Browsing by Author "Baker, Brenda F."

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    Inotersen Treatment for Patients with Hereditary Transthyretin Amyloidosis
    (MMS, 2018-07) Benson, Merrill D.; Waddington-Cruz, Márcia; Berk, John L.; Polydefkis, Michael; Dyck, Peter J.; Wang, Annabel K.; Planté-Bordeneuve, Violaine; Barroso, Fabio A.; Merlini, Giampaolo; Obici, Laura; Scheinberg, Morton; Brannagan, Thomas H., III; Litchy, William J.; Whelan, Carol; Drachman, Brian M.; Adams, David; Heitner, Stephen B.; Conceição, Isabel; Schmidt, Hartmut H.; Vita, Giuseppe; Campistol, Josep M.; Gamez, Josep; Gorevic, Peter D.; Gane, Edward; Shah, Amil M.; Solomon, Scott D.; Monia, Brett P.; Hughes, Steven G.; Kwoh, Jesse; McEvoy, Bradley W.; Jung, Shiangtung W.; Baker, Brenda F.; Ackermann, Elizabeth J.; Gertz, Morie A.; Coelho, Teresa; Pathology and Laboratory Medicine, School of Medicine
    BACKGROUND Hereditary transthyretin amyloidosis is caused by pathogenic single-nucleotide variants in the gene encoding transthyretin (TTR) that induce transthyretin misfolding and systemic deposition of amyloid. Progressive amyloid accumulation leads to multiorgan dysfunction and death. Inotersen, a 2′-O-methoxyethyl–modified antisense oligonucleotide, inhibits hepatic production of transthyretin. METHODS We conducted an international, randomized, double-blind, placebo-controlled, 15-month, phase 3 trial of inotersen in adults with stage 1 (patient is ambulatory) or stage 2 (patient is ambulatory with assistance) hereditary transthyretin amyloidosis with polyneuropathy. Patients were randomly assigned, in a 2:1 ratio, to receive weekly subcutaneous injections of inotersen (300 mg) or placebo. The primary end points were the change in the modified Neuropathy Impairment Score+7 (mNIS+7; range, −22.3 to 346.3, with higher scores indicating poorer function; minimal clinically meaningful change, 2 points) and the change in the score on the patient-reported Norfolk Quality of Life–Diabetic Neuropathy (QOL-DN) questionnaire (range, −4 to 136, with higher scores indicating poorer quality of life). A decrease in scores indicated improvement. RESULTS A total of 172 patients (112 in the inotersen group and 60 in the placebo group) received at least one dose of a trial regimen, and 139 (81%) completed the intervention period. Both primary efficacy assessments favored inotersen: the difference in the least-squares mean change from baseline to week 66 between the two groups (inotersen minus placebo) was −19.7 points (95% confidence interval [CI], −26.4 to −13.0; P<0.001) for the mNIS+7 and −11.7 points (95% CI, −18.3 to −5.1; P<0.001) for the Norfolk QOL-DN score. These improvements were independent of disease stage, mutation type, or the presence of cardiomyopathy. There were five deaths in the inotersen group and none in the placebo group. The most frequent serious adverse events in the inotersen group were glomerulonephritis (in 3 patients [3%]) and thrombocytopenia (in 3 patients [3%]), with one death associated with one of the cases of grade 4 thrombocytopenia. Thereafter, all patients received enhanced monitoring. CONCLUSIONS Inotersen improved the course of neurologic disease and quality of life in patients with hereditary transthyretin amyloidosis. Thrombocytopenia and glomerulonephritis were managed with enhanced monitoring.
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    Ligand conjugated antisense oligonucleotide for the treatment of transthyretin amyloidosis: preclinical and phase 1 data
    (Wiley, 2021) Viney, Nicholas J.; Guo, Shuling; Tai, Li-Jung; Baker, Brenda F.; Aghajan, Mariam; Jung, Shiangtung W.; Yu, Rosie Z.; Booten, Sheri; Murray, Heather; Machemer, Todd; Burel, Sebastien; Murray, Sue; Buchele, Gustavo; Tsimikas, Sotirios; Schneider, Eugene; Geary, Richard S.; Benson, Merrill D.; Monia, Brett P.; Medicine, School of Medicine
    Aims: Amyloidogenic transthyretin (ATTR) amyloidosis is a fatal disease characterized by progressive cardiomyopathy and/or polyneuropathy. AKCEA-TTR-LRx (ION-682884) is a ligand-conjugated antisense drug designed for receptor-mediated uptake by hepatocytes, the primary source of circulating transthyretin (TTR). Enhanced delivery of the antisense pharmacophore is expected to increase drug potency and support lower, less frequent dosing in treatment. Methods and results: AKCEA-TTR-LRx demonstrated an approximate 50-fold and 30-fold increase in potency compared with the unconjugated antisense drug, inotersen, in human hepatocyte cell culture and mice expressing a mutated human genomic TTR sequence, respectively. This increase in potency was supported by a preferential distribution of AKCEA-TTR-LRx to liver hepatocytes in the transgenic hTTR mouse model. A randomized, placebo-controlled, phase 1 study was conducted to evaluate AKCEA-TTR-LRx in healthy volunteers (ClinicalTrials.gov: NCT03728634). Eligible participants were assigned to one of three multiple-dose cohorts (45, 60, and 90 mg) or a single-dose cohort (120 mg), and then randomized 10:2 (active : placebo) to receive a total of 4 SC doses (Day 1, 29, 57, and 85) in the multiple-dose cohorts or 1 SC dose in the single-dose cohort. The primary endpoint was safety and tolerability; pharmacokinetics and pharmacodynamics were secondary endpoints. All randomized participants completed treatment. No serious adverse events were reported. In the multiple-dose cohorts, AKCEA-TTR-LRx reduced TTR levels from baseline to 2 weeks after the last dose of 45, 60, or 90 mg by a mean (SD) of -85.7% (8.0), -90.5% (7.4), and -93.8% (3.4), compared with -5.9% (14.0) for pooled placebo (P < 0.001). A maximum mean (SD) reduction in TTR levels of -86.3% (6.5) from baseline was achieved after a single dose of 120 mg AKCEA-TTR-LRx . Conclusions: These findings suggest an improved safety and tolerability profile with the increase in potency achieved by productive receptor-mediated uptake of AKCEA-TTR-LRx by hepatocytes and supports further development of AKCEA-TTR-LRx for the treatment of ATTR polyneuropathy and cardiomyopathy.