Again it looks like a very low risk and possibly from a combination of drugs... but I would really like to take PML out behind the shed and have a word with it.
FDA investigates CellCept and Myfortic PML risk
The FDA is investigating a possible link between the use of CellCept (mycophenolate mofetil, from Roche) and Myfortic (mycophenolic acid, from Novartis) and the development of progressive multifocal leukoencephalopathy (PML).
The FDA is reviewing Roche’s PML cases and the proposed revisions to the CellCept labeling. The FDA has also asked Novartis for their PML data and requested that they revise their Myfortic prescribing information to include the same information as Roche’s proposed CellCept revisions. Until further information is available, clinicians should be aware of the risk of PML with CellCept and Myfortic therapy and should monitor for localized neurologic signs and symptoms.
CellCept is approved to prevent heart, liver, and kidney transplant rejection and Myfortic is approved to prevent kidney transplant rejection.
For more information call Roche at (800) 526-6367, Novartis at (888) 669-6682, or visit http://www.fda.gov/medwatch/safety/2008/safety08.htm#mycophenolate.
Another article where they provide more context: FDA Launches Safety Review of Two Antirejection Agents