Mortality and immune-related adverse events after immune checkpoint inhibitor initiation for cancer among patients with pre-existing rheumatoid arthritis: a retrospective, comparative, cohort study

Pre-existing Autoimmune Diseases and Immune Checkpoint Inhibitors for Cancer Treatment: Considerations About Initiation, Flares, Immune-Related Adverse Events, and Cancer Progression

Immune checkpoint inhibitors (ICIs) are increasingly used to treat a variety of cancer types. Patients with preexisting autoimmune diseases may be vulnerable to underlying disease flare as well as immune-related adverse events from ICIs. There has also been concern that immunosuppression needed to control the autoimmune disease may blunt ICI efficacy. Much of the literature is focused on diverse preexisting autoimmune diseases, which may limit conclusions to specific diseases. There is a growing literature of specific diseases, such as preexisting rheumatoid arthritis, investigating outcomes after ICI.

Clinical and translational attributes of immune-related adverse events

With immune checkpoint inhibitors (ICIs) becoming the mainstay of treatment for many cancers, managing their immune-related adverse events (irAEs) has become an important part of oncological care. This Review covers the clinical presentation of irAEs and crucial aspects of reversibility, fatality and long-term sequelae, with special attention to irAEs in specific patient populations, such as those with autoimmune diseases. In addition, the genetic basis of irAEs, along with cellular and humoral responses to ICI therapy, are discussed. Detrimental effects of empirically used high-dose steroids and second-line immunosuppression, including impaired ICI effectiveness, call for more tailored irAE-treatment strategies. We discuss open therapeutic challenges and propose potential avenues to accelerate personalized management strategies and optimize outcomes.

Immunomodulator use, risk factors and management of flares, and mortality for patients with pre-existing rheumatoid arthritis after immune checkpoint inhibitors for cancer

OBJECTIVE

To investigate immunomodulator use, risk factors and management for rheumatoid arthritis (RA) flares, and mortality for patients with pre-existing RA initiating immune checkpoint inhibitors (ICI) for cancer.

METHODS

We performed a retrospective cohort study of all patients with RA meeting 2010 ACR/EULAR criteria that initiated ICI for cancer at Mass General Brigham or Dana-Farber Cancer Institute in Boston, MA (2011-2022). We described immunomodulator use and changes at baseline of ICI initiation. We identified RA flares after baseline, categorized the severity, and described the management. Baseline factors were examined for RA flare risk using Fine and Gray competing risk models. We performed a landmark analysis to limit the potential for immortal time bias, where the analysis started 3 months after ICI initiation. Among those who survived at least 3 months, we examined whether RA flare within 3 months after ICI initiation was associated with mortality using Cox regression.

RESULTS

Among 11,901 patients who initiated ICI for cancer treatment, we analyzed 100 pre-existing RA patients (mean age 70.3 years, 63 % female, 89 % on PD-1 monotherapy, 50 % lung cancer). At ICI initiation, 71 % were seropositive, 82 % had remission/low RA disease activity, 24 % were on glucocorticoids, 35 % were on conventional synthetic disease-modifying antirheumatic drugs (DMARDs), and 10 % were on biologic or targeted synthetic DMARDs. None discontinued glucocorticoids and 3/35 (9 %) discontinued DMARDs in anticipation of starting ICI. RA flares occurred in 46 % (incidence rate 1.84 per 1000 person-months, 95 % CI 1.30, 2.37); 31/100 flared within 3 months of baseline. RA flares were grade 1 in 16/46 (35 %), grade 2 in 25/46 (54 %), and grade 3 in 5/46 (11 %); 2/46 (4 %) required hospitalization for RA flare. Concomitant immune-related adverse events occurred in 15/46 (33 %) that flared. A total of 72/100 died during follow-up; 21 died within 3 months of baseline. Seropositivity had an age-adjusted sdHR of 1.95 (95 % CI 1.02, 3.71) for RA flare compared to seronegativity, accounting for competing risk of death. Otherwise, no baseline factors were associated with RA flare, including cancer type, disease activity, RA duration, and deformities. 9/46 (20 %) patients had their ICI discontinued/paused due to RA flares. In the landmark analysis among 79 patients who survived at least 3 months, RA flare in the first 3 months was not associated with lower mortality (adjusted HR 1.24, 95 % CI 0.71, 2.16) compared to no RA flare.

CONCLUSION

Among patients with pre-existing RA, few changed immunomodulator medications in anticipation of starting ICI, but RA flares occurred in nearly half. RA flares were mostly mild and treated with typical therapies. Seropositivity was associated with RA flare risk. A minority had severe RA flares requiring disruption of ICI, and RA flares were not associated with mortality.

Comparison of efficacy discrepancy between early-phase clinical trials and phase III trials of PD-1/PD-L1 inhibitors

BACKGROUND

Phase III clinical trials are pivotal for evaluating therapeutics, yet a concerning failure rate has been documented, particularly impacting oncology where accelerated approvals of immunotherapies are common. These failures are predominantly attributed to a lack of therapeutic efficacy, indicating overestimation of results from phase II studies. Our research aims to systematically assess overestimation in early-phase trials involving programmed cell death-1 (PD-1)/programmed cell death-ligand 1(PD-L1) inhibitors compared with phase III trials and identify contributing factors.

METHODS

We matched 51 pairs of early-phase and phase III clinical trials from a pool of over 9,600 PD-1/PD-L1 inhibitor trials. The matching criteria included identical treatment regimens, cancer types, treatment lines, and biomarker enrichment strategies. To assess overestimation, we compared the overall response rates (ORR) between early-phase and phase III trials. We established independent variables related to eligibility criteria, and trial design features of participants to analyze the factors influencing the observed discrepancy in efficacy between the two phases through univariable and multivariable logistic analyses.

RESULT

Early-phase trial outcomes systematically overestimated the subsequent phase III results, yielding an odds ratio (OR) comparing ORR in early-phase versus phase III: 1.66 (95% CI: 1.43 to 1.92, p<0.05). This trend of inflated ORR was consistent across trials testing PD-1/PD-L1 monotherapies and combination therapies involving PD-1/PD-L1. Among the examined factors, the exclusion of patients with autoimmune diseases was significantly associated with the disparity in efficacy between early-phase trials and phase III trials (p=0.023). We calculated a Ward statistic of 2.27 to validate the effectiveness of the model.

CONCLUSION

These findings underscore the tendency of overestimation of efficacy in early-phase trials involving immunotherapies. The observed differences could be attributed to variations in the inclusion of patients with autoimmune disorders in early-phase trials. These insights have the potential to inform stakeholders in the future development of cancer immunotherapies.

Predictive Factors in Metastatic Melanoma Treated with Immune Checkpoint Inhibitors: From Clinical Practice to Future Perspective

The introduction of immunotherapy revolutionized the treatment landscape in metastatic melanoma. Despite the impressive results associated with immune checkpoint inhibitors (ICIs), only a portion of patients obtain a response to this treatment. In this scenario, the research of predictive factors is fundamental to identify patients who may have a response and to exclude patients with a low possibility to respond. These factors can be host-associated, immune system activation-related, and tumor-related. Patient-related factors can vary from data obtained by medical history (performance status, age, sex, body mass index, concomitant medications, and comorbidities) to analysis of the gut microbiome from fecal samples. Tumor-related factors can reflect tumor burden (metastatic sites, lactate dehydrogenase, C-reactive protein, and circulating tumor DNA) or can derive from the analysis of tumor samples (driver mutations, tumor-infiltrating lymphocytes, and myeloid cells). Biomarkers evaluating the immune system activation, such as IFN-gamma gene expression profile and analysis of circulating immune cell subsets, have emerged in recent years as significantly correlated with response to ICIs. In this manuscript, we critically reviewed the most updated literature data on the landscape of predictive factors in metastatic melanoma treated with ICIs. We focus on the principal limits and potentiality of different methods, shedding light on the more promising biomarkers.

Immune Checkpoint Inhibitors in Advanced Cutaneous Squamous Cell Carcinoma: Real-World Experience from a Canadian Comprehensive Cancer Centre

Immune checkpoint inhibitors (ICI) cemiplimab and pembrolizumab have revolutionized the treatment of advanced cutaneous squamous cell carcinoma (cSCC). We aimed to evaluate the effectiveness and safety of ICI in a real-world cSCC population, including patients with conditions that would exclude clinical trial participation. In this single-center, retrospective cohort study, we included all non-trial patients with advanced cSCC treated with ICI between 2017 and 2022. We evaluated investigator-assessed best overall response (BOR) and immune-related adverse events (irAEs). We correlated survival outcomes with age, performance status, immune status and irAEs. Of the 36 patients identified, the best overall response (BOR) to ICI was a partial response (PR) in 41.7%, a complete response (CR) in 27.8%, and stable disease in (SD) 13.9%. The progression-free survival (PFS) rate for 1 year was 58.1%; the median PFS was 21.3 months (95% CI 6.4-NE). The 1-year overall survival (OS) was 76.7%, and the median OS was 38.6 months (95% CI 25.4-NE). Immune-compromised patients, ECOG performance 2-3, and age ≥ 75 years were not significantly associated with PFS or OS. IrAE grades 3-4 were seen in 13.9% of patients. In our Canadian experience with real-world patients, ICI was an effective and safe treatment for advanced cSCC patients. Patients achieved great benefits with ICI regardless of age, immune status or ECOG performance status. We acknowledge the small sample size and retrospective methodology as the main limitations of our study.