Study of Power Doppler Ultrasound (PDUS) to Measure Response of Secukinumab Treatment in Patients With Active Psoriatic Arthritis (PsA)

This is a 52-week, multicenter, international study consisting of a 2 to 4-week Screening
period, a 12-week randomized, placebo-controlled double-blind treatment period (Period 1), a
12-week open-label treatment period (Period 2) and a 6-month open-label extension period
(Period 3).

Treatment Period 1 is a 12-week placebo-controlled, randomized period primarily designed to
demonstrate the early and optimal efficacy of secukinumab vs placebo on joint synovitis using
PDUS via the GLOESS and global entheseal score after 12 weeks of treatment.

The main aim of Period 2 is to assess the maintenance or increased magnitude of treatment
response on joint synovitis for patients from the original secukinumab groups and to assess
the time course of response with secukinumab on joint synovitis in the original placebo group
switched to secukinumab from Week 12.

The main aim of Period 3 (extension period) is to allow patients who respond to secukinumab
to extend study treatment up to Week 52 or until commercial drug becomes available, whichever
occurs sooner.

Inclusion Criteria:

1. Patient must be able to understand and communicate with the Investigator and comply
with the requirements of the study and must provide written, signed and dated informed
consent before any study assessment is performed.

2. Male or female patients at least 18 years of age.

3. Diagnosis of PsA as per CASPAR with active PsA for at least 6 months and a TJC ≥ 3 of
78 and SJC ≥ 3 of 76 at Baseline.

4. Patients must have a total synovitis PDUS score ≥ 2 and inflammation related to PD
signal ≥ 1 for at least 2 (affected joints as observed via PDUS) of 48 joints at the
Screening visit and at the Baseline visit (before infusion).

5. At least 1 clinically-involved enthesitis site at Screening and at the Baseline visit
(before infusion) defined by SPARCC index different from 0.

Exclusion Criteria:

1. Chest X-ray or chest MRI with evidence of ongoing infectious or malignant process
obtained within 3 months prior to Screening and evaluated by a qualified physician.

2. Previous exposure to secukinumab or other biologic drug directly targeting IL-17 or
IL-17 receptor.

3. Any change in the dose of oral corticosteroids in the last 4 weeks prior to the
Baseline visit or use of i.v. intramuscular or intra-articular corticosteroid during
the last 4 weeks prior to the enrollment visit.

4. Patients who have previously been treated with TNFα inhibitors (investigational or
approved).

5. History of hypersensitivity to the study drug or its excipients or to drugs of similar
classes.

6. Previous treatment with any cell-depleting therapies including but not limited to anti
CD20 investigational agents (e.g. CAMPATH, anti-CD4, anti-CD5, anti-CD3, anti CD19).

7. Prohibited psoriasis treatments/medications with topical corticosteroids in the last 4
weeks prior to randomization.

8. Pregnant or nursing (lactating) women.