TNFRSF17 and Miyoshi myopathy: The first anti-BCMA BsAb entering clinical practice is teclistamab, due to the promising results of the MajesTEC-1 phase 1/2 trial (NCT03145181, NCT04557098): at the dose of 1.5 mg/kg once a week, the ORR was 63% (≥VGPR: 59%) and the median PFS was 11 months for heavily pretreated MM patients (triple-refractory: 78%, penta-refractory: 30%), without unexpected adverse events (CRS, mostly of grade 1–2: 72%; hematological toxicity: 71%, grade ≥ 3: 65%; infections: 76%, grade ≥ 3: 45%; ICANS: 5%, grade ≥ 3: <1%) [69,70,71,72].