Biogen Idec has ended development of its dexpramipexole for amyotrophic lateral sclerosis ( ALS or Lou Gehrig’s disease), after the drug candidate failed a pivotal Phase III clinical trial—though the company insisted that it remains committed to ALS research.
Dexpramipexole failed to demonstrate efficacy in primary and key secondary endpoints of the EMPOWER clinical trial, according to top-line results shared by Biogen Idec yesterday. The study’s primary endpoint was efficacy in individual components of function or survival as measured by the Combined Assessment of Function and Survival (CAFS).
In addition to CAFS, the trial individually evaluated measures that included functional decline, survival, and respiratory decline. The company said it intends to present more detailed results at a future medical conference.
“As a physician who has treated people with ALS, I hoped with all my heart for a different outcome,” Douglas Kerr, M.D., Ph.D., director of neurodegeneration clinical research at Biogen Idec, said in a statement. “While these results were not what we expected, we hope these data will provide a foundation for future ALS research.”
EMPOWER was a randomized, double-blind, placebo-controlled trial that enrolled 943 people with ALS at 81 sites in 11 countries. Patients were randomized one-to-one to receive either dexpramipexole or placebo.
Eric Schmidt, an analyst with Cowen & Co., was reported last year by Bloomberg as estimating that dexpramipexole could generate as much as $1 billion annually for Biogen Idec. In a research note to investors, he said some 20 failed clinical studies examined ALS drug candidates.
To date just one drug remains approved for treatment of ALS, Sanofi’s Rilutek (riluzole), which only slows down the disease, offering modest improvement for patients. The drug has been estimated to generate between $40 million and $50 million in annual sales, though in 2010, FDA approved a first generic version of Rilutek from India’s Sun Pharmaceuticals.
On Dec. 19, a multiple-institution consortium of ALS researchers published results of 11 studies in Science Translational Medicine showing that transplantation of neural stem cells into the spinal cord of an ALS mouse model slowed disease onset and progression, improved its motor function, and significantly prolonged its survival.
And earlier last year, FDA granted its fast-track designation for Cytokinetics’ ALS drug candidate tirasemtiv, which showed some promise in a pair of Phase II trials—specifically in measures of disease progression and changes in functional status (ALSFRS-R) and the clinical assessment of pulmonary function and endurance known as MVV. However, dexpramipexole also enjoyed promising Phase II results, prompting Biogen Idec to press forward with EMPOWER.
Biogen Idec highlighted several initiatives it said demonstrated its commitment to further ALS research. The company recently launched a research collaboration with the HudsonAlpha Institute and Duke University aimed at learning more about the disease’s genetic causes, namely by sequencing the genomes of up to 1,000 people with ALS over the next five years.
The company also noted that it committed “significant” funds to the University of Massachusetts Medical School ALS Champion Fund, to support basic and clinical research into potential treatments for ALS and other neurodegenerative diseases. In addition, Biogen Idec joined several top-tier academic research centers to launch a research consortium committed to identifying new treatment approaches to the disease.