BRIEFING

 Acyclovir for Injection. This proposal is based on the version of the monograph official as of April 1, 2022. It is proposed to revise the monograph with the following changes:

1. Add Identification B based on the UV spectra agreement as obtained in the Assay. Accordingly, revise the Detector in the Assay to support the proposed Identification B.

2. In the Assay:

   • Delete System suitability solution B as it is not needed to establish System suitability criteria. Accordingly, System suitability solution A is renamed as System suitability solution.

   • Replace guanine as a reagent with USP Guanine RS in the System suitability solution.

   • Replace the column which is not commercially available with a commercially available column of the same L1 packing and column length but different column diameter.

   • Revise the flow rate from "1.5 mL/min" to "1.8 mL/min" to align with column diameter change.

   • Add the Tailing factor in the Suitability requirements section.

   • Revise the System suitability requirements for the Relative standard deviation to be consistent with the expectations of a modern chromatographic system.

   • Update the sentence that comes before the calculation to be consistent with the Definition and include "nominal" in the concentration of the Sample solution in the Analysis section.

3. Add a new category for Performance Tests and the test for Uniformity of Dosage Units is moved from Specific Tests to Performance Tests.

4. In the test for Organic Impurities:

   • Delete the Acyclovir standard solution as it is not needed to establish System suitability criteria.

   • Revise the name of Guanine solution as Guanine stock solution and revise the preparation to provide flexibility.

   • Replace guanine as a reagent with USP Guanine RS in the System suitability solution.

   • Revise the names of Standard solution A and Standard solution B to be consistent with the order of calculation in the Analysis section for clarity.

   • Revise the concentration of Standard solution B to align with the level of any unspecified impurity and clarify the Standard solution B preparation.

   • Add the Sensitivity solution and Signal-to-noise ratio for acyclovir.

   • Add the Column particle size in the Chromatographic system.

   • Add Table 2 and update the Note in the System suitability section to present relative retention times as an aid in peak assignment.

   • Clarify the Analysis section by renaming the title Analysis 1 to Analysis and delete the title Analysis 2, as both acceptance criteria are included in the Acceptance criteria section.

   • Add Table 3 in the Acceptance criteria section to list the limits for specified impurities, any unspecified impurity, and total impurities.

5. Revise the Bacterial Endotoxins Test requirement to remove the numerical limit and instead refer to Bacterial Endotoxins Test 〈85〉 for the determination of limits.

6. Update the USP Reference Standards section to include USP Guanine RS to support the proposed changes in the Assay and Organic Impurities tests.

 Additionally, minor editorial changes have been made to update the monograph to current USP style.

 (SM1: S. Parepalli)

 Case ID—SUB-997