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Sporadic late onset nemaline myopathy (SLONM) is a rare, autoimmune myopathy often associated with a monoclonal gammopathy of uncertain significance (MGUS) or multiple myeloma. Clinical and histological features can mimic other myopathies, including mitochondrial myopathy, facioscapulohumeral dystrophy, necrotising autoimmune myositis among others. The diagnostic journey is often prolonged, and although case series and case reports suggest a treatment response to immunotherapy, chemotherapy and autologous stem cell transplantation (ASCT), the relative utility of each of these is poorly understood. The largest case series to date at The Mayo Clinic reported only 28 cases, with 40% being treated with immunosuppression, 15% with ASCT and 8% with chemotherapy.We report a case, the diagnostic process of which we have previously reported,1 of a 73-year-old lady with myeloma-associated SLONM who has had a significant response to VRd lite chemotherapy directed at her plasma cell clone. Over 2 years of therapy, she regained significant function – in particular, a profound head drop resolved, her forced vital capacity increased 20%, nocturnal hypoventilation resolved, and appendicular strength improved to a MRC90 of 80 (nadir of 62).Thus, we present this as an example of directed haematologic therapy resulting in substantial clinical improvement for this rare disease, without the need for ASCT (and associated mortality/morbidity).Reference Clarke A, Winkel A. 2835 Spontaneous late onset nemaline myopathy (SLONM) and its diagnostic challenge. BMJ Specialist Journals 2023.