Case Report: Inotersen reintroduction after thrombocytopenia in hereditary transthyretin amyloidosis: a case series
Year: 2026
Type: article
Study design: Case Report
Abstract: Background: ATTRv amyloidosis is a progressive multisystem disease caused by pathogenic variants in the transthyretin (TTR) gene. Inotersen is approved for the treatment of polyneuropathy in adults with hereditary transthyretin mediated amyloidosis, but thrombocytopenia is a clinically relevant adverse event that may require treatment interruption or discontinuation. Evidence guiding reintroduction of inotersen after thrombocytopenia is limited. Case Presentation: We retrospectively reviewed two men with genetically confirmed ATTRv treated at two centers in Argentina who developed treatment-emergent thrombocytopenia during inotersen therapy. Patient 1 was a 71-year-old man with late-onset mixed neurologic and cardiac ATTRv due to TTR p.Val50Met who developed grade 2 thrombocytopenia after 22 weeks of treatment, with a platelet nadir of 58 × 10^9/L. Patient 2 was a 52-year-old man with early-stage neuropathic ATTRv due to TTR p.Val50Met who developed grade 4 thrombocytopenia after 65 weeks, with platelet counts below 20 × 10^9/L, and had recurrent thrombocytopenia during an initial reintroduction attempt. Intervention and Outcomes: After platelet recovery and exclusion of alternative causes of thrombocytopenia, both patients underwent a structured 7-day stepwise short-term reintroduction protocol under close hematologic monitoring. Following protocol completion, inotersen was resumed at 284 mg every 2 weeks. During follow-up, neither patient developed recurrent severe thrombocytopenia, and both maintained biochemical evidence of transthyretin suppression. Conclusion: In this small case series, inotersen reintroduction after thrombocytopenia was feasible in two ATTRv patients when implemented with a structured stepwise protocol and close platelet monitoring, but these findings are hypothesis-generating and not generalizable. One reintroduction occurred outside prescribing recommendations for severe thrombocytopenia and should not be interpreted as a recommended strategy.
Source: Frontiers in Pharmacology
Institutions: Hospital San Juan de Dios, Hospital César Milstein
Language: English
Subfield: Internal Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7204495702