A phase III, randomized, double-blinded, placebo-controlled multicenter trial to evaluate the efficacy, safety and tolerability of efgartigimod PH20 SC administered by prefilled syringe (PFS) in adult patients with primary Sjogren’s syndrome (pSS)

This is a phase 3 trial with to evaluate the efficacy, safety, and tolerability of efgartigimod P20 and find out what effects, if any, this new therapy has on people with Primary Sjögren’s Disease (PSjD). People with this condition may experience dryness in their eyes, mouth, and skin. These symptoms are caused by the immune system attacking parts of the body that produce fluids, like tears and saliva. PSjD can also affect other body parts, such as the skin and joints. This can cause people with PSjD to experience muscle weakness, joint pain, changes in taste, and tiredness.Efgartigimod is a fragment of a human antibody that has been modified to bind better to a protein called neonatal Fc receptor (FcRn). Antibodies are proteins that the body uses to fight and prevent infections. In some diseases, antibodies can attack your own body. The FcRn protein keeps the antibody level up. The levels of antibodies are reduced after efgartigimod binds to FcRn. This means that the levels of antibodies attacking the body may also be reduced.The study will consist of the following 4 time periods: Screening (up to 4 weeks): participants will complete some tests and assessments during the screening period to confirm if the study is suitable.Double-blinded treatment (48 weeks): participants will be randomised in a 1:1 ratio to receive either the study drug or placebo once a week.Open-label extension (OLE) (48 weeks): participants will receive the study drug once a week for 4 weeks, and then once every two weeks for the rest of the treatment period.Safety follow-up period (8 weeks after the last study medication dose)The estimated duration on study for each participant is up to 107 weeks (~2 years and 3 weeks)This study is expected to include ~580 participants worldwide.