The PAPR Study

Powerful New Predictor of sPTB: Proteomics5

An analysis of 5,501 women in a landmark, prospective study—Proteomic Assessment of Preterm Risk or ‘PAPR’—published in American Journal of Obstetrics and Gynecology, showed that several distinct proteins measured in maternal serum are effective predictors of sPTB early in pregnancy before symptoms occur. The PAPR Study was conducted from 2011-2014 at eleven highly-respected clinical sites across the U.S.

Sera Prognostics developed a biomarker signature for sPTB using proteomic technology. The signature was validated to predict spontaneous preterm birth (sPTB) risk by measuring proteins that are over- or under-expressed and are predictive of premature birth (or delivery).

Validation Results Show Strong Performance of the Protein Signature5

The PAPR study validated the IBP4/SHBG signature using a novel proteomic approach and rigorously adhering to the authoritative Institute of Medicine guidelines for ‘omics prediction development.

Results showed strong prediction of sPTB occurring before 37 weeks and even higher predictive performance for delivery occurring before 35 weeks of pregnancy.

Predictive biomarkers

were discovered in this landmark study — a large contemporary, multisite, all-comer study. Eleven highly-respected clinical sites across the U.S. participated.

Blood samples

were prospectively collected from 5,501 women between 17-28 weeks gestation. This is the largest study of its kind and is representative of the intended use U.S. pregnant population.

Advanced technology

including proteomics, bioinformatics, and multidimensional data analysis was applied to PAPR samples to validate a proprietary biomarker signature designed to accurately predict a woman’s individual risk of delivering preterm. Validation and verification of target proteins was completed in 2015.

Non-Predictive vs Predictive Protein Expression in Pregnancy5

Over 300 proteins were analyzed in the PAPR Study

Normal Expression:
This example represents a pregnancy-related protein that is unaffected by preterm pathology.

Under-Expressed Protein (SHBG):
This example represents a biologically-important protein that is under-expressed in patients who went on to have sPTB.

Over-Expressed Protein (IBP4):
This example represents a biologically-important protein that is over-expressed in patients who went on to have sPTB.

IBP4/SHBG: Reversal:
This example represents the signature combination biologically-important proteins that are over-expressed (IBP4) and underexpressed (SHBG) in patients who went on to have sPTB.