Prothena: Ph3 (Amyloidosis)

We are doing this study to find out if an experimental drug called birtamimab (the study drug) is a safe and effective treatment for amyloidosis. We want to find the most appropriate dose and schedule to give patients the study drug.

Mayo Stage IV with Amyloidosis

Adults ages 18+ who:

• Have amyloidosis that is not responding to therapy; OR
• Have amyloidosis that has come back after previous therapy

For more information about who can join this study, please contact the study team 919-668-0613.

This study has three periods: a screening period, the study drug period, and a follow-up period.

If you choose to join this study, during the screening period you will:

• Have a physical exam
• Have blood draws
• Give urine samples
• Have imaging tests (X-Ray, MRI/CT/PET scans)
• Have a bone marrow biopsy

You will proceed to the study drug period if you are eligible after screening.

The study is double-blinded, which means that you, your study doctor, and the study staff will not know if you are getting the study drug, but your study doctor can find out if there is an emergency or if it is necessary to know for your health. This study design is the best way to measure the effect of the study drug. When the study drug period ends, you will come back to our clinic a few more times for check-ups. If you are assigned to the study drug group, you will receive a dose of 24 mg/kg, up to a maximum of 2,500 mg, for each dose. If you receive placebo, then you will receive the same amount, about 250 mL of 0.9% saline. You will receive study drug or placebo about every 28 days.