Oral bioavailability
Peptide Membrane Permeability and Oral Bioavailability Optimization
Oral bioavailability remains one of the most significant barriers to peptide drug development. Achieving adequate passive membrane permeability and GI stability requires systematic optimization of molecular properties — hydrogen bond donors, lipophilicity, conformational flexibility, and backbone modification. We apply computational methods to engineer peptide candidates with improved membrane permeability and oral bioavailability potential.
The Oral Peptide Challenge
Most peptide drugs require parenteral administration because they are rapidly degraded in the GI tract and have poor passive membrane permeability. The beyond-rule-of-5 space occupied by peptides presents a fundamental challenge to oral delivery — high molecular weight, multiple hydrogen bond donors, and conformational flexibility all work against passive absorption.
Achieving oral bioavailability for peptides requires a multi-pronged approach: reducing hydrogen bond donors through N-methylation or backbone modification, improving lipophilicity, constraining conformation through cyclization, and engineering GI stability through protease-resistant modifications.
Our Permeability Optimization Approach
HBD reduction strategies
N-methylation, backbone modification, and cyclization to reduce hydrogen bond donors and improve passive permeability.
Lipophilicity optimization
Systematic adjustment of lipophilicity through residue substitution and modification to improve membrane partitioning.
GI stability engineering
Protease-resistant modifications — D-amino acids, N-methylation, beta-amino acids — to improve stability in GI conditions.
Conformation-permeability modeling
Computational modeling of the relationship between conformational flexibility and membrane permeability to guide design.
Permeability Optimization Workflow
Candidate assessment
Analysis of current permeability barriers and identification of key physicochemical liabilities.
Modification strategy design
Computational design of modifications to address permeability and stability liabilities.
Analog generation
Design of modified analogs with predicted improved permeability profiles.
Property prediction
Prediction of Papp, GI stability, and oral bioavailability potential for candidate analogs.
Experimental validation
Caco-2 permeability, GI stability, and in vivo PK assessment of priority analogs.
Iterative optimization
Refinement based on experimental permeability and PK data.
What Can Be Evaluated
What You May Receive
Permeability-optimized analog series
Modified peptide analogs with predicted improved membrane permeability and GI stability.
Permeability liability analysis
Identification of key physicochemical barriers and recommended modification strategies.
Modification strategy report
Rationale for selected modifications and predicted impact on permeability and activity.
Experimental validation plan
Recommended assay cascade for permeability and oral bioavailability assessment.
Deliverables depend on project scope and starting peptide properties. Oral bioavailability cannot be guaranteed computationally.
Who This Is For
Medicinal chemists
Teams working on peptide candidates where oral delivery is a development requirement.
Drug discovery groups
Programs where parenteral administration is a commercial or patient compliance limitation.
Biotech companies
Companies developing oral peptide therapeutics or seeking to improve the bioavailability of existing candidates.
Frequently Asked Questions
Optimize Peptide Membrane Permeability for Oral Delivery
Submit your peptide candidate and permeability objectives. We will assess the optimization opportunity and outline a computational approach to improve oral bioavailability.
Confidential project discussions available under NDA.