Cardiac Subgroup Results from Phase 2 OLE Study of Patisiran, in Development for hATTR Amyloidosis

We reported final 24-month results from the subgroup of hereditary ATTR (hATTR) amyloidosis patients with cardiac involvement in the Phase 2 open-label extension (OLE) study of patisiran at the European Society of Cardiology Heart Failure (ESC-HF) Congress in Paris, France.

Results from the cardiac subgroup (N=11) of the Phase 2 OLE study showed a mean decrease in the modified neuropathy impairment score (mNIS+7) of 10.0 points at 24 months, which is comparable to the mean decrease in mNIS+7 of 7.0 observed in the overall study population (N=26). Patisiran also demonstrated a similar effect on quality of life, nutritional status, functional status, and patient reported autonomic neuropathy symptoms in the cardiac subgroup as in the overall study population. Further, patients showed stability in their cardiac biomarkers, echocardiographic measures, and 10-meter-walk speed over the 24-month period.

Patisiran administration was found to be generally well tolerated in hATTR amyloidosis patients with cardiac involvement, exhibiting a comparable safety profile to that observed in the overall study population. Three patients experienced serious adverse events (SAEs), all of which were unrelated to study drug.

hATTR amyloidosis is a spectrum disease where many patients have a mixed phenotype with aspects of both polyneuropathy and cardiomyopathy. We believe patisiran has the potential to become an important treatment option for patients living with this debilitating disease.