Patisiran Safe and Effective for Hereditary Transthyretin-Mediated Amyloidosis

Amyloidosis – diagnosis written on a white piece of paper. Syringe and vaccine with drugs.
A team of researchers sought to describe efficacy and safety analyses of the Global Open-Label Extension (OLE) study of patisiran for hereditary transthyretin-mediated amyloidosis with polyneuropathy.

The following article is part of conference coverage from the American Academy of Neurology (AAN) 2021 Virtual Annual Meeting. Neurology Advisor’s staff will be reporting breaking news associated with research conducted by leading experts in neurology. Check back for the latest news from the AAN 2021 Virtual Annual Meeting.

Patisiran, a treatment for polyneuropathy in patients with hereditary transthyretin-mediated (hATTR) amyloidosis, continued to show efficacy in this population at 24 months of treatment, according to study results to be presented at the American Academy of Neurology (AAN) 2021 Virtual Annual Meeting from April 17 to 22, 2021.

Study researchers sought to determine efficacy and safety of the ongoing Global Open-Label Extension (OLE) study of patisiran in patients with this progressive and life-threatening disease that can affect multiple organ systems. Phase 3 APOLLO and Phase 2 OLE studies of the treatment have demonstrated its efficacy and safety.

The research team conducted an international OLE study ( identifier NCT02510261), which included eligible patients who had completed parent studies, including APOLLO study patients who were randomly assigned to receive placebo (n=49) or patisiran (n=137) and Phase 2 OLE study patients (n=25), who received treatment.

When study researchers conducted 24-month assessments for 178 of the 211 patients as of October 7, 2019, the safety profile of patisiran had remained consistent with that of previous studies. Findings indicated durable improvement in the OLE study participants for modified neuropathy impairment score (mNIS)+7 (mean change [standard error of the mean (SEM)]) in the APOLLO/patisiran (-4.9 [2.1]) and Phase 2 OLE (-5.9 [2.1]) groups compared with parent study baselines.

Norfolk Quality of Life-Diabetic Neuropathy (QOL-DN) continued to show durable improvement in APOLLO/patisiran patients (-2.4 [2.4]) following an additional 24 months of treatment.

In the Global OLE, APOLLO/placebo patients exhibited halting of disease progression and improvement in quality of life (QOL) compared with Global OLE baseline following 24 months of patisiran (mNIS+7: +0.1 [3.3], Norfolk QOL-DN: -4.1 [3.3]), although they progressed compared with APOLLO baseline (mNIS+7: +26.3 [5.0], Norfolk QOL-DN: +15.8 [4.5]) given progression while on placebo in APOLLO.

Although patients in the placebo arm of the trial exhibited “marked progression” during APOLLO, after 24 months of using patisiran, patients who had previously been untreated continued to “exhibit halting of disease progression” and improvement in QOL

“Patisiran continues to demonstrate a positive benefit:risk profile,” the study researchers concluded.


Adams D, Gonzalez-Duarte A, Mauricio E, et al. Global open-label extension: 24-month data in patients with hATTR amyloidosis. Presented at: the American Academy of Neurology 2021 Virtual Annual Meeting; April 17 to 22, 2021. Abstract S32.001.