BHB & CAR-T for Lymphomas

Inclusion Criteria: * Age of 18 years or older * History of pathologically-confirmed large B-cell lymphoma (LBCL) * Planned treatment with a commercially available anti-CD19 CAR-T product (Yescarta or Kymriah) * Eligible for and with adequate organ function (investigator discretion) and performance status (ECOG PS 2 or less) for standard of care, anti-CD19 CAR-T * Not enrolled on a clinical trial of bridging therapy prior to CAR-T * Patients must have a PET/CT scan (preferred), diagnostic CT scan, or MRI with at least one bi-dimensionally measurable lesion (≥ 1.5 cm for nodal lesions or ≥ 1cm for extra- nodal lesions in largest dimension by low-dose computerized tomography \[CT\] scan with FDG-uptake ≥ liver) documented prior to leukapheresis for CAR-T manufacturing * Resolution of toxicities from prior therapy to a grade that does not contraindicate trial participation in the opinion of the investigator * Can provide informed consent * Willing to comply with all study procedures and available for the duration of the study Exclusion Criteria: * Subject is pregnant or breast feeding * History of allergy to energy drinks * History of inflammatory bowel disease * History of type 1 diabetes mellitus or requirement for insulin * History of chronic kidney disease with an eGFR \< 30 mL/min/1.73m2 * Additional second primary malignancy for which the subject is receiving active therapy or that will impede the ability of the investigator to assess lymphoma response