Primary Objective:

To evaluate the effect of dazodalibep on patient-reported symptoms of SS in participants with moderate-to-severe symptom state

Secondary Objectives:

1. To evaluate the effect of dazodalibep on patient-reported outcomes (PROs) in participants with SS.
2. To evaluate the effect of dazodalibep on measures of systemic activity, PROs, and salivary flow in participants with SS
3. To evaluate the safety and tolerability of multiple doses of dazodalibep in participants with SS

Acquired from Horizon in 2024.

Key Inclusion Criteria:

1. Diagnosed with SS by meeting the 2016 ACR/EULAR Classification Criteria

2. Have an ESSPRI score of ≥ 5 at screening.

3. Have an ESSDAI score of < 5 at screening.

4. Positive for either anti-Ro autoantibodies or RF, or both at screening (as per the definition of the standard central laboratory test).

5. Residual salivary gland function as defined by whole stimulated salivary flow > 0.1 mL/min.

6. Vaccinated against SARS-CoV-2 according to current local authority guidelines at least 2 weeks prior to screening unless participant refuses vaccination.

7. Meets all of the following tuberculosis (TB) criteria:

   1. No history of latent or active TB prior to screening, except for latent TB with documented completion of locally appropriate treatment.
   2. No signs or symptoms suggestive of active TB from medical history or physical examination.
   3. No recent (≤ 12 weeks of screening) close contact with a person with active TB (close contact is defined as ≥ 4 hours/week OR living in the same household OR in a house where a person with active TB is a frequent visitor).
   4. Negative Interferon Gamma Release Assay (IGRA) test result for TB at screen unless previously treated as per Inclusion Criterion. Participants with an indeterminate test result can repeat the test, but if the repeat test is also indeterminate, they are excluded.
   5. A chest radiograph (obtained during the screening period or any time within 12 weeks prior to screening) with no evidence of current active TB or other infection, or prior TB, malignancy, or clinically significant abnormalities suggesting an active process (unless due to SS).

Key Exclusion Criteria:

1. Individuals with medical history of confirmed deep venous thrombosis, pulmonary embolism, or arterial thromboembolism within 2 years of screening.

2. History or presence of concomitant polymyositis or dermatomyositis or systemic sclerosis.

3. Active malignancy or history of malignancy within the last 5 years, except as follows:

   1. In situ carcinoma of the cervix treated with apparent success with curative therapy > 12 months prior to screening; OR
   2. Cutaneous basal cell carcinoma following presumed curative therapy.

4. Individuals who are pregnant or lactating or planning to become pregnant during the study.

5. Individuals with known history of severe allergy or reaction to any component of the IP formulation or to any other biologic therapy.

6. Individuals with any severe cardiovascular, respiratory, endocrine, gastrointestinal, hematological, neurological, psychiatric, or systemic disorder or any other condition that, in the opinion of the Investigator, would place the individual at unacceptable risk of complications, interfere with evaluation of the IP, or confound the interpretation of participant safety or study results.

7. Individuals who have a positive test for, or have been treated for, hepatitis B, hepatitis c or HIV infection.

8. Individuals with a positive test for SARS-CoV-2 on the day of randomization or symptoms suggestive of SARS-CoV-2 at randomization or significant exposure to coronavirus disease 2019 (COVID-19) within 10 calendar days prior to randomization.

9. Individuals with:

   1. A history of more than one episode of herpes zoster and/or opportunistic infections in the last 12 months, with the exception of non-invasive herpes simplex at any site, oral candidiasis, vaginal candidiasis, or cutaneous fungal infections, which are permitted within the prior 12 months unless of unusual severity.
   2. Active infection requiring systemic treatment at the time of screening or through randomization, or history of more than 2 infections requiring IV antibiotics within 12 months prior to screening.

De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.

Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.

Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest, statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors. If not approved, a Data Sharing Independent Review Panel will arbitrate and make the final decision. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.