Regeneron Pharmaceuticals, Inc. this week announced that the Company was informed by study investigators that a randomized, controlled trial evaluating four investigational therapies for Ebola virus infection was stopped early because REGN-EB3 was superior to ZMapp in preventing death. ZMapp served as the control arm of the trial because it was considered the standard-of-care based on the previous PREVAIL II clinical trial. The protocol specified that the PALM trial would only be stopped early for a highly statistically significant result. The independent data safety monitoring board decided to stop the trial after reviewing interim mortality data from 499 patients. The trial was conducted in the Democratic Republic of Congo (DRC), where the current outbreak is ongoing.
The epidemic, which was declared a public health emergency last month, has now infected about 2,800 known patients, killing more than 1,800 of them, according to the W.H.O.
“The Regeneron team worked tirelessly to discover, develop and produce REGN-EB3 in record time utilizing our VelocImmune®-based technologies,” said Neil Stahl, Ph.D., Executive Vice President of Research and Development at Regeneron. “We are moved to know our therapy is helping save the lives of people facing this deadly infectious disease. We look forward to reviewing the trial data and are working with governments and other collaborators, including BARDA, to make REGN-EB3 available for the current outbreak and future use.”
“This trial was conducted in difficult circumstances during a public health emergency, and we appreciate the efforts of the WHO and other experts to add REGN-EB3 to the trial,” said Sumathi Sivapalasingam, M.D., Senior Director, Early Clinical Development and Experimental Sciences at Regeneron. “This trial is a remarkable advance in the decades-long struggle to respond to Ebola and we appreciate the tremendous efforts of the many governmental and non-governmental organizations who made it possible.”
The trial was first initiated in 2018 with three treatment arms: mAb114, remdesivir and ZMapp. The trial protocol was amended after the World Health Organization (WHO) held an Ad-Hoc Expert Consultation to assess all preclinical and clinical data on available investigational products, and recommended the addition of REGN-EB3 as a fourth treatment arm.
By August 2019, the trial had enrolled nearly 700 participants across four Ebola Treatment Centers in the DRC. With the preliminary findings in 499 trial participants, REGN-EB3 and mAb114 will be the two investigational treatments given as part of an Extension Phase to further evaluate safety until final results of the clinical trial are known, after which an Expanded Access Phase will be initiated using the lead therapeutics from the trial.
“We are so very proud to have one of the world’s leading biotechnology companies, which invests in life-transforming medicines for people with serious diseases, as a member of the Business Council of Westchester,” said Marsha Gordon, President and CEO of the BCW. “We congratulate everyone who has worked so hard to develop this REGN-EB3 therapy, which is saving lives and providing hope across the globe. Westchester truly is the place where smart things are happening every day.”