Impact of clinicopathological characteristics on survival in patients treated with immune checkpoint inhibitors for metastatic melanoma

Intermediate endpoints as surrogates for outcomes in cancer immunotherapy: a systematic review and meta-analysis of phase 3 trials

Background

Cancer immunotherapy shows unique efficacy kinetics that differs from conventional treatment. These characteristics may lead to the prolongation of trial duration, hence reliable surrogate endpoints are urgently needed. We aimed to systematically evaluate the study-level performance of commonly reported intermediate clinical endpoints for surrogacy in cancer immunotherapy.

Methods

We searched the Embase, PubMed, and Cochrane databases, between database inception and October 18, 2022, for phase 3 randomised trials investigating the efficacy of immunotherapy in patients with advanced solid tumours. An updated search was done on July, 15, 2023. No language restrictions were used. Eligible trials had to set overall survival (OS) as the primary or co-primary endpoint and report at least one intermediate clinical endpoint including objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and 1-year overall survival. Other key inclusion and exclusion criteria included: (1) adult patients (>18 years old) with advanced solid tumour; (2) no immunotherapy conducted in the control arms; (3) follow-up is long enough to achieve OS; (4) data should be public available. A two-stage meta-analytic approach was conducted to evaluate the magnitude of the association between these intermediate endpoints and OS. A surrogate was identified if the coefficient of determination (R2) was 0.7 or greater. Leave-one-out cross-validation and pre-defined subgroup analysis were conducted to examine the heterogeneity. Potential publication bias was evaluated using the Egger's and Begg's tests. This trial was registered with PROSPERO, number CRD42022381648.

Findings

52,342 patients with 15 types of tumours from 77 phase 3 studies were included. ORR (R2 = 0.11; 95% CI, 0.00-0.24), DCR (R2 = 0.01; 95% CI, 0.00-0.01), and PFS (R2 = 0.40; 95% CI, 0.23-0.56) showed weak associations with OS. However, a strong correlation was observed between 1-year survival and clinical outcome (R2 = 0.74; 95% CI, 0.64-0.83). These associations remained relatively consistent across pre-defined subgroups stratified based on tumour types, masking methods, line of treatments, drug targets, treatment strategies, and follow-up durations. No significant heterogeneities or publication bias were identified.

Interpretation

1-year milestone survival was the only identified surrogacy endpoint for outcomes in cancer immunotherapy. Ongoing investigations and development of new endpoints and incorporation of biomarkers are needed to identify potential surrogate markers that can be more robust than 1-year survival. This work may provide important references in assisting the design and interpretation of future clinical trials, and constitute complementary information in drafting clinical practice guidelines.

Funding

None.

Clinical Models to Define Response and Survival With Anti-PD-1 Antibodies Alone or Combined With Ipilimumab in Metastatic Melanoma

PURPOSE

Currently, there are no robust biomarkers that predict immunotherapy outcomes in metastatic melanoma. We sought to build multivariable predictive models for response and survival to anti-programmed cell death protein 1 (anti-PD-1) monotherapy or in combination with anticytotoxic T-cell lymphocyte-4 (ipilimumab [IPI]; anti-PD-1 ± IPI) by including routine clinical data available at the point of treatment initiation.

METHODS

One thousand six hundred forty-four patients with metastatic melanoma treated with anti-PD-1 ± IPI at 16 centers from Australia, the United States, and Europe were included. Demographics, disease characteristics, and baseline blood parameters were analyzed. The end points of this study were objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). The final predictive models for ORR, PFS, and OS were determined through penalized regression methodology (least absolute shrinkage and selection operator method) to select the most significant predictors for all three outcomes (discovery cohort, N = 633). Each model was validated internally and externally in two independent cohorts (validation-1 [N = 419] and validation-2 [N = 592]) and nomograms were created.

RESULTS

The final model for predicting ORR (area under the curve [AUC] = 0.71) in immunotherapy-treated patients included the following clinical parameters: Eastern Cooperative Oncology Group Performance Status, presence/absence of liver and lung metastases, serum lactate dehydrogenase, blood neutrophil-lymphocyte ratio, therapy (monotherapy/combination), and line of treatment. The final predictive models for PFS (AUC = 0.68) and OS (AUC = 0.77) included the same variables as those in the ORR model (except for presence/absence of lung metastases), and included presence/absence of brain metastases and blood hemoglobin. Nomogram calculators were developed from the clinical models to predict outcomes for patients with metastatic melanoma treated with anti-PD-1 ± IPI.

CONCLUSION

Newly developed combinations of routinely collected baseline clinical factors predict the response and survival outcomes of patients with metastatic melanoma treated with immunotherapy and may serve as valuable tools for clinical decision making.

Efficacy and safety profile of avelumab monotherapy

Avelumab can kill cancer cells through immune checkpoint inhibition and antibody-dependent cell-mediated cytotoxicity (ADCC). Here, we analyzed the clinical efficacy and adverse events (AEs) in 3935 cancer patients from 21 trials. Compared with conventional treatment, avelumab monotherapy was associated with more tumor responses and less AEs. The pooled objective response rate was 14.18 % (95 % CI, 10.68 %-18.08 %). More PD-L1 positive patients responded to avelumab monotherapy compared to PD-L1 negative patients. The overall incidence was 73.78 % for all-grade treatment-related AE (TRAE), 14.44 % for high-grade TRAE, 6.07 % for serious adverse event, 0.44 % for fatal adverse event, 17.86 % for all-grade immune-related AE (irAE), and 3.22 % for high-grade irAE. In summary, avelumab monotherapy presents an active anti-tumor activity, shows no sign of increased toxicity due to the ADCC. These characteristics provide rational for further application of avelumab in cancer treatment.

Clinical Categorization Algorithm (CLICAL) and Machine Learning Approach (SRF-CLICAL) to Predict Clinical Benefit to Immunotherapy in Metastatic Melanoma Patients: Real-World Evidence from the Istituto Nazionale Tumori IRCCS Fondazione Pascale, Napoli, Italy

The real-life application of immune checkpoint inhibitors (ICIs) may yield different outcomes compared to the benefit presented in clinical trials. For this reason, there is a need to define the group of patients that may benefit from treatment. We retrospectively investigated 578 metastatic melanoma patients treated with ICIs at the Istituto Nazionale Tumori IRCCS Fondazione "G. Pascale" of Napoli, Italy (INT-NA). To compare patients' clinical variables (i.e., age, lactate dehydrogenase (LDH), neutrophil-lymphocyte ratio (NLR), eosinophil, BRAF status, previous treatment) and their predictive and prognostic power in a comprehensive, non-hierarchical manner, a clinical categorization algorithm (CLICAL) was defined and validated by the application of a machine learning algorithm-survival random forest (SRF-CLICAL). The comprehensive analysis of the clinical parameters by log risk-based algorithms resulted in predictive signatures that could identify groups of patients with great benefit or not, regardless of the ICI received. From a real-life retrospective analysis of metastatic melanoma patients, we generated and validated an algorithm based on machine learning that could assist with the clinical decision of whether or not to apply ICI therapy by defining five signatures of predictability with 95% accuracy.

Complete response to immunotherapy in a nonagenarian patient with metastatic melanoma

Despite the increasing incidence of metastatic melanoma in the older population, there are relatively limited data for those older than 75 years of age. Elderly patients are often under-represented in clinical trials. In addition, elderly patients in trials often have a lower Eastern Cooperative Oncology Group score and fewer comorbidities and may thus not truly reflect the realities of day-to-day clinical practice. We present a case of a 95-year-old woman who had extensive and unresectable subcutaneous and dermal deposits of metastatic melanoma of her right leg, which caused oedema and reduced mobility. She was treated concurrently with pembrolizumab and radiotherapy to her leg lesions of melanoma. She has had an excellent response to treatment, with complete resolution of the subcutaneous and dermal metastatic deposits and has not developed any immune-related toxicities. Our experience demonstrates that anti-programmed-death-receptor-1 therapy can be given safely and effectively even in very elderly metastatic melanoma patients.

Impact of modern systemic therapies and clinical markers on treatment outcome for metastatic melanoma in a real-world setting

BACKGROUND

The survival in metastatic melanoma has dramatically improved after the introduction of immune checkpoint- (ICIs) and MAPKinase inhibitors (MAPKis).

OBJECTIVE

Our aim was to describe therapy response and survival in a real-world population as well as to assess the associations between clinical variables and therapy outcome for patients with metastatic melanoma receiving first-line ICIs or MAPKis.

METHODS

A total of 252 patients with metastatic (stage IV) melanoma were prospectively followed between 1 January 2010 and 3 December 2017 with follow-up until 31 March 2019, at the Karolinska University Hospital, Sweden. Hazard ratios (HRs) for progression-free survival (PFS) and overall survival (OS) were analysed with Cox regression, and logistic regression was used to estimate odds ratios (ORs) for therapy response.

RESULTS

Patients receiving ICIs (n = 138) experienced longer PFS compared to patients that received MAPKis (n = 114; median PFS for ICIs was 6.8 months, and median PFS for MAPKis was 5.3 months). In the multivariable analyses of clinical markers, increasing M-stage (OR 0.65; 95% CI 0.45-0.94; P = 0.022) and male sex (OR 0.41; 95% CI 0.19-0.90; P = 0.027) were significantly associated with lower response to ICIs. Lower baseline albumin levels (OR 0.90; 95% CI 0.83-0.98; P = 0.019) and male sex (OR 0.33; 95% CI 0.12-0.93; P = 0.036) were related with lower response to MAPKis. For ICIs, increasing M-stage (HR 1.34; 95% CI 1.07-1.68; P = 0.010), increasing LDH (HR 1.73; 95% CI 1.19-2.50; P = 0.004) and decreasing albumin (HR 1.06; 95% CI 1.01-1.10; P = 0.011) were significantly associated lower PFS in the adjusted model. The corresponding markers for MAPKis were increasing LDH (HR 1.44; 95% CI 1.08-1.92; P = 0.013) and decreasing albumin (HR 1.05; 95% CI 1.02-1.09; P = 0.005) for PFS.

CONCLUSION

ICIs and MAPKis were effective in this real-world population, and we could confirm the importance of previously reported clinical prognostic markers. Albumin values may be associated with therapy outcome but need further validation.

Fatal adverse events associated with programmed cell death protein 1 or programmed cell death-ligand 1 monotherapy in cancer

Background:

The introduction of antibodies targeting programmed cell death protein 1 (PD-1) and programmed cell death-ligand 1 (PD-L1) into clinical practice has had a revolutionary effect on cancer treatment. However, the incidence and risk of fatal adverse events (FAEs) following PD-1/PD-L1 inhibitor administration are controversial.

Methods:

We performed a systematic search for randomized controlled trials (RCTs) of PD-1/PD-L1 inhibitors (atezolizumab, avelumab, durvalumab, nivolumab, and pembrolizumab) in Embase, PubMed, the Cochrane database, and abstracts presented at American Society of Clinical Oncology and European Society of Medical Oncology from inception to July 2018. FAEs were extracted from each study and pooled to calculate overall incidence and odds ratios (ORs).

Results:

In total, 20 RCTs involving 12,398 patients with solid tumors were included in this study. The overall incidence of FAEs with PD-1/PD-L1 inhibitors was 0.43% [95% confidence interval (CI), 0.25–0.66%]. However, the incidences of FAEs varied significantly by tumor type and median follow-up time. Compared with conventional agents, the application of PD-1/PD-L1 inhibitors significantly reduced the risk of FAEs (OR, 0.56; 95% CI, 0.35–0.89; p = 0.015). Moreover, trial sequential analysis confirmed that our results were solid and reliable; further studies were unlikely to alter this conclusion. FAEs occurred dispersed in major organ systems, with the most common mortalities appearing in the respiratory system (46.2%).

Conclusions:

Compared with conventional treatment, PD-1/PD-L1 blockade monotherapy is associated with a significantly reduced risk of mortality in patients with solid tumors.

Characterization of patients with metastatic non-small-cell lung cancer obtaining long-term benefit from immunotherapy

Aim: A minority of patients gains advantage from immunotherapy (IO). Predictive variables of long-term benefit (LTB) are incompletely understood. Materials & methods: We retrospectively collected data about metastatic non-small-cell lung cancer patients treated with IO from April 2013 to July 2017. We defined LTB to IO as complete response (CR), partial response (PR) or disease stability as best response and maintaining it for ≥12 months. Results: Thirty-five of the 147 patients had LTB. More LTB patients than controls showed CR/PR as first and best response to IO. Only CR/PR as best response to IO retained association to LTB at multivariate analyses. Conclusion: Objective response appears as a central factor for LTB from IO.