Xencor, Inc. (NASDAQ: XNCR), a clinical-stage biopharmaceutical
company developing engineered antibodies and cytokines for the
treatment of cancer and autoimmune diseases, today announced that
clinical data from expansion cohorts in its Phase 1 study of
plamotamab, a CD20 x CD3 bispecific antibody, in patients with
relapsed or refractory non-Hodgkin’s lymphoma will be presented in
a poster session during the 64th American Society of Hematology
(ASH) Annual Meeting in New Orleans, Louisiana on Monday, December
12, 2022.
“Plamotamab continues to be generally well tolerated and
demonstrates encouraging clinical activity in our recommended
intravenous dosing regimen,” said Allen Yang, M.D., Ph.D., senior
vice president and chief medical officer at Xencor. “Along with
Janssen scientists, we plan to advance plamotamab as part of highly
active chemotherapy-free regimens across B-cell cancers,
importantly with tumor-selective, co-stimulatory CD28 bispecific
antibodies. Xencor’s first combination study, evaluating plamotamab
in combination with tafasitamab plus lenalidomide, is enrolling
patients with advanced, aggressive lymphoma.”
Expansion cohorts in the Phase 1 study are actively recruiting
patients with diffuse large B-cell lymphoma (DLBCL) and follicular
lymphoma (FL) and are dosing using the proposed intravenous
recommended Phase 2 regimen to evaluate the safety and efficacy of
plamotamab monotherapy. The recommended dose (RD) was previously
identified as an intravenous, 50 mg flat dose every two weeks after
step-up dosing during the first two cycles of treatment.
Subcutaneous administration of plamotamab is currently being
incorporated into the study.
Key Highlights from the Abstract
The accepted abstract with data from the study is accessible
through the ASH website. Updated results will be shared at the ASH
Annual Meeting.
At data cut off on July 25, 2022, 36 patients with relapsed or
refractory non-Hodgkin’s lymphoma (NHL) had been enrolled on or
before April 1, 2022 and received the RD. Patients had a median age
of 67 years and had received a median of 4 prior therapies. At
baseline, 11.1% of patients had stage III disease, and 69.4% had
stage IV disease. Additionally, 50% of patients received CAR-T as a
prior therapy.
The safety analysis included all 36 patients. The most common
adverse event (AE) was cytokine release syndrome (CRS), which
occurred in 72.2% of patients, with no patients experiencing Grade
3 or 4 CRS. Grade 3 AEs affecting greater than 10% of patients
included anemia (19.4%), neutropenia (16.7%), neutrophil count
decrease (16.7%) and thrombocytopenia (11.1%). AEs leading to
plamotamab discontinuation occurred in five patients (13.9%).
The efficacy analysis included 25 evaluable patients at the RD.
In patients with diffuse large B-cell lymphoma (DLBCL), the overall
response rate (ORR) was 47.4% (9/19), and the complete metabolic
response/complete response (CMR/CR) rate was 26.3% (5/19). In
patients with follicular lymphoma, the ORR was 100% (6/6), and the
CMR/CR rate was 50% (3/6).
Prior CAR-T therapy was received by 18 patients, and 13
patients, all with DLBCL, were evaluable for efficacy. The ORR for
patients with prior CAR-T therapy was 46.2% (6/13), and the CMR/CR
rate was 30.8% (4/13).
An analysis of the plamotamab exposure-response (ER)
relationship from the dose-escalation portion of the Phase 1 study
examined IL6 levels, CRS incidence, high-grade AEs and ORR. The ER
analysis showed that during step-up dosing, the ratio of post-dose
maximum plamotamab concentration (Cmax) to minimum pre-dose
concentration (Ctrough) predicted CRS events, but in contrast, once
the target dose was reached, there was no relationship of exposure
to CRS. This analysis provides guidance for improving dosing
regimens in future clinical studies of plamotamab.
Presentation Details
- Abstract 4262, “A Phase 1 Study of Plamotamab, an Anti-CD20 x
Anti-CD3 Bispecific Antibody, in Patients with Relapsed/Refractory
Non-Hodgkin’s Lymphoma: Recommended Dose Safety-Efficacy Update and
Escalation Exposure-Response Analysis”
- Session: 626. Aggressive Lymphomas: Prospective Therapeutic
Trials: Poster III
- Date & Time: Monday, December 12, 2022. 6:00 - 8:00 p.m.
CST
- Location: Ernest N. Morial Convention Center, Hall D
About Plamotamab
Plamotamab is an investigational tumor-targeted XmAb® bispecific
antibody that contains both a CD20 binding domain and a cytotoxic
T-cell binding domain (CD3). CD20 is highly expressed across a
range of B-cell tumors, including non-Hodgkin lymphoma (NHL).
Engagement of CD3 by plamotamab activates T cells for highly potent
and targeted killing of CD20-expressing tumor cells.
Safety and anti-tumor activity from the ongoing Phase 1 clinical
study has indicated that plamotamab was generally well tolerated
and demonstrated encouraging clinical activity as a monotherapy.
Plamotamab is also being evaluated in a Phase 2 study, in
combination with tafasitamab plus lenalidomide, in patients with
relapsed or refractory diffuse large B-cell lymphoma. The study
consists of two parts, a safety run-in intended to establish the
safety of the triple combination and a two-arm, open-label cohort
where patients will be randomized to receive either the triple
combination or tafasitamab plus lenalidomide.
Xencor has entered an exclusive collaboration and worldwide
license agreement with Janssen Biotech, Inc. (Janssen) to develop
and commercialize plamotamab and novel XmAb B-cell targeting
bispecific antibodies that are designed to conditionally activate T
cells through the CD28 co-stimulatory receptor.
About Xencor
Xencor is a clinical-stage biopharmaceutical company developing
engineered antibodies and cytokines for the treatment of patients
with cancer and autoimmune diseases. More than 20 candidates
engineered with Xencor's XmAb® technology are in clinical
development, and three XmAb medicines are marketed by partners.
Xencor's XmAb engineering technology enables small changes to a
protein's structure that result in new mechanisms of therapeutic
action. For more information, please visit www.xencor.com.
Forward-Looking Statements
Certain statements contained in this press release may
constitute forward-looking statements within the meaning of
applicable securities laws. Forward-looking statements include
statements that are not purely statements of historical fact, and
can generally be identified by the use of words such as
“potential,” “can,” “will,” “plan,” “may,” “could,” “would,”
“expect,” “anticipate,” “seek,” “look forward,” “believe,”
“committed,” “investigational,” and similar terms, or by express or
implied discussions relating to clinical trial data for plamotamab
generally, planned clinical trials, the quotations from Xencor's
senior vice president and chief medical officer and other
statements that are not purely statements of historical fact. Such
statements are made on the basis of the current beliefs,
expectations, and assumptions of the management of Xencor and are
subject to significant known and unknown risks, uncertainties and
other factors that may cause actual results, performance or
achievements and the timing of events to be materially different
from those implied by such statements, and therefore these
statements should not be read as guarantees of future performance
or results. Such risks include, without limitation, the risks
associated with the process of discovering, developing,
manufacturing and commercializing drugs that are safe and effective
for use as human therapeutics and other risks, including the
ability of publicly disclosed preliminary clinical trial data to
support continued clinical development and regulatory approval for
specific treatments, in each case as described in Xencor's public
securities filings. For a discussion of these and other factors,
please refer to Xencor's annual report on Form 10-K for the year
ended December 31, 2021 as well as Xencor's subsequent filings with
the Securities and Exchange Commission. You are cautioned not to
place undue reliance on these forward-looking statements, which
speak only as of the date hereof. This caution is made under the
safe harbor provisions of the Private Securities Litigation Reform
Act of 1995, as amended to date. All forward-looking statements are
qualified in their entirety by this cautionary statement and Xencor
undertakes no obligation to revise or update this press release to
reflect events or circumstances after the date hereof, except as
required by law.
View source
version on businesswire.com: https://www.businesswire.com/news/home/20221103005406/en/
For Investors: Charles Liles cliles@xencor.com 626-737-8118
For Media: Jason I. Spark Evoke Canale
jason.spark@evokegroup.com 619-849-6005
Xencor (NASDAQ:XNCR)
Historical Stock Chart
From Feb 2024 to Mar 2024
Xencor (NASDAQ:XNCR)
Historical Stock Chart
From Mar 2023 to Mar 2024