REACT-01: Reversing Autoimmunity Through Cell Therapy

Inclusion Criteria:

* Male and female subjects aged between 2-30 years old. The first 3 subjects will be aged ≥ 17. The FDA will review safety data to determine if the age can be lowered first to ≥ 12 then, following the treatment of 3 further subjects aged 12-17, to ≥ 2
* Serologically active Systemic Lupus Erythematosus that is refractory to treatment
* Able to tolerate apheresis or already has an apheresis product available for use in manufacturing.
* ≥ 24 weeks post last Rituximab or related B cell depleting therapy
* ≥ 12 weeks post last Belimumab / Anifrolumab therapy
* ≥ 4 weeks post last calcineurin inhibitor treatment
* For subjects receiving non-calcineurin immunosuppressive therapy, on a stable dose for ≥ 8 weeks before enrollment
* For subjects receiving corticosteroid therapy, on a stable dose for ≥ 2 weeks before enrollment
* Adequate organ function
* Adequate laboratory values
* Subjects of childbearing or child-fathering potential must agree to use highly effective contraception from consent through 12 months following infusion of investigational product on trial
* Subjects must be willing to remain within 1 hour's drive of Seattle Children's Hospital for 4 weeks following CAR T cell infusion.
* Subject and/or legally authorized representative has signed the informed consent form for this study

Exclusion Criteria:

* History or presence of active CNS lupus or other CNS disease
* Kidney dysfunction requiring renal replacement therapy
* Pregnant or breastfeeding
* Insufficient pulmonary reserve including history of COPD, \>10 pack year smoking history or SLE lung disease with hypoxia at rest with oxygen saturation ≤92% on room air
* Unable to tolerate repletion with any formulation of IgG.
* Active or prior malignancy, unless the malignancy was treated and there is no evidence of recurrent disease \<5 years from enrollment.
* Prior solid organ transplantation.
* Presence of an active severe infection
* Presence of any condition that, in the opinion of the investigator, would prohibit the subject from undergoing treatment under this protocol