Kim, So Yeon

Importance Immune checkpoint inhibitors (ICIs) are efficacious in many cancer types but can produce immune-related adverse events (irAEs). As such, patients with preexisting autoimmune disorders are often excluded from clinical trials, although subsequent studies have shown that many of these patients have acceptable ICI tolerance. The safety and efficacy of ICIs among patients with preexisting neurologic autoimmune disorders (NAIDs) is not well characterized. Objective To evaluate the safety and clinical outcomes associated with ICI therapy among patients with NAIDs. Design, Setting, and Participants This multicenter retrospective cohort study included patients with cancer who were treated with ICIs between October 2013 and May 2023 and had preexisting multiple sclerosis (MS), myasthenia gravis (MG), Guillain-Barré syndrome (GBS), and other NAIDs as well as a control cohort of patients with Parkinson disease (PD). Exposure ICI therapy. Main Outcomes and Measures Demographic and clinical characteristics (neurologic disability, active or recent immunosuppression), ICI outcomes (response, progression-free survival [PFS], and overall survival [OS]), and safety outcomes (NAID exacerbation, irAEs) were collected. Results A total of 135 patients were included; the median (range) age was 72 (40-88) years, 84 (62%) were men, and 51 (38%) were women. A total of 45 patients had MS; 18, MG; 10, GBS; 5, another NAID; and 57, PD. Exacerbations occurred most frequently in MG (12 of 18 patients [67%]), often resulting in hospitalization (6 [50%]) or death (2 [17%]), with much lower rates in the MS cohort (8 of 45 patients [18%]). Ten patients with a history of GBS tolerated ICI without exacerbations, although 1 developed a fatal case of Lambert Eaton myasthenic syndrome following ICI treatment. No differences in response rate, PFS, or OS were observed between NAID groups. Conclusions and Relevance In this cohort study of ICI use in NAIDs, patients with MG had frequent and more severe exacerbations, while those with MS had few exacerbations. No obvious differences in survival between groups were observed. ICI may be an option for many patients with appropriate oncologic indications and preexisting NAIDs.

Background Patients with paraneoplastic syndromes (PNS) are excluded from clinical trials involving immune checkpoint inhibitors (ICIs) due to safety concerns. Moreover, real-world data on efficacy and safety is scarce. Methods In this retrospective study, data were collected on patients with PNS and solid tumors receiving ICI between 2015 and 2022 at nine institutions. Patients were classified into: Cohort 1 (pre-existing PNS before ICI initiation), cohort 2 (PNS during ICI treatment), and cohort 3 (PNS after ICI discontinuation). Patients with metastatic non-small cell lung cancer (NSCLC) (mNSCLC) from cohort 1 were matched to patients who were PNS-free at each institution up to a 1:3 ratio for age, sex, type of ICI, use of concurrent chemotherapy, and number of lines of systemic therapy prior to ICI initiation. Kaplan-Meier method was used to assess overall survival (OS) and time-to-next treatment (TTNT). Results Among 109 patients with PNS treated with ICIs, median age at ICI initiation was 67 years (IQR: 58–74). The most represented cancer type was NSCLC (n=39, 36%). In cohort 1 (n=55), PNS exacerbations occurred in 16 (29%) patients with median time to exacerbation after ICI of 1.1 months (IQR: 0.7–3.3). Exacerbation or de novo PNS prompted temporary/permanent interruption of ICIs in 14 (13%) patients. For cohort 2 (n=16), median time between ICI initiation and de novo PNS was 1.2 months (IQR: 0.4–3.5). Treatment-related adverse events (trAEs) occurred in 43 (39%) patients. Grade ≥3 trAEs occurred in 18 (17%) patients. PNS-directed immunosuppressive therapy was required in 55 (50%) patients. We matched 18 patients with mNSCLC and PNS (cohort 1) to 40 without PNS, treated with ICIs. There was no significant difference in OS or TTNT between patients with mNSCLC with and without PNS, although a trend was seen towards worse outcomes in patients with PNS. TrAEs occurred in 6/18 (33%) and 14/40 (35%), respectively. Grade ≥3 trAEs occurred in 4 (22%) patients with PNS and 7 (18%) patients without PNS. Conclusions Exacerbations of pre-existing PNS occurred in 29% of patients treated with ICIs and both exacerbations and de novo PNS occur early in the ICI course. TrAE from ICIs were similar between patients with and without PNS. Our data suggest that pre-existing PNS should not preclude consideration of ICI therapy although patients may not derive the same clinical benefit compared with patients without PNS.