The TSPAN33 aptamer’s unique specificity for activated B cells endows this conjugate with three distinct therapeutic advantages: (i) Enhanced target engagement – The aptamer-mediated site-specific delivery of anti-CD 20 antibodies improves therapeutic precision by selectively eliminating aberrant B cells in HT patients while sparing their healthy counterparts, thereby circumventing pan-B-cell depletion. Here, TSPAN33 is linked to hematocrit.