Biogen/Ionis tofersen slows decline in certain functions in ALS patients in new data
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Biogen (NASDAQ:BIIB) said that 12-month data for tofersen showed that earlier initiation of the drug slowed decline in clinical, and respiratory function, muscle strength, and quality of life in patients with superoxide dismutase 1 (SOD1) amyotrophic lateral sclerosis (ALS).
Tofersen was licensed by Biogen from Ionis (NASDAQ:IONS) in 2018. The drug had failed to meet the main goal of a phase 3 trial, called VALOR, data from which is part of this 12-month data.
Biogen said in a June 3 release that the results are based on new integrated data from the VALOR study and its open-label extension (OLE) study.
The data showed that earlier initiation of tofersen compared to delayed initiation (six months later in the OLE study) slowed the declines.
ALS is a progressive nervous system disorder affecting nerve cells in the brain and spinal cord, leading to loss of muscle control. SOD1 ALS is caused due to mutations in the SOD1 gene.
Biogen said that VALOR had not met its main goal but trends of reduced disease progression across several secondary and exploratory endpoints were seen.
Biogen noted that at the time of the analysis, because the majority of people survived without permanent ventilation (PV), the median time to death or PV could not be estimated. But, early survival data suggested a lower risk of death or PV and death with an early start of tofersen.
The company said most common adverse events (AEs) both in VALOR and OLE were mild to moderate in severity.
Serious AEs were reported in 36.5% of people who received tofersen in VALOR and/or the OLE; 17.3% of people discontinued treatment due to an AE.
Biogen (BIIB) noted that 14 deaths were reported in tofersen-treated people, all of which were determined not to be related to tofersen.