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The patient responded well to this therapy, with excellent symptomatic and quality of life improvements as well as a reduction in bleeding manifestations. This case highlights the value in considering daratumumab treatment when AL amyloidosis is complicated by FX deficiency.<\/jats:p>","DOI":"10.1136\/bcr-2020-240631","type":"journal-article","created":{"date-parts":[[2021,4,7]],"date-time":"2021-04-07T14:05:11Z","timestamp":1617804311000},"page":"e240631","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":2,"title":["Response of factor X deficiency to darutumumab in the treatment of AL amyloidosis: a novel finding"],"prefix":"10.1136","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4088-3795","authenticated-orcid":false,"given":"Ethan","family":"Mar","sequence":"first","affiliation":[{"name":"Department of Haematology, Metro South Hospital and Health Service, Woolloongabba, Queensland, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kerry","family":"Taylor","sequence":"additional","affiliation":[{"name":"Icon Cancer Care, Mater Medical Centre, Brisbane, Queensland, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peter","family":"Mollee","sequence":"additional","affiliation":[{"name":"Department of Haematology, Metro South Hospital and Health Service, Woolloongabba, Queensland, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2021,4,7]]},"reference":[{"key":"2025082708201374000_14.4.e240631.1","unstructured":"Weber N , Mollee P . Management of systemic al amyloidosis. Medical scientific Advisory group (MSAG) to the myeloma Foundation of Australia. 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