Market Overview

Sunesis Announces Presentation of Positive Updated Results From Ongoing MD Anderson-Sponsored Trial of Vosaroxin in AML and High-Risk MDS at ASCO 2014 Annual Meeting


Sunesis Pharmaceuticals, Inc. (Nasdaq: SNSS) today announced the presentation of updated results from an ongoing Phase 1b/2 University of Texas MD Anderson Cancer Center-sponsored trial of Qinprezo™ (vosaroxin) in combination with decitabine in older patients with previously untreated acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS). The results will be presented today at the Leukemia, Myelodysplasia, and Transplantation General Poster Session of the American Society of Clinical Oncology Annual Meeting 2014 (ASCO) in Chicago, Illinois. The poster (Poster #383, S Hall A2) is titled "Phase I/II study of vosaroxin and decitabine in older patients with acute myeloid leukemia (AML) and high risk myelodysplastic syndrome (MDS)."

The Phase 1b/2 trial is expected to enroll up to a combined total of approximately 70 patients. As previously announced, the Phase 2 cohort was initiated in October 2013, following successful completion of a Phase 1b open-label, single-arm dose optimization phase. Patients in the ongoing trial are being followed for response, leukemia-free survival, overall survival and safety. Enrollment in the trial is ongoing.

To date, 34 patients (31 AML, 3 high-risk MDS) with a median age of 70 years (range, 41-78) have been enrolled; 97% were older than 60 years and 50% were older than 70 years. Of these, 30 patients were evaluable for response; 13 patients (43%) achieved complete response (CR), 6 patients (20%) achieved CR with incomplete platelet recovery (CRp), and 3 patients (10%) achieved CR with incomplete peripheral blood count recovery (CRi), for an overall response rate of 73%. Four patients are too early for response assessment. Patients have received a median of 2 (1 - 6) treatment cycles with median number of cycles to response being 1 (1 - 4). The main grade ≥ 3 toxicity was mucositis in 8 patients (24%). No patients died during the initial 30-day induction period.

Patients were also assessed for response by baseline characteristics, including mutation status. Among them, 6 patients had a documented mutation in isocitrate dehydrogenase-2 (IDH2) and 8 patients in tumor protein 53 (TP53, or mutational p53). The overall response rate among evaluable patients with IDH2 and TP53 mutations was 100% (6/6) and 63% (5/8), respectively.

"We remain encouraged by this study's high response rates in older patients with AML and high-risk MDS, a population frequently resistant to or intolerant of therapy," said Farhad Ravandi, M.D., Professor of Medicine, Department of Leukemia, University of Texas MD Anderson Cancer Center, and a study investigator. "In particular, the broad activity of Qinprezo and decitabine across AML mutational types is compelling. This unique breadth of activity, along with good tolerability, suggests the potential for a new treatment option for this underserved patient population."

"This study, which explores a novel combination with the hypomethylating agent decitabine, further supports the encouraging clinical profile of Qinprezo, a first-in-class, anti-cancer quinolone derivative," said Adam R. Craig, M.D., Ph.D., Executive Vice President, Development and Chief Medical Officer of Sunesis. "As we prepare for unblinding of the pivotal Phase 3 VALOR trial in first relapsed or refractory AML, expected in the third or fourth quarter of 2014, we will continue to work closely with experienced investigators to explore Qinprezo's value within other segments of the AML and MDS disease spectrum."

For the trial, patients are treated with Qinprezo (70 or 90 mg/m2) intravenously on days one and four in combination with decitabine (20 mg/m2) on days one to five. Vosaroxin dose is 70 mg/m2 in consolidation cycles, which are repeated in approximately four to five week intervals for a total of up to seven cycles. Dose adjustments and dose delays of one or both agents are allowed based on toxicity. Patients are eligible if they had AML or high-risk MDS (defined as having ≥ 10% blasts in the bone marrow), are 60 years of age or older, and have adequate performance status (ECOG ≤ 2) and organ function. Patients younger than 60 who are unsuited for standard chemotherapy are also eligible. The primary endpoint of the study is to determine the overall combined complete response rate. Secondary endpoints include CR duration, disease-free survival, overall survival, safety and early mortality.

The MD Anderson Cancer Center-sponsored trial is being conducted under the direction of Naval Daver, M.D., Assistant Professor, Department of Leukemia, University of Texas MD Anderson Cancer Center, and Dr. Ravandi. Dr. Ravandi is also a principal investigator of the Phase 3 VALOR trial, the company's randomized, double-blind, placebo-controlled, pivotal trial of Qinprezo plus cytarabine in patients with first relapsed or refractory AML.

About Qinprezo™ (vosaroxin)

Qinprezo™ (vosaroxin) is a first-in-class anti-cancer quinolone derivative (AQD), a class of compounds that has not been used previously for the treatment of cancer. Qinprezo both intercalates DNA and inhibits topoisomerase II, resulting in replication-dependent, site-selective DNA damage, G2 arrest and apoptosis. Both the U.S. Food and Drug Administration (FDA) and European Commission have granted orphan drug designation to vosaroxin for the treatment of AML. Additionally, Qinprezo has been granted fast track designation by the FDA for the potential treatment of relapsed or refractory AML in combination with cytarabine. Qinprezo is an investigational drug that has not been approved for use in any jurisdiction.

Posted-In: Press Releases


Related Articles (SNSS)

View Comments and Join the Discussion!
Lightning Fast
Market News Service
$199 Free 14 Day Trial

Alexion Initiates Voluntary Nationwide Recall of Certain Lots of Soliris® (eculizumab) Concentrated Solution for Intravenous Infusion Due to the Presence of Visible Particulate Matter in a Single Lot

Earnings Scheduled For June 2, 2014