In certain people whose myasthenia gravis (MG) has been in stable remission for a long time, using the immunotherapy Opdivo (nivolumab) to treat a relapsed lymphoma may be possible, researchers in Germany report.
Their case study differs from others that linked treatment with immunotherapies like Opdivo to a higher risk of myasthenia gravis in cancer patients. Such cases are rare and amount to “fewer than 1% of patients,” they noted, but can be severe.
Opdivo, by Bristol-Myers Squibb, is a monoclonal antibody that blocks a protein called PD-1 (programmed cell death-1) present on the T-cells. PD-1 is used by cancer cells to evade the immune system. (The treatment is called an immune checkpoint inhibitor, because Opdivo works to block certain proteins made by immune cells to limit immune responses. As such, it helps T-cells in the immune system better detect and kill cancer cells.)
By activating immune responses in this way, Opdivo may also trigger or aggravate autoimmune diseases such as myasthenia gravis.
Researchers describe a case of a 49-year old woman whose MG was in complete remission when she was found to have lymphoma, and was given Opdivo as a maintenance therapy.
At age 21, the woman was diagnosed with acetylcholine receptor antibody-positive MG. Her thymus gland was surgically removed (thymectomy), and she was treated with prednisone for the first eight months, followed by Mestinon (pyridostigmine) and azathioprine for 24 months. She achieved complete and stable remission one year after treatment.
Fourteen years later, in her mid-30s, she was diagnosed with primary central nervous system lymphoma. High-dose chemotherapy followed by autologous stem cell transplant led to remission. The cancer returned twice in the next 11 years, and again was successfully treated. After the third remission, however, she was given 24 cycles of Opdivo at a dose of 3 mg/kg twice a month as a maintenance therapy to prevent relapse.
At this point, stable remission of her myasthenia gravis had been maintained for 25 years, the researchers noted.
Over a year (36 months) after the Opdivo treatment, she had no evidence of MG — or her lymphoma — returning, the study said.
“[O]ur case underscores the fact that treatment may be feasible in selected MG patients with longstanding CSR [clinically stable remission,” the researchers concluded. “Careful clinical monitoring is essential to recognize myasthenic symptoms immediately in these patients.”