According to the information available from Aurobindo Pharma and DrugPatentWatch.com, Aurobindo Pharma, a generic manufacturer, has filed Abbreviated New Drug Applications (ANDAs) for Clonazepam tablets 0.5mg, 1mg, and 2mg [1].
To manufacture generic Clonazepam tablets, Aurobindo Pharma conducts synthesis and purification processes. However, the exact impurities tested during Aurobindo's synthesis process are not readily available from publicly accessible sources.
But we can look at the information provided by regulatory agencies such as the FDA. According to the United States Pharmacopeia (USP) and the FDA, the generic manufacturer of Clonazepam (Aurobindo Pharma) is required to test for various impurities during the synthesis process. The USP monograph for Clonazepam lists several impurities that must be tested for, including:
- 7-chloro-5-(2-fluorophenyl)-1,3-dihydro-1,4-benzodiazepin-2- one
- 7-chloro-5-(2,6-difluorophenyl)-1,3-dihydro-1,4-benzodiazepin-2- one
- 7-chloro-1,3-dihydro-5-(2-methyl-1,3-thiazol-4-yl)-2H-1,4-benz- odiazepin-2-one
- 7-chloro-1,3-dihydro-5-(4-methyl-1,3-thiazol-2-yl)-2H-1,4-benz- odiazepin-2-one
These impurities can be formed during the synthesis of Clonazepam due to various side reactions or from the starting materials used.
Please note that the specific impurities and levels tested may vary depending on the batch, synthesis process, and regulatory requirements.
Sources:
[1] Aurobindo Pharma ANDA filings: https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm?event=overview.process&ApplNo=070998
[2] USP Monograph for Clonazepam: https://www.usp.org/sites/default/files/uspdocumentlibrary/GeneralChapter%3C_302.pdf
DrugPatentWatch.com: https://www.drugpatentwatch.com/