Novartis is apologizing to Japan after the Ministry of Health, Labor and Welfare said the company had dragged its feet reporting adverse events associated with its leukemia drugs Gleevec and Tasigna.

Reuters reports that Novartis knew there was a problem, because complaints started surfacing in April 2013, but that the drugmaker did not inform Japan’s agency until April of this year. The ministry tells Reuters the rule is that companies need to tell the health agency about adverse events within a month.

Thursday’s news is another blow for the company’s local image—a former Novartis employee has been accused of falsifying data in promotions for the blood pressure drug Diovan.