This study is broken down into 3 periods:

• Screening period
• Study drug period
• Follow-up period

If you decide to join this study, we will determine your eligibility during the screening period. This period lasts about 5 weeks and involves the following procedures:

Physical exam

Blood draws

Skin exam

Questionnaires

If you are eligible to join based on screening, you will get a random assignment (like pulling numbers from a hat) to receive either:

• A 300 mg dose of the study drug; OR
• A 600 mg dose of the study drug; OR
• A 1200 mg dose of the study drug; OR
• Placebo (inactive substance with no drug in it)

During the study drug period, you will receive the study drug or placebo on day 1 and then every 2 weeks after that. The study drug and placebo are given as injections (shots) under the skin. This study is "blinded," which means that you will not know if you are getting a dose of study drug or placebo. The study drug period will last for 52 weeks (1 year). If you remain in the study for the first 16 weeks of the study drug period, there might be a change to your regimen:

• If you were initially assigned to placebo, you will start getting a 1200 mg dose of the study drug once every 2 weeks and for the rest of the study drug period.
• If you were initially assigned to get a 1200 mg dose of the study drug, you will continue to receive the same dose once every 2 weeks for the rest of the study drug period.
• If you were initially assigned to get a 300 mg or 600 mg dose of the study drug, you may continue to receive the same dose or you may start receiving a 1200 mg dose once every 2 weeks for the rest of the study drug period. Whether or not your dose changes will be based on how your symptoms have responded to your beginning dose.

The follow-up period begins after the study drug period ends. During this period you will not receive any study drug, and it will last for about 10 weeks. You will visit our clinic for check-ups and we will keep in touch with you to see how you are doing.