∙ For rheumatoid arthritis:

• Moderate-to-severely active RA as defined by the presence of ≥4 swollen joints (based on 28 joint count) and ≥4 tender joints (based on 28 joint count) at Screening and Day 1.

• Documentation of ≥1 of the following:

‣ Positive test results for rheumatoid factor or anti-citrullinated peptide antibodies at Screening, OR

⁃ Previous radiographs with bony erosions in hands or feet consistent with RA

• Inadequate response (defined as signs and symptoms of persistently active disease, loss of response, or intolerance) to one of the following:

‣ ≥1 csDMARD treatment; OR

⁃ 1 bDMARD or 1 tsDMARD treatment (a total of 2 bDMARDs and/or tsDMARDs is exclusionary)

∙ For axial spondyloarthritis:

• Moderate-to-severely active axSpA defined by BOTH of the following at Screening AND Day 1:

‣ BASDAI ≥4, AND

⁃ Back pain ≥4 (from BASDAI Item 2)

• hsCRP greater than the ULN per the central laboratory at Screening - Inadequate response (defined as signs and symptoms of persistently active disease, loss of response, or intolerance) to one of the following:

‣ 2 different NSAIDs given at the maximum tolerated dose for ≥4 weeks or intolerant to or has a contraindication to NSAID therapy; OR

⁃ 1 bDMARD (anti-TNF or anti-IL-17) or 1 tsDMARD treatment at an approved dose for ≥12 weeks (a total of 2 bDMARDs and/or tsDMARDs is exclusionary)

∙ For psoriatic arthritis:

• Day 1 TJC ≥3 out of 68 and SJC ≥3 out of 66 (dactylitis counts as 1 joint each)

• ≥1 active plaque psoriasis lesion and/or a documented history of psoriasis

• In adequate response (defined as signs and symptoms of persistently active disease, loss of response, or intolerance) to one of the following:

‣ ≥1 NSAID treatment; AND

⁃ ≥1 csDMARD treatment; OR

⁃ 1 bDMARD or 1 tsDMARD treatment (a total of 2 bDMARDs and/or tsDMARDs is exclusionary)