Two cases of PML in MS patients taking Tysabri
The FDA notified healthcare professionals of two new cases of progressive multifocal leukoencephalopathy (PML) in European patients receiving natalizumab (Tysabri) monotherapy for multiple sclerosis (MS) for more than 1 year. PML is a known risk of Tysabri, but previous cases in MS patients were seen in combination with other immunomodulatory therapies.
In the United States, natalizumab is available only to patients with relapsing MS or Crohn's disease enrolled in the TOUCH risk minimization program. The program closely monitors every patient receiving natalizumab and follows them for the development of PML and other serious opportunistic infections.
Although the two new European patients were taking natalizumab as monotherapy, the FDA believes that natalizumab monotherapy may confer a lower risk of PML than when the drug is used together with other immunomodulatory medications.
Healthcare professionals should continue to monitor patients for signs and symptoms of PML, and the drug should not be infused if PML is suspected.
Pancreatitis noted in patients taking exenatide
The FDA has received reports of six cases of hemorrhagic or necrotizing pancreatitis in patients taking exenatide (Byetta) since the agency issued a letter on the issue to healthcare professionals in October 2007. All six patients required hospitalization. The drug was discontinued in all six cases.
The FDA advises that exenatide and other potentially suspect drugs be promptly discontinued if pancreatitis is suspected. There are no signs or symptoms that distinguish acute hemorrhagic or necrotizing pancreatitis associated with exenatide from the less severe form of pancreatitis, the agency notes.
The FDA states that if pancreatitis is confirmed, appropriate treatment should be initiated and the patient should be carefully monitored until recovery. Byetta should not be restarted. Antidiabetic therapies other than exenatide should be considered in patients with a history of pancreatitis.
FDA approves bone marrow stimulator for chronic ITP
Romiplostim (Nplate) became the first medication approved by the FDA to directly stimulate bone marrow to produce needed platelets in patients with chronic immune thrombocytopenic purpura (ITP). Romiplostim is approved only for patients with chronic ITP who do not respond sufficiently to current treatments.
The FDA based its approval of romiplostim on clinical trials of about 125 patients who received at least one prior ITP treatment. During 6 months of treatment, patients who received romiplostim showed significantly higher platelet counts and maintained them compared with those who did not receive the drug.
Safety concerns associated with romiplostim include fibrous deposits in the bone marrow and the possibility that once the treatment is stopped, platelet counts could drop below pretreatment levels.
Additional risks include thromboembolic complications due to excessive increases in platelets and a risk of acute leukemia in patients with myelodysplasia.
Two lots of ADHD patch recalled
Noven Pharmaceuticals Inc. and Shire voluntarily recalled their methylphenidate transdermal system, Daytrana, because of difficulties removing the release liner when the patch is peeled open. The recalled lots are 2819811 and 2764211 (NDC number 54092-553-30).
The recall is not due to safety concerns, but is being undertaken because the lots do not meet product specifications. The companies said that because the problem is not a safety issue, all Daytrana patches-including the ones in the lots being recalled-can continue to be used unless the release liner cannot be removed or the patches are damaged while being opened.