CD4 and neutropenia: Consensus guidelines advocate for acyclovir/valacyclovir to prevent HSC/VZV reactivation, trimethoprim-sulfamethoxazole for Pneumocystis jirovecii (in CAR-T cells: recommended for 12-18 months post-infusion, at least until CD4 count exceeds >200/μL; in BiTEs: during treatment and up to 1 month post-treatment discontinuation), and antifungal prophylaxis with fluconazole during periods of prolonged severe neutropenia or extended steroid therapy (131, 134).