Pathophysiology as a basis for understanding symptom complexes and therapeutic targets

Area of Science:

• Gastroenterology and Neurogastroenterology
• Pharmacology and Drug Development
• Biomarker Research

Background:

• Sensorimotor disorders of the gastrointestinal tract present with limited clinical manifestations, often involving multiple underlying mechanisms.
• Current clinical trial paradigms in neurogastroenterology rely heavily on broad symptom assessment using Rome criteria, which has led to the failure of potentially valuable drugs.
• This symptom-based approach may not adequately account for the heterogeneity of functional bowel diseases.

Purpose of the Study:

• To propose a shift from broad symptom assessment to a paradigm based on physiological testing for identifying homogeneous patient populations in functional bowel disease.
• To summarize evidence supporting the use of validated biomarkers in predicting therapeutic success for experimental medicines in common gastrointestinal disorders.
• To highlight the potential role of biomarker-driven approaches in improving drug development within neurogastroenterology.

Main Methods:

• Review and summarization of existing evidence on the use of biomarkers in predicting drug efficacy for functional gastrointestinal disorders.
• Focus on physiological measurements, particularly gastrointestinal transit time, as a validated biomarker.
• Analysis of clinical trial outcomes for drugs targeting conditions such as irritable bowel syndrome and functional dyspepsia.

Main Results:

• Certain biomarkers, notably transit measurements, have demonstrated a limited but convincing ability to predict the success of specific drugs (e.g., loperamide, alosetron, tegaserod, piboserod).
• The current evidence, while limited, supports the concept that validated and responsive biomarkers can guide therapeutic selection.
• This approach has the potential to identify more targeted patient subgroups for clinical trials.

Conclusions:

• Physiological testing should form the basis for identifying homogeneous patient populations and therapeutic targets in functional bowel disease, applicable to both upper and lower gastrointestinal tracts.
• The use of validated biomarkers in drug development holds significant promise for improving the success rates of novel agents in neurogastroenterology.
• A paradigm shift towards biomarker-guided drug development is recommended for common gastrointestinal disorders.