A Phase 1 Trial to Evaluate the Safety, Tolerability, Pharmacodynamics, Pharmacokinetics, and Immunogenicity of VIS171 in Participants With Autoimmune Disease(s)

Inclusion Criteria:

1. Estimated glomerular filtration rate (eGFR) >30 milliliters/minute/1.73 squaremeters (mL/min/1.73 m^2) at the screening visit. For SLE participants:

2. Participant has a confirmed diagnosis of SLE according to European League AgainstRheumatism/American College of Rheumatology SLE classification criteria ≥ 24 weeksprior to signing the informed consent form (ICF). For AA participants:

3. Current scalp involvement between 25% and 95%, inclusive (Severity of Alopecia Tool [SALT] score between 25 and 95, inclusive), at screening.

4. Current episode of AA is of duration > 24 weeks (without evidence of spontaneousterminal hair regrowth at the time of screening and first treatment, i.e., no morethan 10% regrowth), but ≤ 5 years from onset of current episode of severe scalp hairloss. For FSGS participants:

5. Prior biopsy (no time limit) showing histologic minimal change disease (MCD), FSGS,or MCD/FSGS spectrum.

6. History of at least one prior episode of nephrotic syndrome, defined as 24-hoururine protein > 3.5 grams per day (g/day) and serum albumin < 3.5 grams perdeciliter (g/dL).

7. History of steroid responsive nephrotic syndrome, including participants whoachieved complete remission, partial remission, had a course of steroid dependentnephrotic syndrome or relapsing nephrotic syndrome (all defined as per the managingphysician at the time of the episode).

Exclusion Criteria:

1. Receipt of high-dose corticosteroid therapy within 4 weeks prior to screening aseither (a) intravenous (IV) pulse corticosteroid therapy or (b) daily oralcorticosteroid therapy of ≥ 1 milligrams per kilogram (mg/kg) or up to 40 milligramsper day (mg/day) prednisone (or equivalent).

2. Receipt of blood products within 6 months prior to screening.

3. Previous exposure to VIS171 or any other drug targeting interleukins (IL)-2 or theIL-2 receptor or T regulatory cells.

4. History of or current diagnosis of catastrophic or severe anti-phospholipid syndrome (APS) within 1 year prior to signing ICF. SLE participants with APS adequatelycontrolled by anticoagulant are eligible. SLE participants who are found to betriple positive for anti-phospholipid antibodies at screening (without clinical APS)will be excluded unless they are on stable anti-thrombotic therapy.

5. Known primary immunodeficiency disorder.

6. Participant has a history of Class V lupus nephritis.

7. Receipt of anifrolumab, tumor necrosis factor-alpha monoclonal antibodies ([TNF]-αmAb), immunoglobulins (IV/SC) plasmapheresis, or any other immunosuppressants (calcineurin inhibitors, Janus kinase [JAK] inhibitors or other kinase inhibitors),other than hydroxychloroquine, mycophenolic acid (MPA)/mycophenolate mofetil (MMF)and corticosteroids, within 6 months prior to screening.

8. Participant has concomitant hair loss of another form, including but not limited totraction alopecia, central centrifugal cicatricial alopecia, lichen planopilaris,frontal fibrosing alopecia, or androgenetic alopecia.

9. Participant has received (1) Within 12 weeks prior to Day 1: Systemic therapies (oral or injection), such as corticosteroids, JAK inhibitors, methotrexate,calcineurin inhibitors, oral minoxidil, low-dose IL-2 and topical immunotherapiessuch as psoralen plus UVA (PUVA) , diphenylcyclopropenone (DPCP),dinitrochlorobenzene (DNCB), intralesional steroids or (2) Within 4 weeks prior toDay 1: Other topical therapies, such as topical minoxidil, clobetasol etc. Thesetherapies will also not be allowed during this trial.

10. Steroid resistant nephrotic syndrome defined as absence of history of at least 1episode of complete or partial remission following at least 12 weeks of full dosecorticosteroid therapy.

11. Receipt of anifrolumab, TNF-α mAb, immunoglobulins (IV/SC) plasmapheresis, or anyother immunosuppressants (JAK inhibitors or other kinase inhibitors).

Note: Other protocol-specified Inclusion/Exclusion criteria may apply.