harbor" provisions of the private securities litigation
reform act of 1995 regarding future events or the future financial
performance of the Company which the Company undertakes no
obligation to update. These statements are based on management's
current expectations and are subject to risks and uncertainties
that may cause actual results to differ materially from the
anticipated or estimated future results, including the risks and
uncertainties associated with preliminary study results varying
from final results, estimates of potential markets for drugs under
development, clinical trials, actions by the FDA and other
governmental agencies, regulatory clearances, responses to
regulatory matters, the market demand for and acceptance of
Actinium's products and services, performance of clinical research
organizations and other risks detailed from time to time in
Actinium's filings with the Securities and Exchange Commission (the
"SEC"), including without limitation its most recent annual report
on form 10-K, subsequent quarterly reports on Forms 10-Q and Forms
8-K, each as amended and supplemented from time to time.
Investors:
investorrelations@actiniumpharma.com
View original content to download
multimedia:https://www.prnewswire.com/news-releases/actinium-pharmaceuticals-announces-initiation-of-actimab-a-triplet-combination-frontline-trial-under-nci-crada-with-venetoclax-and-taiho-oncologys-hypomethylating-agent-astx-727-in-patients-with-newly-diagnosed-aml-302397827.html
SOURCE Actinium Pharmaceuticals, Inc.
