Clinical characteristics, treatment and outcome of nivolumab-induced myasthenia gravis.

BACKGROUND

To investigate the clinical features of nivolumab-induced myasthenia gravis (MG) and provide evidence for the rational use of nivolumab in the clinic.

METHODS

We collected case reports and case series of nivolumab-induced MG for retrospective analysis by searching Chinese and English databases from 2014 to October 31, 2022.

RESULTS

Of the 67 patients included, the median age was 72.5 years (range 34-86), including 44 males (65.7%). MG occurred in the median 2nd treatment cycle (range, 1st-6th) after nivolumab treatment, being mild in 12 patients (17.9%) and moderate to severe in 44 patients (65.7%). Ptosis (n = 48,71.6%), diplopia (n = 34,50.7%), dyspnea (n = 30, 44.8%), limb muscle weakness (n = 30, 44.8%) and dysphagia (n = 27, 40.3%) were the most common symptoms. Fifty-six patients (83.6%) were classified as having generalized myasthenia gravis (GMG), the remaining 11 patients (16.4%) isolated ocular myasthenia gravis (OMG). Twenty-one patients (31.3%) had MG combined with myositis, 10 patients (14.9%) had myocarditis, and 9 patients (13.4%) had both myositis and myocarditis. Forty patients (59.7%) were positive for anti-acetylcholine receptor antibodies. The serum creatine kinase level was significantly increased in 37 patients (55.2%), with a median value of 4000 IU/L (219,14229). After discontinuation of nivolumab and immunosuppressive therapy, 46 patients (68.7%) finally recovered or improved their MG symptoms, while 15 patients (22.4%) did not recover. Eleven patients (16.4%) died of MG complications.

CONCLUSION

MG is a serious and rare adverse reaction to nivolumab. Nivolumab-induced MG should be timely and correctly identified, and immunotherapy should be given.