Abstract: TH-PO1106
Utility of a Novel dd-cfDNA Test to Detect Injury in Renal Post-Transplant Patients
Session Information
- Transplantation: Clinical - Predictors of Outcomes - Biomarkers and Beyond
November 07, 2019 | Location: Exhibit Hall, Walter E. Washington Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 1902 Transplantation: Clinical
Authors
- Demko, Zachary, Natera, San Carlos, California, United States
- Valdenor, Czarlota, QURE Healthcare, San Francisco, California, United States
- Billings, Paul Richard, Natera Inc, Berkeley, California, United States
- Paculdo, David, QURE Healthcare, San Francisco, California, United States
- Novinson, Daniel, QURE Healthcare, San Francisco, California, United States
- Peabody, John, QURE Healthcare, San Francisco, California, United States
Background
Serum creatinine (SC) and biopsy are the standard of care for detecting renal allograft injury and rejection. SC has poor specificity and sensitivity, and biopsies are costly, invasive, and have attendant complications.
We report on the clinical utility of a novel method that measures donor-derived cell-free DNA (dd-cfDNA) using a single SNP-based NGS methodologyto diagnose allograft injury/rejection.
Methods
We conducted a randomized controlled trial sampling 154 fellowship-trained nephrologists with two to 40 years of post-residency practice and an active panel of at least five renal allograft patients.
Over two rounds, providers cared for six online, virtual patients—Clinical Performance and Value (CPV) vignettes—a validated tool that accurately measures clinical utility and clinical practice.CPV patients were aged 30-75, were 3-24 months post-transplant, and presented in one of three ways: (1) active rejection with moderate SC increase and proteinuria; (2) subclinical rejection with no change in SC; and (3) elevated SC from another nephrotoxic insult but not rejection.
Doctors randomized into the intervention arm were given educational materials on the dd-cfDNA test between rounds and dd-cfDNA results before they cared for patients in round 2.
The primary outcome determined whether using dd-cfDNA demonstrated clinical utility and improved patient care as manifested by the workup, diagnostic accuracy, and medical management of these patients.
Results
At baseline, providers correctly determined primary diagnosis in only 50% of cases (p=0.853). In round 2, intervention providers improved 32.9 percentage points (p<0.001); control providers did not improve (p=0.257).
Providers in both groups made a correct biopsy or referral decision in 58% of cases at baseline. Intervention improved 30.0 percentage points (p<0.001) while control did not improve in round 2 (p=0.501).
Similarly, intervention providers’ medical management improved significantly (+14.3 percentage points, p<0.001) in round 2, while controls’ did not (p=0.483).
Conclusion
Nephrologists shown dd-cfDNA levels were significantly more likely to accurately diagnose, and make better biopsy, referral and medically management decisions for renal transplant patients.