SAN FRANCISCO, Dec. 7, 2020 /PRNewswire/ -- Nektar Therapeutics
(NASDAQ: NKTR) today announced two nonclinical data presentations
for NKTR-255, its IL-15 pathway agonist, at the 62nd
American Society of Hematology (ASH) Annual Meeting. The
presentations include an oral presentation of translational
research studies conducted in collaboration with researchers from
Dana-Farber Cancer Center.
NKTR-255 is an interleukin-15 (IL-15) receptor agonist that is
designed to expand both natural killer (NK) cells and memory CD8 T
cell populations. It is currently being evaluated in multiple
clinical studies in both hematological and solid tumors in
combination with agents that induce antibody-dependent cellular
toxicity (ADCC). In the hematological setting, NKTR-255 is being
tested in a Phase 1b/2 clinical study
as monotherapy and in combination with rituximab or daratumumab in
patients with multiple myeloma (MM) and non-Hodgkin's lymphoma
(NHL). It is also being evaluated in a Phase 1b/2 solid tumor trial in combination with
cetuximab for the treatment of colorectal cancer and head and neck
squamous cell carcinoma (HNSCC).
"Inhibition of NK cell effector functions is a mechanism for
immune evasion in patients with multiple myeloma and therefore
restoring and enhancing NK cell functionality is a key goal for new
immunotherapeutic approaches, " said Nikhil
C. Munshi, MD, Professor of Medicine at Harvard Medical School, Director of Basic and
Correlative Science, and Associate Director of the Jerome Lipper
Multiple Myeloma Center at Dana-Farber Cancer Institute. "In our
studies, we found the novel IL-15 receptor agonist, NKTR-255, was
effective in reverting the inhibitory status observed in NK cells
from MM patients, leading to enhanced direct NK cytotoxicity
against several MM cell lines and primary MM cells. In addition, we
saw a significant increase in ADCC activity in vitro with
NKTR-255 in combination with myeloma-targeting antibodies as
compared to activity with those antibodies alone. These data
accentuate the potential for NKTR-255 as an innovative
immunotherapeutic agent in the treatment of multiple myeloma."
"The ASH presentations add to the growing body of data for
NKTR-255 that highlight its ability to enhance NK cell effector
function and greatly potentiate the ADCC mechanisms of targeted
antibodies," said Jonathan Zalevsky,
Ph.D., Chief Research & Development Officer at Nektar. "We are
excited about the development potential of NKTR-255, especially as
we've already observed biological activity in the first multiple
myeloma and non-Hodgkin's lymphoma patients treated in the
monotherapy dose-escalation phase of our liquid tumor study."
Details of the preclinical data presentations at ASH are listed
below and are available on the scientific section of Nektar's
website at
http://www.nektar.com/science/scientific-posters-and-presentations:
Abstract 667: "Restoring NK Cell Activities in
Multiple Myeloma with IL-15 Receptor Agonist NKTR-255,"
Fernández, R. A., et al. (This study was conducted in collaboration
with Dr. Nikhil C. Munshi at the
Jerome Lipper Multiple Myeloma Center at Dana-Farber Cancer
Institute.)
- Oral Session: 652. Myeloma: Pathophysiology and
Pre-Clinical Studies, excluding Therapy
- Date: Monday, December 7,
2020, 2:30 p.m. Eastern Standard
Time
-
- The induction of an activated profile in NK cells by NKTR-255
results in an effective enhancement of their anti-myeloma effector
function in ex vivo assays.
- In vivo studies confirmed superiority of the combination
of daratumumab and NKTR-255 compared to single agents in
controlling MM growth.
- NKTR-255 improves the immune cell compartment both in the tumor
tissue and blood following anti-CD38 treatment.
Abstract 825: "Optimizing Ex-Vivo Expanded NK Cell-
Mediated Antibody-Dependent Cellular Cytotoxicity (ADCC) Combined
with NKTR-255 in Chronic Lymphocytic Leukemia (CLL), Follicular
Lymphoma (FL), and Burkitt Lymphoma (BL)," Chu, Y., et al.
(This study was conducted in collaboration with Dr. Mitchell Cairo at New York
Medical College.)
- Poster Session: 203. Lymphocytes, Lymphocyte
Activation, and Immunodeficiency, including HIV and Other
Infections: Poster I
- Date: Saturday, December 5,
2020, 7:00 a.m. – 3:30 p.m. Eastern Standard Time
-
- NKTR-255 significantly enhanced the in vitro
cytotoxicity of expanded NK cells when combined with rituximab
against MEC-1, PGA-1, and DOHH2 as compared to the control
groups.
- NKTR-255 also significantly enhanced the in vitro
cytotoxicity of expanded NK cells when combined with obinutuzumab
against rituximab-resistant BL cells like Raji-2R and Raji-4RH as
compared to the control groups.
- NKTR-255 significantly enhanced the ADCC of expanded NK cells
with anti-CD20 type I and type II antibodies against CLL, FL and
rituximab-resistant BL cells in vitro with enhanced IFN-γ, granzyme
B and perforin release.
About NKTR-255
NKTR-255 is an IL-15 receptor agonist designed to activate the
IL-15 pathway and expand NK cells and promote the survival and
expansion of memory CD8+ T cells without inducing suppressive
regulatory T cells. Through optimal engagement of the
IL-15Rα/IL-2Rβγ receptor complex, NKTR-255 enhances functional NK
cell population and formation of long-term immunological memory,
which may lead to sustained anti-tumor immune response. NKTR-255 is
uniquely designed to overcome the challenges of recombinant IL-15
and other IL-15 agonists, which are rapidly cleared from the body
and have shown diminishing response to successive
doses.1 NKTR-255 was designed using Nektar's polymer
conjugation technology to extend circulating half-life.
About Nektar
Nektar Therapeutics is a biopharmaceutical company with a
robust, wholly owned R&D pipeline of investigational medicines
in oncology, immunology, and virology as well as a portfolio of
approved partnered medicines. Nektar is headquartered in
San Francisco, California, with
additional operations in Huntsville,
Alabama and Hyderabad,
India. Further information about the company and its drug
development programs and capabilities may be found online at
http://www.nektar.com.
Cautionary Note Regarding Forward-Looking Statements
This press release contains forward-looking statements which can
be identified by words such as: "potential," "design," "enhance,"
"may," "test," "evaluate" and similar references to future periods.
Examples of forward-looking statements include, among others,
statements we make regarding the expected benefits of NKTR-255
(both alone as a single agent as well as in combination with other
agents, such as targeted antibodies), the ability to obtain useful
data from the Phase 1b/2 clinical
study of NKTR-255, and the future clinical development plans for
NKTR-255. Forward-looking statements are neither historical facts
nor assurances of future performance. Instead, they are based only
on our current beliefs, expectations and assumptions regarding the
future of our business, future plans and strategies, anticipated
events and trends, and other future conditions. Because
forward-looking statements relate to the future, they are subject
to inherent uncertainties, risks and changes in circumstances that
are difficult to predict and many of which are outside of our
control. Our actual results may differ materially from those
indicated in the forward-looking statements. Therefore, you should
not rely on any of these forward-looking statements. Important
factors that could cause our actual results to differ materially
from those indicated in the forward-looking statements include,
among others: (i) NKTR-255 is in early-stage clinical development
and there are substantial risks that can unexpectedly occur for
numerous reasons including negative safety and efficacy findings in
the Phase 1b/2 clinical study
notwithstanding positive preclinical findings; (ii) clinical study
outcomes, including the Phase 1b/2
clinical study outcome of NKTR-255, remain very unpredictable and
it is possible that a clinical study could fail due to efficacy,
safety or other important clinical findings; (iii) the timing of
the commencement or end of clinical trials and the availability of
clinical data may be delayed or unsuccessful due to regulatory
delays, slower than anticipated patient enrollment, manufacturing
challenges, changing standards of care, evolving regulatory
requirements, clinical trial design, clinical outcomes, and
competitive factors; (iv) scientific discovery of new therapeutics
is an inherently uncertain process and the future success of
applying our technology platform to potential new drug candidates
(such as NKTR-255) is therefore highly uncertain and unpredictable;
(v) patents may not issue from our patent applications for
NKTR-255, patents that have issued may not be enforceable, or
additional intellectual property licenses from third parties may be
required; and (vi) certain other important risks and uncertainties
set forth in Nektar's Quarterly Report on Form 10-Q filed with the
Securities and Exchange Commission on November 6, 2020. Any forward-looking statement
made by us in this press release is based only on information
currently available to us and speaks only as of the date on which
it is made. We undertake no obligation to update any
forward-looking statement, whether written or oral, that may be
made from time to time, whether as a result of new information,
future developments or otherwise.
Contact:
For Investors:
Jerry
Isaacson of Nektar Therapeutics
628-895-0634
Vivian Wu of Nektar Therapeutics
628-895-0661
For Media:
Dan Budwick
of 1AB
973-271-6085
dan@1abmedia.com
1. Blood 2018 Jun
7;131(23):2515-2527
View original
content:http://www.prnewswire.com/news-releases/nektar-therapeutics-announces-presentation-of-preclinical-data-for-nktr-255-its-novel-il-15-agonist-at-the-american-society-of-hematology-ash-2020-annual-meeting-301187695.html
SOURCE Nektar Therapeutics