Minimal Residual Disease (MRD)

Minimal Residual Disease (MRD) refers to the small number of malignant cells that remain in a patient after treatment and are undetectable using conventional clinical assessments, yet capable of driving relapse. MRD detection is particularly important in haematological malignancies such as acute lymphoblastic leukaemia, multiple myeloma, and chronic lymphocytic leukaemia, where deep remission status strongly correlates with long-term outcomes. MRD assessment employs highly sensitive techniques including flow cytometry, next-generation sequencing, and PCR-based methods.

The biopharmaceutical industry increasingly uses MRD as a powerful biomarker for evaluating treatment efficacy, accelerating clinical development, and supporting precision oncology strategies. Clinical trials incorporate MRD negativity as an endpoint reflecting depth of response, enabling earlier assessment compared to overall survival and guiding treatment intensification or de-escalation. MRD monitoring supports personalised disease management, identifying early relapse signals and informing maintenance therapy decisions. Regulatory frameworks increasingly recognise MRD as clinically meaningful, particularly when supported by strong correlation with long-term outcomes and standardised assay validation. As MRD technologies improve in sensitivity and accessibility, MRD becomes central to modern haematology development strategies enabling more refined evaluation of therapies and improved long-term patient management.