Peregrine drug reportedly doubles lung cancer survival in trial

UPDATE 9/24/2012: Peregrine reports discrepancies with regard to the result reported below, causing stock price to plunge and confidence in bavituximab program to falter. For more, see story here.

TUSTIN, Calif.—Peregrine Pharmaceuticals Inc. announced Sept. 10 that interim results were presented from its 121-patient randomized, double-blind, placebo-controlled Phase IIb trial of bavituximab inpatients with refractory non-small cell lung cancer (NSCLC), with results that were strongly positive and the company felt warranted moving the compound toward Phase III trials.

The study evaluated two dose levels of bavituximab (the bavituximab-containingarms) given with docetaxel vs. docetaxel plus placebo (the control arm).The interim data showed a statistically significant improvement inoverall survival (Hazard Ratio 0.524, p-value .0154) and a doubling ofmedian overall survival in the bavituximab-containing arms comparedto the control arm.

"This study was a rigorous trial designed to minimize bias, and we areencouraged that this trial yielded such positive results in the mostimportant endpoint, overall survival. The positive overall responserates and progression free survival in both bavituximab-containing armsseen earlier in the study has now translated into a statisticallysignificant extension in overall survival for patients, a result rarelyachieved in phase II clinical trials." said Joseph Shan, vice presidentof clinical and regulatory affairs at Peregrine. "The quality of thisdata gives us a solid foundation for designing a phase III trial with anincreased probability of success. We are planning for an end-of-phaseII meeting with the FDA as we plan to initiate this trial by mid-2013."

The trial enrolled 121 patients (117 evaluable per the study protocol)with second-line non-squamous NSCLC following one prior chemotherapyregimen at over 40 clinical centers. Patients were equally randomized to one of the three treatment arms, docetaxel (75mg/m2) plus either placebo, 1mg/kg bavituximab, or 3 mg/kg bavituximab until disease progression.Approximately 50 percent of the patients were enrolled in the United States and the rest wereenrolled internationally, with equal distribution between all treatmentgroups.

"Robust data from this Phase II trial clearly demonstrate a significantbenefit in overall survival with a good safety profile in patientsreceiving bavituximab plus docetaxel compared to those receivingdocetaxel plus placebo," said Steven W. King, president and CEO of Peregrine. "We are currently in discussions withseveral potential pharmaceutical partners who have expressed greatinterest in our bavituximab oncology program. It is our goal to identifythe optimal partner to assist with the design and logistics of amultinational Phase III pivotal trial."

The interim results from the study showed no significant safetydifferences between the three treatment arms as determined by thetrial's independent data monitoring committee. Baseline characteristicswere well balanced across all three treatment arms of the study,including performance (ECOG) status, age, gender, and race. Tumorresponses were determined in accordance with Response EvaluationCriteria In Solid Tumors (RECIST 1.1) based on blinded central radiologyreview.

"The median overall survival results from the proof-of-concept study aretruly outstanding and great news for patients. Statisticallysignificant overall survival results at this stage of development arerare and have put us in an excellent position for advancing the program.Our attention is now turned to an end of phase II meeting by year endwhich will help us define the most efficient path forward to potentialregulatory approval," said Dr. Robert Garnick, head of regulatoryaffairs at Peregrine. "A global Phase III trial designed very similarlyto the robust design of this Phase II trial greatly increasesbavituximab's likelihood of success."