The purpose of this study is to learn more about long-term safety (good or bad effects) of avacopan and its efficacy (how well it is working) in treatment of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis.

Avacopan is currently approved as an adjunctive (another treatment used along with primary treatment) treatment in adult people with severe active ANCA-associated vasculitis in the US and is also approved in the EU, Canada, Japan, and other countries.

In this study, avacopan will be compared with a placebo (a drug that looks likes the study medication but does not contain any medication). This is a randomized study, meaning that you will be assigned by chance (like flipping a coin) into a treatment group. You will have an equal chance of being placed in either of the 3 following groups: treatment with avacopan for 5 years in group A, or treatment with avacopan for 1 year followed by placebo for 4 years in group B, or treatment with placebo for 5 years in group C. The study is also a double-blinded study, meaning you and your study doctor will not know what you are receiving, the avacopan or placebo.

The study is sponsored by Amgen, Inc. Participation in the study will require 27 visits to the MUSC main campus over approximately 63 months, and visits will include the following procedures: blood draw, urine collection, physician-led assessments of your disease (for example physical exam and medical history review), and health questionnaires. You will also be provided with a paper diary to record any missed doses/overdoses of the study drug.

Compensation is available for participation.

The purpose of this study is to test whether a drug called NS-229 (the study drug) is a potential treatment for patients with Eosinophilic Granulomatosis With Polyangiitis (EGPA).

NS-229 is an investigational drug that is provided in an oral pill form. An investigational drug is not approved by The US Food and Drug Administration. It can only be used in a research study like this one. In this study, NS-229 will be compared with a placebo (dummy drug), having no active drug in it. This is a randomized study, meaning that you will be assigned by chance (like flipping a coin) to receive either the study drug or placebo. The study is also double-blinded study, meaning you and your study doctor will not know what you are receiving, the NS-229 or placebo.

The study is sponsored by a NS Pharma, Inc. Participation in the study will require 12 visits to the MUSC main campus over approximately 8 months. Visits are much like the your standard of care and include the following procedures: blood draw, urine collection, physician-led assessments of your disease (for example physical exam and medical history review), tests to assess your lung function and health (Pulmonary Function Test (PFT) and spirometry, health questionnaires. You will also be asked to complete a daily diary regarding your medication use and vasculitis symptoms.

Compensation is available for participation