Platelet reductions dent Ionis' Phase III FCS readout

Ionis Pharmaceuticals Inc. (NASDAQ:IONS) lost $4.52 to $50.18 after reporting results of the Phase III APPROACH trial of volanesorsen (IONIS-APOCIIIRx) to treat familial chylomicronemia syndrome, a disorder that leads to high triglyceride concentrations. Although the therapy met APPROACH's primary endpoint, Ionis revealed that five of 33 patients receiving the therapy discontinued treatment due to platelet declines.

Volanesorsen, an apolipoprotein C-III (APOCIII; APOC3) antisense inhibitor, reduced mean triglycerides from baseline after three months by 77% vs. an 18% increase for placebo (p<0.0001), meeting the study's primary endpoint. The company said the reductions were sustained over the trial’s 52-week treatment period. Among patients with baseline triglycerides ≥750 mg/dL, 50% of those receiving volanesorsen had triglyceride levels below 500 mg/dL after three months vs. none for placebo (p<0.003)...