CHICAGO--(BUSINESS WIRE)-- Gilead Sciences, Inc. (Nasdaq:GILD) today announced results from the Phase 3 clinical Study 119 of an investigational use of Zydelig® (idelalisib) in combination with ofatumumab in previously-treated patients with chronic lymphocytic leukemia (CLL). In Study 119, there was a 73 percent reduction in the risk of disease progression or death in patients receiving Zydelig in combination with ofatumumab compared to ofatumumab alone (hazard ratio (HR) = 0.27; 95 percent CI: 0.19, 0.39; p<0.0001). Detailed results will be presented today during a poster session at the 51st Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago (Abstract #7023).
“The data reported today reinforce prior results showing that idelalisib, here in combination with the anti-CD20 monoclonal antibody ofatumumab, not only significantly improved overall and lymph node response rates, but more importantly progression-free survival in patients with previously treated CLL,” said Jeffrey A. Jones, MD, MPH, Associate Professor of Medicine, Division of Hematology, The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James). “Importantly, these improvements were also observed in patients with genetic features typically associated with poor prognosis.”
Study 119 was a randomized, controlled, open-label Phase 3 study evaluating the efficacy and safety of Zydelig in combination with ofatumumab. The study enrolled 261 adult patients with previously treated CLL whose disease had progressed less than 24 months following completion of prior therapy, and had not previously been refractory to ofatumumab. Eligible patients were randomized 2:1 to receive an ofatumumab 1,000 mg dosing regimen (12 infusions, first infusion 300mg) over 24 weeks plus Zydelig (150 mg) twice daily (n=174) continuously until disease progression or unacceptable toxicity or an ofatumumab 2,000 mg dosing regimen (12 infusions, first infusion 300mg) over 24 weeks (n=87).
The primary endpoint was progression-free survival (PFS), defined as the time from randomization to definitive disease progression or death assessed by an independent review committee. Median PFS in the Zydelig/ofatumumab arm was 16.3 months, compared to 8.0 months in the ofatumumab monotherapy arm. Statistically significant improvements were also observed for overall response rate (75 percent vs. 18 percent; odds ratio (OR) = 15.9, p<0.0001) and lymph node response rate (93.3 percent vs. 4.9 percent; OR=486.96, p<0.0001). Median PFS in the approximately 40 percent of patients with 17p deletion or TP53 mutation was 13.7 months vs. 5.8 months (HR=0.32, p<0.0001). A statistically significant difference was not achieved in median overall survival (20.9 months vs. 19.4 months; HR=0.74, p=0.27).
The safety profile of Zydelig was similar to prior studies in previously-treated patients with CLL. Grade ≥3 adverse events occurring in the Zydelig plus ofatumumab arm included diarrhea/colitis (20.2 percent), pneumonia (12.7 percent) and febrile neutropenia (11.6 percent).
Based on the Study 119 trial results, Gilead has filed a supplemental New Drug Application (sNDA) with the U.S. Food and Drug Administration to include data from this study in the U.S. label. Gilead plans to submit a supplemental filing to the European Medicines Agency later this year.
“Zydelig has now demonstrated strong efficacy in two randomized Phase 3 studies among previously treated CLL patients,” said Norbert Bischofberger, PhD, Gilead’s Executive Vice President, Research and Development and Chief Scientific Officer. “We continue to explore the clinical profile of Zydelig in combination with both standard and novel treatment regimens, including seven ongoing or completed Phase 3 clinical trials for B-cell malignancies.”
The Zydelig U.S. Prescribing Information includes a BOXED WARNING regarding fatal and serious toxicities of hepatotoxicity, severe diarrhea/colitis, pneumonitis, and intestinal perforation; see below for Important Safety Information.
The use of Zydelig in combination with ofatumumab is investigational and the safety and efficacy of this combination has not yet been established.
Dr. Jones is an uncompensated advisory board member to Gilead and receives research grant support to support this Phase 3 trial at The OSUCCC – James.
About Zydelig (idelalisib)
Zydelig is an oral inhibitor of phosphoinositide 3-kinase (PI3K) delta, a protein that plays a role in the activation, proliferation and viability of B cells, a critical component of the immune system. PI3K delta signaling is active in many B-cell leukemias and lymphomas, and by inhibiting the protein, Zydelig blocks several cellular signaling pathways that drive B-cell viability.
On July 23, 2014, Zydelig received accelerated approval from the U.S. Food and Drug Administration as monotherapy for patients with relapsed follicular lymphoma (FL) or small lymphocytic lymphoma (SLL) who have received at least two prior systemic therapies, and full approval in combination with rituximab for patients with relapsed CLL for whom rituximab alone would be considered appropriate therapy due to comorbidities. On September 19, 2014, the European Commission granted marketing authorization for Zydelig as monotherapy in FL patients who are refractory to two prior lines of treatment, and in combination with rituximab for CLL patients who have received at least one prior therapy, or in the presence of 17p deletion or TP53 mutation in patients unsuitable for chemoimmunotherapy.
Additional information about clinical studies of Zydelig and Gilead’s investigational cancer agents can be found at www.clinicaltrials.gov.
Important U.S. Safety Information
BOXED WARNING: FATAL AND SERIOUS TOXICITIES: HEPATIC, SEVERE DIARRHEA, COLITIS, PNEUMONITIS AND INTESTINAL PERFORATION
Warnings and Precautions
Dosage and Administration
About Gilead Sciences
Gilead Sciences is a biopharmaceutical company that discovers, develops and commercializes innovative therapeutics in areas of unmet medical need. The company’s mission is to advance the care of patients suffering from life-threatening diseases. Gilead has operations in more than 30 countries worldwide, with headquarters in Foster City, California.
This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors, including the risk that Gilead may be unable to submit a supplemental filing for the use of Zydelig in combination with ofatumumab to the EMA in the currently anticipated timelines. In addition, the regulatory filings may not be approved by the FDA, EMA and other regulatory agencies and marketing approvals, if granted, may have significant limitations on their use. As a result, Zydelig in combination with ofatumumab may never be successfully commercialized. Further, there is the possibility of unfavorable results from other clinical trials involving idelalisib. These risks, uncertainties and other factors could cause actual results to differ materially from those referred to in the forward-looking statements. The reader is cautioned not to rely on these forward-looking statements. These and other risks are described in detail in Gilead’s Quarterly Report on Form 10-Q for the quarter ended March 31, 2015, as filed with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation to update any such forward-looking statements.
U.S. full prescribing information, including BOXED WARNING for Zydelig is available at www.gilead.com.
Zydelig is a registered trademark of Gilead Sciences, Inc.
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