BRIEFING

 Levonorgestrel Intrauterine System. Because there is no existing USP monograph for this drug product, a new monograph is being proposed based on validated methods of analysis.

1. The liquid chromatographic procedures in the Assay and Drug Release Test 1 were validated using the Zorbax SB-C18 brand of column with L1 packing. The typical retention time for levonorgestrel is about 5.3 min.

2. The liquid chromatographic procedure in Drug Release Test 2 was based on analyses performed with the LiChrospher 100 RP-18 brand of column with L1 packing. The typical retention time for levonorgestrel is about 7.5 min.

3. The liquid chromatographic procedure in the Organic Impurities test was validated using the SymmetryShield RP8 brand of column with L7 packing. The typical retention time for levonorgestrel is about 20 min.

 (SM5: M. Chang)

 Case ID—SUB-1115, SUB-1116