A Randomized, Double-blind 2-arm, Followed by an Open-label 1-arm, NEPTUNUS Extension Study to Assess the Long-term Safety and Efficacy of Ianalumab in Patients With Sjogrens Syndrome.

Inclusion Criteria: 1. Signed informed consent prior to participation in the extension study. 2. Participants must have participated in either one of the two NEPTUNUS core studies, CVAY736A2301 or CVAY736A2302, and must have completed the entire treatment up to Week 48 without treatment discontinuation in core NEPTUNUS studies. 3. In the judgement of the Investigator, participants must be expected to clinically benefit from continued ianalumab therapy. Exclusion Criteria: 1. Use of therapies excluded by the NEPTUNUS-1 and NEPTUNUS-2 study protocols (see NEPTUNUS studies protocols exclusion criteria in Section 5.2 for details). 2. Plans for administration of live vaccines during the study period. 3. Pregnant or nursing (breastfeeding) women, where pregnancy is defined as the state of a female after conception and until the termination of gestation, confirmed by a positive human Chorionic Gonadotropin (hCG) laboratory test. 4. Women of child-bearing potential (WOCBP), defined as all women physiologically capable of becoming pregnant, from menarche until becoming post-menopausal, unless they have had surgical bilateral oophorectomy (with or without hysterectomy), total hysterectomy or bilateral salpingectomy at least six weeks before taking study treatment. In the case of oophorectomy alone, the reproductive status of the woman needs to have been confirmed by follow-up hormone level assessment. Women are considered post-menopausal if they have had 12 months of natural (spontaneous) amenorrhea with an appropriate clinical profile (e.g., hormonal profile confirming menopause and/or age-appropriate history of vasomotor symptoms). WOCBP are excluded unless they are using highly effective methods of contraception (failure rate \< 1% per year) while taking study treatment during dosing and for 6 months after stopping of investigational drug. Highly effective contraception methods include: * Total abstinence (when this is in line with the preferred and usual lifestyle of the participant. Periodic abstinence (e.g., calendar, ovulation, symptothermal, post- ovulation methods) and withdrawal are not acceptable methods of contraception. * Bilateral tubal occlusion or bilateral tubal ligation (at least six weeks before taking study treatment). * Sterilization (vasectomy) of male partner (s) of the female participant at least 6 months prior to screening provided partner(s) has(have) received medical confirmation of surgical process. * Use of hormonal contraception methods: * Combined (estrogen and progestogen-containing) hormonal contraception associated with inhibition of ovulation; oral, intravaginal or transdermal. * Progestogen-only hormonal contraception associated with inhibition of ovulation: oral, injectable or implantable. * Intrauterine device (IUD) or intrauterine hormone-releasing system (IUS) In case of use of oral contraception women should have been stable on the same pill for a minimum of 3 months before taking study treatment. Contraception should be used in accordance with locally approved prescribing information of concomitant medications administered. If local regulations are more stringent than the contraception methods listed above, local regulations apply and will be described in the informed consent form (ICF). 5. United States (and other countries, if male contraception is locally required): Sexually active males, unless they agree to use barrier protection during intercourse with a woman of child-bearing potential, while taking study treatment. As condom use alone has a reported failure rate exceeding 1% per year, it is recommended that female partners of male study participants use a second method of birth control. Although ianalumab is not teratogenic and/or genotoxic, and not transferred to semen, male contraception is required, as requested by FDA. Globally, for all sexually active males, contraception should be used in accordance with the locally approved prescribing information of concomitant medications administered.