Swiss drugmaker Novartis said on Friday it is possible that employees of its Japanese unit violated clinical trial rules, Reuters reported.

Workers of Novartis Pharma K.K. (NPKK) are under fire for inappropriately transferring data on a cancer drug from research centers to University of Tokyo Hospital. The data was supposed to be passed directly to the hospital without any participation of Novartis employees, Top News reported.

NPKK said they are investigating the allegations.  

"NPKK has conducted employee trainings on proper protocol related to investigator-initiated clinical studies and believes that any involvement of our medical representatives in investigator-initiated clinical studies is inappropriate."

The documents contained information from a "not yet fully" enrolled 55-patient trial testing the Novartis cancer drug Tasigna, the company said.

"Novartis Pharma K.K. is aware of the media report regarding a small investigator-initiated clinical study ... conducted to assess side effects in patients with chronic myelocytic leukemia," Novartis said in a statement.

The number of test results being transferred by Novartis employees is still unclear.  Novartis doesn't know if other compliance rules have been breached in this incident or not.

After re-examining test results, the hospital said it had uncovered no evidence that Novartis employees had manipulated any of the data during the transfers, according to the Wall Street Journal report.