NPPB and pulmonary arterial hypertension: Recently, Brain Natriuretic Peptide (BNP) has been proposed as a good biomarker for assessing prognosis and follow-up in pulmonary arterial hypertension.[23] Another example of development of new biomarker under the aegis of CPI is that of protein degradation fragments called neoepitopes which have proven useful for research on bone and cartilage and are collagen type I and collagen type II degradation products, respectively.