Prevalence of Pathogenic Antibodies in Psychosis (PPiP) study


The PPiP study aims to understand if some cases of psychosis are caused by immune system problems in some people.



The immune system normally controls our ability to fight infection. If the immune system goes wrong it may cause diseases called ‘autoimmune’ diseases. We can diagnose some of these autoimmune diseases using blood tests. We are specifically interested in antibodies affecting the N-methyl D-aspartate receptors (NMDA-r) or other neuronal membrane targets that may be the cause symptoms of psychosis and possibly cause some cases of schizophrenia. We are working with Mental Health services across England to estimate the prevalence of these autoimmune diseases in people with first episode psychosis.


For more information on how to take part in the PPiP study, click here

PPIP 1 (closed)

The first phase of the PPiP study included patients from EIP

services between 14-35 years of age who were experiencing their

first episode of psychosis and had been taking antipsychotic

medication for less than 6 weeks.

This study included patients from over 30 sites across England.

PPiP-1 ceased recruitment on 30th December 2015.

Preliminary results can be found here.



PPIP 2 (ongoing)

The second phase of the PPiP study includes participants from inpatient and community mental health services between 18-70 years of age who are experiencing their first episode of psychosis or relapse of psychosis symptoms after remission (there needs to be a period of at least 6 months of remission prior to the current episode).

PPiP2 includes patients from over 30 sites across England and will

continue to recruit patients until the end of August 2020.


Through PPiP 2, we will identify individuals eligible to take part in the SINAPPS 2 study, testing a potential treatment for antibodies-mediated symptoms of psychosis.


If you, or someone you care for, is interested to take part in the PPiP 2 study, you can find more information here.

map_ppip sites_uk


Social Media

You can keep up to date with the PPiP study by following

@PPiPstudy on twitter

or visiting

PPiP 2 sites distribution