Merck discovers 'root cause' of nitrosamine levels in blockbuster diabetes drugs

Merck has identified what caused levels of the nitrosamine NTTP to appear in batches of its blockbuster diabetes drugs, the company confirmed on Wednesday.

An unnamed source told Bloomberg, which first reported the news, that NTTP contamination in certain batches of its sitagliptin diabetes products Januvia and Janumet occurred during storage and manufacturing processes.