Crossover and rechallenge with pembrolizumab in recurrent patients from the EORTC 1325-MG/Keynote-054 phase III trial, pembrolizumab versus placebo after complete resection of high-risk stage III melanoma

BACKGROUND

In the phase III double-blind European Organisation for Research and Treatment of Cancer 1325/KEYNOTE-054 trial, pembrolizumab improved recurrence-free and distant metastasis-free survival in patients with stage III cutaneous melanoma with complete resection of lymph nodes. In the pembrolizumab group, the incidence of grade I-V and of grade III-V immune-related adverse events (irAEs) was 37% and 7%, respectively.

METHODS

Patients were randomised to receive intravenous (i.v.) pembrolizumab 200 mg (N = 514) or placebo (N = 505) every 3 weeks, up to 1 year. On recurrence, patients could enter part 2 of the study: pembrolizumab 200 mg i.v. every 3 weeks up to 2 years, for crossover (those who received placebo) or rechallenge (those who had recurrence ≥6 months after completing 1-year adjuvant pembrolizumab therapy). For these patients, we present the safety profile and efficacy outcomes.

RESULTS

At the clinical cut-off (16-Oct-2020), in the placebo group, 298 patients had a disease recurrence, in which 155 (52%) crossed over ('crossover'). In the pembrolizumab group, 297 patients completed the 1-year treatment period; 47 had a recurrence ≥6 months later, in which 20 (43%) entered the rechallenge part 2 ('rechallenge'). In the crossover group, the median progression-free survival (PFS) was 8.5 months (95% confidence interval [CI] 5.7-15.2) and the 3-year PFS rate was 32% (95% CI 25-40%). Among 80 patients with stage IV evaluable disease, 31 (39%) had an objective response: 14 (18%) patients with complete response (CR) and 17 (21%) patients with partial response. The 2-year PFS rate from response was 69% (95% CI 48-83%). In the rechallenge group, the median PFS was 4.1 months (95% CI 2.6-NE). Among 9 patients with stage IV evaluable disease, 1 had an objective response (CR). Among the 175 patients, 51 (29%) had a grade I-IV irAE and 11 (6%) had a grade III-IV irAE.

CONCLUSIONS

Pembrolizumab treatment after crossover yielded an overall 3-year PFS rate of 32% and a 39% ORR in evaluable patients, but the efficacy (11% ORR) was lower in those rechallenged.

Anti-PD-1 and Anti-PD-L1 in Head and Neck Cancer: A Network Meta-Analysis

Objective

The monoclonal antibodies anti-programmed death protein-1 (anti-PD-1) nivolumab and pembrolizumab are the first immune checkpoint inhibitors (ICIs) approved for treatment of recurrent/metastatic head and neck carcinoma R/M HNSCC in first line and in platinum refractory disease. This network meta-analysis aims to investigate the efficacy of anti-PD-1- vs anti-PD-L1-based therapy in R/M HNSCC cancer patients through a systematic review of the literature to provide support for evidence-based treatment decisions. In particular, the effectiveness of ICIs for R/M HNSCC is analyzed according to the different mechanisms of action of the check-points inhibitory drugs in different subgroups of patients.

Methods

We did a systematic literature review and network meta-analysis (NMA) of randomized controlled trials (RCTs) in PubMed, ClinicalTrials.gov, Embase, Medline, the Cochrane Central Register of Controlled Trials, Web of Science. Our search identified a total of five randomized controlled trials: Keynote 040, Keynote 048, Eagle, Condor, Checkmate 141. These trials included 3001 patients. Treatment was sub-categorized into PD-L1-based, PD-1-based, and standard chemotherapy. Treatments were indirectly compared with anti-PD-L1-based therapy.

Results

The network meta-analysis demonstrated no significant differences in OS between different subgroups except for the metastatic patients in which anti-PD-1-based therapy was associated with significantly less risk of death. Furthermore, anti-PD-1-based therapy appeared to be effective in smoker patients and in human papilloma-negative (HPV) patients. Conversely, anti-PD-L1-based therapy seems to be better efficient in female patients, in locally recurrent setting and in HPV positive patients.

Conclusion

This is the first NMA study that aimed to indirectly compare anti-PD-1- and anti-PD-L1-based therapy in HNSCC patients. The results of our NMA could help define a profile of patient responder or resistant to specific classes of immune drugs and can be used to guide/design future studies in the novel scenario of precision immune-oncology.

Cutaneous adverse reactions to anti-PD-1 treatment-A systematic review

The use of the humanized monoclonal anti-programmed cell death 1 antibodies pembrolizumab and nivolumab as potent anticancer therapies is rapidly increasing. However, since their approval, numerous cases of cutaneous reactions have been reported. Cutaneous adverse reactions to these agents have yet to be fully characterized and range from nonspecific eruptions to recognizable skin manifestations, which may be localized and vary from mild to life threatening. This systematic review article provides an overview of the various adverse cutaneous reactions to pembrolizumab and nivolumab therapy and offers suggestions for their management.

Impaired Tumor-Infiltrating T Cells in Patients with Chronic Obstructive Pulmonary Disease Impact Lung Cancer Response to PD-1 Blockade

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) have a higher prevalence of lung cancer. The chronic inflammation associated with COPD probably promotes the earliest stages of carcinogenesis. However, once tumors have progressed to malignancy, the impact of COPD on the tumor immune microenvironment remains poorly defined, and its effects on immune-checkpoint blockers' efficacy are still unknown.

OBJECTIVES

To study the impact of COPD on the immune contexture of non-small cell lung cancer.

METHODS

We performed in-depth immune profiling of lung tumors by immunohistochemistry and we determined its impact on patient survival (n = 435). Tumor-infiltrating T lymphocyte (TIL) exhaustion by flow cytometry (n = 50) was also investigated. The effectiveness of an anti-PD-1 (programmed cell death-1) treatment (nivolumab) was evaluated in 39 patients with advanced-stage non-small cell lung cancer. All data were analyzed according to patient COPD status.

MEASUREMENTS AND MAIN RESULTS

Remarkably, COPD severity is positively correlated with the coexpression of PD-1/TIM-3 (T-cell immunoglobulin and mucin domain-containing molecule-3) by CD8 T cells. In agreement, we observed a loss of CD8 T cell-associated favorable clinical outcome in COPD⁺ patients. Interestingly, a negative prognostic value of PD-L1 (programmed cell death ligand 1) expression by tumor cells was observed only in highly CD8 T cell-infiltrated tumors of COPD⁺ patients. Finally, data obtained on 39 patients with advanced-stage non-small cell lung cancer treated by an anti-PD-1 antibody showed longer progression-free survival in COPD⁺ patients, and also that the association between the severity of smoking and the response to nivolumab was preferentially observed in COPD⁺ patients.

CONCLUSIONS

COPD is associated with an increased sensitivity of CD8 tumor-infiltrating T lymphocytes to immune escape mechanisms developed by tumors, thus suggesting a higher sensitivity to PD-1 blockade in patients with COPD.

Blocking IL-1β reverses the immunosuppression in mouse breast cancer and synergizes with anti-PD-1 for tumor abrogation

Interleukin-1β (IL-1β) is abundant in the tumor microenvironment, where this cytokine can promote tumor growth, but also antitumor activities. We studied IL-1β during early tumor progression using a model of orthotopically introduced 4T1 breast cancer cells. Whereas there is tumor progression and spontaneous metastasis in wild-type (WT) mice, in IL-1β-deficient mice, tumors begin to grow but subsequently regress. This change is due to recruitment and differentiation of inflammatory monocytes in the tumor microenvironment. In WT mice, macrophages heavily infiltrate tumors, but in IL-1β-deficient mice, low levels of the chemokine CCL2 hamper recruitment of monocytes and, together with low levels of colony-stimulating factor-1 (CSF-1), inhibit their differentiation into macrophages. The low levels of macrophages in IL-1β-deficient mice result in a relatively high percentage of CD11b⁺ dendritic cells (DCs) in the tumors. In WT mice, IL-10 secretion from macrophages is dominant and induces immunosuppression and tumor progression; in contrast, in IL-1β-deficient mice, IL-12 secretion by CD11b⁺ DCs prevails and supports antitumor immunity. The antitumor immunity in IL-1β-deficient mice includes activated CD8⁺ lymphocytes expressing IFN-γ, TNF-α, and granzyme B; these cells infiltrate tumors and induce regression. WT mice with 4T1 tumors were treated with either anti-IL-1β or anti-PD-1 Abs, each of which resulted in partial growth inhibition. However, treating mice first with anti-IL-1β Abs followed by anti-PD-1 Abs completely abrogated tumor progression. These data define microenvironmental IL-1β as a master cytokine in tumor progression. In addition to reducing tumor progression, blocking IL-1β facilitates checkpoint inhibition.

Anti-PD-1/anti-CTLA-4 efficacy in melanoma brain metastases depends on extracranial disease and augmentation of CD8+ T cell trafficking

Inhibition of immune checkpoints programmed death 1 (PD-1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) on T cells results in durable antitumor activity in melanoma patients. Despite high frequency of melanoma brain metastases (BrM) and associated poor prognosis, the activity and mechanisms of immune checkpoint inhibitors (ICI) in metastatic tumors that develop within the "immune specialized" brain microenvironment, remain elusive. We established a melanoma tumor transplantation model with intracranial plus extracranial (subcutaneous) tumor, mimicking the clinically observed coexistence of metastases inside and outside the brain. Strikingly, intracranial ICI efficacy was observed only when extracranial tumor was present. Extracranial tumor was also required for ICI-induced increase in CD8+ T cells, macrophages, and microglia in brain tumors, and for up-regulation of immune-regulatory genes. Combined PD-1/CTLA-4 blockade had a superior intracranial efficacy over the two monotherapies. Cell depletion studies revealed that NK cells and CD8+ T cells were required for intracranial anti-PD-1/anti-CTLA-4 efficacy. Rather than enhancing CD8+ T cell activation and expansion within intracranial tumors, PD-1/CTLA-4 blockade dramatically (∼14-fold) increased the trafficking of CD8+ T cells to the brain. This was mainly through the peripheral expansion of homing-competent effector CD8+ T cells and potentially further enhanced through up-regulation of T cell entry receptors intercellular adhesion molecule 1 and vascular adhesion molecule 1 on tumor vasculature. Our study indicates that extracranial activation/release of CD8+ T cells from PD-1/CTLA-4 inhibition and potentiation of their recruitment to the brain are paramount to the intracranial anti-PD-1/anti-CTLA-4 activity, suggesting augmentation of these processes as an immune therapy-enhancing strategy in metastatic brain cancer.