Product Quality Research Initiative and Bulk Actives Post Approval Change


Based upon the success achieved by Scale-Up and Post Approval Change (SUPAC) in reducing the regulatory burden for drug product postapproval manufacturing change, a Food and Drug Administration (FDA), industry, and academic collaborative arrangement called the Product Quality Research Initiative (PQR1) was founded. Its objective was to foster and execute research programs designed to permit a broader application of the SUPAC principles for the regulatory reduction of postapproval manufacturing changes to drug substance and drug product operations. In the drug substance area, the PQRI Technical Committee developed an umbrella hypothesis and from that, three research initiatives to use as the core for the structure of specific research programs. The projects relate to: 1. The significance of specifications, 2. Drug substance physical properties, and 3. Drug substance impurities. The following paper discusses these aspects of PQRI, affords a detailed perspective of the objectives and organization of PQRI, and explains the relationship between Bulk Actives Post Approval Change (BACPAC) and SUPAC.

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Correspondence to Daniel H. Gold PhD.

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Gold, D.H., Byrn, S. Product Quality Research Initiative and Bulk Actives Post Approval Change. Ther Innov Regul Sci 33, 777–784 (1999).

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Key Words

  • PQRI
  • Drug substance
  • Specifications
  • Impurities
  • Physical properties