NKX019, Intravenous Allogeneic Chimeric Antigen Receptor Natural Killer Cells (CAR NK), in Adults With Autoimmune Disease (Ntrust-1)

General Inclusion Criteria:

1. Age ≥18 and ≤65

2. Progression despite maximal tolerated doses of renin-angiotensin system (RAS)blockade agents

3. For participants taking chronic corticosteroids for management of the disease understudy, stable dose for ≥ 14 days before the screening visit with planned reductionto ≤ 5 mg prednisone by the time of LD start

4. Negative SARS-CoV-2 test

LN-specific Inclusion Criteria:

1. Score of 10 or more points on the American College of Rheumatology (ACR) 2019classification criteria for SLE

2. Active nephritis Class III, IV, and/or V using the 2018 International Society ofNephrology and Renal Pathology Society (ISN/RPS) criteria (Bajema 2018) as evidencedon kidney biopsy during screening or within 6 months before screening. Per NIHindices, subjects must have at least moderate activity score and no more thanmoderate chronicity index

3. Active renal disease as defined by urinary protein:creatinine ratio (UPCR) ≥ 1.5 g/gor proteinuria ≥1.5 g/day and ≤ 7 g/day

4. Positive antinuclear antibodies (ANA) ≥ 1:80 OR anti-dsDNA OR anti-Smith (anti-Sm)

5. Refractory LN defined as having received ≥ 2 prior therapies for LN

pMN-specific Inclusion Criteria:

1. Evidence of pMN by renal biopsy during screening or within 6 months before screening

2. Active renal disease at screening defined by UPCR ≥ 3.5 g/g or proteinuria ≥ 3.5g/day

3. Positive anti-PLA2R antibodies

4. Refractory or intolerant to either B cell-depleting agents and/or cyclophosphamideand/or calcineurin inhibitors defined as not achieving a complete remission after 180 days, or partial remission after 90 days

General Exclusion Criteria:

1. eGFR < 45 ml/min/1.73 m^2

2. Currently requiring renal dialysis or expected to require dialysis during the studyperiod

3. Previous solid organ or hematopoietic cell transplant or planned transplant withinstudy treatment period

4. Congenital or acquired immunodeficiency resulting in severe infection or thosereceiving chronic immunoglobulin replacement therapy

5. Liver disease or dysfunction, including cirrhosis and/or aspartate aminotransferase,alanine aminotransferase, or bilirubin ≥ 3 times the upper limit of normal

6. Pulmonary comorbidity including chronic obstructive pulmonary disease or asthmarequiring daily oral steroids, resting hypoxemia (<92% oxygen saturation via pulseoximetry) on room air, or significant smoking history (i.e. >10 pack/year)

7. White blood cell count < 3,000/mm^3; hemoglobin levels < 9 gm/dL absolute neutrophilcount < 2,000/mm^3; platelet count < 100,000/mm^3

8. Major cardiac disease, abnormalities, or interventions as defined by, but notlimited to:

9. Uncontrolled angina or unstable life-threatening arrhythmias

10. History of myocardial infarction within 12 weeks prior to the first dose ofNKX019

11. Any prior coronary artery bypass graft surgery

12. ≥ Class III New York Heart Association (NYHA) congestive heart failure (CHF),significantly decreased ejection fraction (EF ≤ 40%), or severe cardiacinsufficiency.

13. Prolongation of the QT interval corrected for heart rate (QTc) (Fridericia)interval of > 480 msec

14. Peripheral artery bypass graft surgery, pulmonary embolism, or other ≥ Grade 2thrombotic or embolic events within 12 weeks prior to the first dose of NKX019

15. Uncontrolled hypertension (systolic blood pressure > 160mmHg and diastolic > 90mmHg) despite therapy

16. Active bleeding disorders

17. Any overlapping autoimmune condition for which the condition itself or the treatmentof that condition may affect the study assessments or outcomes; conditions thatcould cause a secondary nephropathy; or kidney biopsy-confirmed significant renaldisease other than disease under study

18. Pregnancy, breast feeding or, if of childbearing potential, not using adequatecontraceptive precautions

19. Current infection requiring active systemic anti-infective therapy or recent acuteinfection requiring systemic therapy within 30 days of planned LD

20. History of positive HIV antibody or test positive at screening, Hepatitis B or Cpositive at screening, active tuberculosis (TB) or latent TB requiring suppressivetherapy

21. Malignancy within 5 years of screening, with the exception of basal and squamouscell carcinomas treated by complete excision. Subjects with cervical dysplasia thatis cervical intraepithelial neoplasia but have been treated with conization or loopelectrosurgical excision procedure and have had a normal repeat Papanicolaou testare allowed

22. Prior cellular therapy

23. Central nervous system (CNS) comorbidity or any autoimmune disease with CNSinvolvement within 90 days prior to the first dose of NKX019 as well as active CNSlupus within 1 year prior to screening

24. Any other acute or chronic medical or psychiatric condition, or known laboratoryabnormality that, in the Investigator's opinion, is expected to interfere or impactstudy participation

25. Prior immunosuppressive/immunomodulating therapies, including investigationalagents, within 14 days or 5 half-lives of the drug (whichever is shorter), prior toLD. Note: Prior antibody therapies not allowed within 90 days of LD

26. Currently taking or known need for any of the medications prohibited in the studyprotocol

27. Known hypersensitivity or contraindications to the study treatment including LD; orother components such as human serum albumin or dimethyl sulfoxide

LN-specific Exclusion Criteria:

1. Known antiphospholipid antibody syndrome (APS); or high-risk profile