Early Data on Long-term Impact of Inotersen on Quality-of-Life in Patients with Hereditary Transthyretin Amyloidosis Polyneuropathy: Open-Label Extension of NEURO-TTR.

Patients with hereditary transthyretin amyloidosis associated with polyneuropathy (ATTRv-PN) experience deterioration in health-related quality of life (HRQOL) as the disease progresses. Findings from the randomized placebo-controlled phase III NEURO-TTR study showed treatment benefit of inotersen, an antisense oligonucleotide, for preserving or improving HRQOL after 65 weeks of treatment. The current analysis examines longitudinal trends in specific aspects of HRQOL, including polyneuropathy symptoms, daily activities, and physical, role, and social functioning in patients with ATTRv-PN receiving long-term treatment in a follow-up open-label extension (OLE) study. One-hundred thirty-five patients with ATTRv-PN were enrolled in an ongoing 5-year OLE study following completion of NEURO-TTR. Eighty-five patients received continuous weekly treatment with inotersen in both studies (inotersen-inotersen group), while 50 patients switched from placebo to inotersen at OLE study baseline (placebo-inotersen group). Descriptive analyses of changes in domain scores and item responses through week 104 of the OLE study were conducted for measures of neuropathy-related and generic HRQOL: Norfolk QOL-Diabetic Neuropathy (DN) questionnaire and SF-36v2® Health Survey (SF-36v2), respectively. For both inotersen-inotersen and placebo-inotersen groups, all Norfolk QOL-DN and most SF-36v2 domain scores remained stable from OLE baseline through week 104. Differences in HRQOL between the two groups at OLE baseline were sustained through week 104. Analysis of item responses from NEURO-TTR baseline to OLE study week 104 (170 weeks) for the inotersen-inotersen group found no notable increases in the proportion of patients reporting substantial impairments across a wide variety of symptoms, daily activities, and functioning. Long-term treatment with inotersen preserved HRQOL for patients with ATTRv-PN for periods of up to 3 years. The gap in HRQOL between those who had previously received inotersen or placebo in NEURO-TTR did not close by week 104 of the OLE phase, indicating the importance of early treatment for maintaining HRQOL in these patients. ClinicalTrials.gov Identifiers NCT01737398 for NEURO-TTR study; NCT02175004 for OLE study Hereditary transthyretin amyloidosis with polyneuropathy is a rare disease that causes damage to nerves in the limbs, leading to pain, numbness, loss of sensitivity, and muscle weakness, with eventual loss of the ability to walk (i.e., patients require a wheelchair or are bedridden). As the disease progresses, patients’ quality of life, including their ability to engage in everyday activities, socialize with others, work, and live independently, continually worsens. In a recent clinical trial (the NEURO-TTR study), patients with this disease randomized to receive the drug inotersen for 66 weeks maintained their quality of life, while patients randomized to receive a placebo showed continued worsening. All patients completing the NEURO-TTR study could participate in an extension study during which all patients knowingly received inotersen for up to 5 years. We examined quality of life in patients through the first 2 years of this extension study. For all patients, regardless of previous treatment (inotersen or placebo), most aspects of quality of life did not change throughout the 2-year extension study, showing that inotersen can preserve quality of life of these patients for up to 2–3 years. However, while quality of life in patients who had received placebo in the NEURO-TTR study did not get worse during the extension study, it also did not improve to match that of patients who received inotersen during the NEURO-TTR study. This finding shows the importance of treating these patients with inotersen as early as possible to preserve their quality of life before it substantially deteriorates.