|Seattle Genetics Initiates Phase 1/2 Trial of Vadastuximab Talirine (SGN-CD33A) Combination Therapy for Patients with Untreated Myelodysplastic Syndrome (MDS)|
-Broad 33A Clinical Development Program Underway in Acute Myeloid Leukemia (AML) and MDS-
“Most newly diagnosed patients with intermediate or high risk MDS are
ineligible for allogeneic stem cell transplant due to age, comorbidities
or lack of appropriate donor. For these patients, novel therapies are
urgently needed to prolong survival and delay disease progression into
The phase 1/2, open-label, multi-center clinical trial is designed to evaluate the safety and activity of 33A administered in combination with azacitidine in patients with previously untreated International Prognostic Scoring System (IPSS) Intermediate-2 or high risk MDS. Phase 1 of the study will identify the recommended dose of 33A when combined with azacitidine in this patient population. The phase 2 portion of the trial will be a randomized, double-blind, placebo-controlled study evaluating azacitidine with or without 33A.
The primary endpoint in phase 1 is determination of the recommended 33A
dose in combination with azacitidine. The primary endpoint in phase 2 is
to compare the overall response rate between the two treatment arms. The
secondary endpoints include evaluation of safety, best response,
duration of response, progression-free survival and overall survival.
The phase 1/2 trial will enroll approximately 130 patients at
approximately 35 centers in
In addition to this MDS trial,
Additionally, a phase 3 clinical trial to evaluate 33A in combination with HMAs in previously untreated older AML patients is planned to begin by the third quarter of 2016.
More information about SGN-CD33A and ongoing clinical trials can be found at www.ADC-CD33.com.
With more than 15 years of experience and innovation,
For more information about the trial, including enrolling centers, please visit www.clinicaltrials.gov.
About Myelodysplastic Syndrome
Myelodysplastic Syndromes (MDS) are a group of diverse bone marrow
disorders in which the bone marrow does not produce enough healthy blood
cells. MDS is often referred to as a “bone marrow failure disorder”. MDS
is a disorder that starts when abnormal progenitor cells in the bone
marrow are damaged and have problems making new blood cells. Blood cells
formed by the abnormal bone marrow cells are defective. Defective cells
often have reduced survival and function, resulting in low blood counts
and abnormal behavior. In advanced MDS, blasts are detectable in the
bone marrow and usually express CD33. In about one-third of patients,
MDS can progress to a rapidly growing cancer of the bone marrow cells
called acute myeloid leukemia, or AML. According to the
About Vadastuximab Talirine (SGN-CD33A)
Vadastuximab talirine (SGN-CD33A; 33A) is a novel ADC targeted to CD33 utilizing Seattle Genetics’ newest ADC technology. CD33 is expressed on most AML and MDS blast cells. The CD33 antibody is attached to a highly potent DNA binding agent, a pyrrolobenzodiazepine (PBD) dimer, via a proprietary site-specific conjugation technology to a monoclonal antibody with engineered cysteines (EC-mAb). PBD dimers are significantly more potent than systemic chemotherapeutic drugs and the site-specific conjugation technology (EC-mAb) allows uniform drug-loading of the cell-killing PBD agent to the anti-CD33 antibody. The ADC is designed to be stable in the bloodstream and to release its potent DNA binding agent upon internalization into CD33-expressing cells. 33A is being evaluated in ongoing phase 1 and phase 1/2 clinical trials in AML and MDS and a planned pivotal phase 3 clinical trial for patients with AML.
Certain of the statements made in this press release are forward
looking, such as those, among others, relating to the therapeutic
potential of vadastuximab talirine (SGN-CD33A; 33A) and anticipated
clinical trials including potential patient and site enrollment. 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 the inability to show sufficient activity in this
recently initiated clinical trial and the risk of adverse events as
SGN-CD33A advances in clinical trials and regulatory actions. More
information about the risks and uncertainties faced by