Purdue University Graduate School
Browse
2022.04.21 Okezue.pdf (35.75 MB)

DEVELOPING MULTIPRONGED MODELS TO ENHANCE EFFECTIVENESS OF THE MANAGEMENT SYSTEM OF QUALITY CONTROL LABORATORIES. ADDITIONAL FOCUS ON SYNTHESIS AND CHARACTERIZATION FOR 5 NEW SALTS OF BEDAQUILINE

Download (35.75 MB)
thesis
posted on 2022-04-21, 19:19 authored by Mercy A OkezueMercy A Okezue

  

A multidisciplinary study that evaluated Quality Control (QC) laboratory (lab) accreditation, and a salt screen for bedaquiline. Medicines testing facilities always seek to ensure the accuracy of data from their QC labs by attaining accreditation. This research proposed that an understanding of the cross-linkages in the requirements for implementing the 2 most widely used lab standards will facilitate testing efficiencies, and reduce the risks of accreditation failures. For the salt project, the study proposed that new salts of bedaquiline will be formed from acid-base reactions following the pKa rule. Characterizing the salts will provide specifications for the new molecular entities, and form a selection-criteria for a lead candidate.

The research reviewed 2 lab standards: the ISO/IEC17025:2017 and the WHO Good Practices for Pharmaceutical QC labs, and identified the areas of overlap in their requirements. It then developed and tested affordable models that mitigate the 3 identified areas of high risks to lab accreditation. Additionally, it mixed equimolar amounts of bedaquiline base with select counterions that have ≥ 2 pKa units in organic solvents, to yield salts. ICHQ6 guidance was used to characterize the new salts.

The highest risks to laboratory accreditation were linked to 3 quality system metrics, namely: ‘Proficiency Testing’, ‘Validation’, and ‘Measurement Traceability’. Using the identified areas of overlap in the 2 laboratory standards, this research provided tutorial videos, a competency matrix, and some instrument validation data, to optimize the requirements for lab accreditation. For the salt screen, five new candidates were synthesized as alternatives to the existing fumarate salt of bedaquiline. The results of their physicochemical properties were used for selecting a lead moiety.

The research provided evidence that the multipronged models developed will improve efficiencies in QC labs, and increase their chances of attaining international accreditations. It also discovered the best modes for synthesizing the new salts of bedaquiline, and provided critical data to help Pharma make an informed choice for a lead candidate.

History

Degree Type

  • Doctor of Philosophy

Department

  • Agricultural and Biological Engineering

Campus location

  • West Lafayette

Advisor/Supervisor/Committee Chair

Kari Clase

Advisor/Supervisor/Committee co-chair

Stephen Byrn

Additional Committee Member 2

Lynn Taylor

Additional Committee Member 3

Anne Traynor