Comprehensive characterization of bremelanotide acetate and its degradants by LC-HRMS/MS and predicting epimerization...

Area of Science:

• Analytical Chemistry
• Pharmaceutical Sciences
• Computational Chemistry

Background:

• Bremelanotide (BRM) is a cyclic peptide therapeutic.
• Its stability and degradation profile require thorough investigation for safe and effective use.
• Understanding degradation is crucial for API development and formulation.

Purpose of the Study:

• Develop a stability-indicating RP-HPLC method for bremelanotide (BRM).
• Characterize BRM degradation products using LC-HRMS/MS and computational methods.
• Investigate BRM stability under various stress conditions.

Main Methods:

• Forced degradation studies under ICH guidelines (acidic, basic, oxidative, thermal, photolytic).
• RP-HPLC method development using a C8 column and gradient elution.
• LC-HRMS/MS for degradation product identification and characterization.
• Computational approaches for predicting epimerization sites and toxicity.

Main Results:

• A validated RP-HPLC method with excellent linearity (r²=0.9993).
• BRM showed lower degradation in acidic vs. basic conditions and susceptibility to oxidation.
• Eight degradation products identified, mainly via deacetylation, hydrolysis, oxidation, and epimerization.
• In silico toxicity prediction indicated low to moderate toxicity for degradation products.

Conclusions:

• The developed method is suitable for BRM stability assessment.
• Degradation pathways include deacetylation, hydrolysis, oxidation, and epimerization.
• Findings support bremelanotide API/formulation development, impurity profiling, and quality control.