TruGraf Liver Gene Expression Serial Test

Study Abstract Following liver transplantation, organ recipients require long-term immunosuppression therapy along with frequent surveillance of the transplanted graft for indications of rejection, injury or failure. Long-term death rates in liver transplantation are more often attributable to long-term intake of immunosuppression medications than to liver graft dysfunction. Excessive immunosuppression can lead to declining kidney function, recurrent infections and other issues especially in the aging recipient population while suboptimal immunosuppression can lead to allograft injury, rejection or failure.

Monitoring for graft health post-transplant typically relies upon measurements of immunosuppression drug levels, serum liver enzyme testing, clinical symptoms of graft rejection and invasive liver biopsies. The measurement of serum liver enzymes may not reflect the full story as these enzymes are insensitive for predicting immune response and are considered to be late indicators of organ injury and/or damage given that by the time the enzymes are elevated the liver damage may have already occurred.

Currently, the gold standard for the detection of subclinical (before definitive, observable symptoms) graft injury is an invasive liver biopsy. Many times liver grafts will have abnormal histological findings late after transplantation despite having normal liver enzymes. Also, interpretation may be difficult in the presence of infection or recurrence of primary disease. As discussed, standard liver enzyme blood tests are non-specific and have an insensitivity for detecting subclinical graft injury. There is a need for non-invasive biomarkers to predict the onset and severity of rejection and improvement in histological markers to make an accurate diagnosis.

The identification of non-invasive biomarkers for subclinical graft injury to help individualize immunosuppression therapy especially in patients with autoimmune liver diseases will allow for better management of allograft protection along with improved management of adverse side effects. In this study, non-invasive biomarker assessment will be performed, utilizing TruGraf liver gene expression testing, to serially monitor for early immune activation prior to acute rejection with the aim to inform immunosuppression therapy management in liver transplant recipients with autoimmune diseases of the liver.

Primary Hypothesis Can utilization of Trugraf Liver gene expression testing to alter immunosuppression (IS) protocols in liver transplant recipients with autoimmune disease reduce the need for post-transplant liver biopsy as well as 1-year graft rejection rates as compared to a matched historical control group?

Inclusion criteria

• Recipients ≥18 years of age
• Currently waitlisted for liver transplant or recipient of liver transplant within the last 30 days
• Primary indication for transplant due to autoimmune hepatitis (AIH) - Primary Biliary Cirrhosis (PBC) or Primary Sclerosing Cholangitis (PSC) etiologies
• First time, single-organ liver transplant recipient
• Willing and able to undergo protocol required TruGraf serial blood draws

Exclusion criteria

• Recipient <18 years of age
• Recipients of multi-organ or repeat transplantation
• Grafts from donors with HIV
• Grafts from donors with viremic Hepatitis A, B, C
• Inability to meet study requirements