Researchers have reported the first published case of lymphoma in a multiple sclerosis (MS) patient taking teriflunomide (Aubagio) -- and they also found 10 other cases in an international pharmacovigilance database.
A 54-year-old black woman with MS developed follicular lymphoma after 8 months on teriflunomide -- and the "timing of teriflunomide exposure was consistent with the onset of lymphoma," Anne Landais, MD, of University Hospital of Pointe-a-Pitre in Guadeloupe, France, and colleagues reported online in .
"So although there is no direct evidence confirming the role of the drug, we believe that it is useful to alert the medical community to this case," they wrote.
When they searched the literature, Landais and colleagues found no reports linking teriflunomide with lymphoma. But when they checked the World Health Organization's VigiBase -- a global database of safety reports -- they found 10 more cases of lymphoma with teriflunomide, and 82 more with leflunomide, of which teriflunomide is the active metabolite.
Although the researchers acknowledged that more than 70,000 patients have been treated with teriflunomide as of April 2017, questions remain, the team noted, about immunosuppressive drugs in MS and cancer risk.
"Ultimately, only the development of registries, databases, and national and international observatories with the combined efforts of all neurologists will help answer the question of the risk of cancer associated with the use of treatment for MS," the researchers wrote.
The woman had no risk factors for lymphoma; indeed, black women in the U.S. have a threefold lower risk of developing the cancer compared with white women in the U.S., Landais and colleagues noted.
The patient did have a history of having a thyroidectomy for multinodular goiter, as well as surgery for a mammary adenofibroma and a uterine fibroid. But the researchers noted that the levothyroxine she was taking for thyroid hormone replacement has never been tied to lymphoma risk.
The patient had developed her first MS symptoms in 2013 and was eventually diagnosed with MS, for which she started teriflunomide in June 2015. In February 2016, she noticed an inguinal ganglion that was about 2 to 3 cm in diameter. By May, she was diagnosed with grade 1-2 follicular B-cell lymphoma. She stopped teriflunomide the next month and started on glatiramer acetate in July.
There was no clear signal from teriflunomide clinical trials regarding cancer risk, although an extension of a phase II trial reported five cancer cases, all of which occurred in patients taking the drug.
The researchers also noted that the 82 globally reported lymphoma cases with leflunomide could be of concern, given that teriflunomide is its active metabolite. With leflunomide, research has shown an increased incidence of malignant lymphoma in male mice given 15 mg/kg of the drug daily.
"An association between teriflunomide and higher risk of lymphoma can't be ruled out," the team concluded.
Disclosures
Landis disclosed a financial relationship with Novartis.
Primary Source
Multiple Sclerosis and Related Disorders
Landais A, et al "A case of lymphoma in a patient on teriflunomide treatment for relapsing multiple sclerosis" Multiple Sclerosis and Related Disorders 2017; DOI 10.1016/j.msard.2017.07.001