Study Evaluating Efficacy and Safety of Octagam 10% in Patients With Dermatomyositis (Idiopathic Inflammatory Myopathy)

Inclusion Criteria:

1. Subjects with diagnosis of definite or probable DM according to the Bohan and Peter
criteria.

2. Subjects under treatment with corticosteroids and/or maximally 2 immune-suppressants
and being on stable therapy for at least 4 weeks.

3. Subjects with active disease, assessed and agreed upon by an independent adjudication
committee.

4. Manual Muscle Testing-8 (MMT-8) score <142, with at least 2 other abnormal Core Set
Measures (CSM) (Visual Analogue Scale [VAS] of patient global activity ≥2 cm,
physician's global disease activity ≥2 cm, extra-muscular activity ≥2 cm; at least one
muscle enzyme >1.5 times upper limit of normal, Health Assessment Questionnaire
≥0.25).

5. Males or females ≥ 18 to < 80 years of age.

6. Voluntarily given, fully informed written consent obtained from subject before any
study-related procedures are conducted.

7. Subject must be capable to understand and comply with the relevant aspects of the
study protocol.

Exclusion Criteria:

1. Cancer-associated myositis, defined as the diagnosis of myositis within 2 years of the
diagnosis of cancer (except basal or squamous cell skin cancer or carcinoma in situ of
the cervix that has been excised and cured and at least 5 years have passed since
excision).

2. Evidence of active malignant disease or malignancies diagnosed within the previous 5
years (including hematological malignancies and solid tumors) or breast cancer
diagnosed within the previous 10 years.

3. Subjects with overlap myositis (except for overlap with Sjögren's syndrome),
connective tissue disease associated DM, inclusion body myositis, polymyositis or
drug-induced myopathy.

4. Subjects with immune-mediated necrotizing myopathy with absence of typical DM rash.

5. Subjects with generalized, severe musculoskeletal conditions other than DM that
prevent a sufficient assessment of the subject by the physician.

6. Subjects who have received IgG treatment within the last 6 months before enrolment.

7. Subjects who received blood or plasma-derived products (other than IgG) or plasma
exchange within the last 3 months before enrolment.

8. Subjects starting or planning to start a physical therapy-directed exercise regimen
during the trial.

9. Cardiac insufficiency (New York Heart Association III/IV), cardiomyopathy, significant
cardiac dysrhythmia requiring treatment, unstable or advanced ischemic heart disease.

10. Severe liver disease, E.g. hepatitis or cirrhosis.

11. Severe kidney disease (creatinine 1.5 times above the upper limit of normal).

12. Known hepatitis B, hepatitis C or HIV infection.

13. Subjects with a history of deep vein thrombosis within the last year prior to study
enrollment or pulmonary embolism ever.

14. Body mass index ≥40 kg/m2.

15. Medical conditions whose symptoms and effects could alter protein catabolism and/or
IgG utilization (e.g. protein-losing enteropathies, nephrotic syndrome).

16. Known IgA deficiency with antibodies to IgA.

17. History of hypersensitivity, anaphylaxis or severe systemic response to
immuno-globulin, blood or plasma derived products or any component of Octagam 10%.

18. Known blood hyperviscosity, or other hypercoagulable states.

19. Subjects with a history of drug abuse within the past 5 years prior to study
enrollment.

20. Subjects unable or unwilling to understand or comply with the study protocol.

21. Participating in another interventional clinical study with investigational treatment
within 3 months prior to study enrollment.

22. Women who are breast feeding, pregnant, or planning to become pregnant, or are
unwilling to apply an effective birth control method while on study.