Baseline and early functional immune response is associated with subsequent clinical outcomes of PD-1 inhibition therapy in metastatic melanoma patients

Abstract

Background: Despite significant progress with antiprogrammed cell death protein 1 (PD-1) therapy, a substantial fraction of metastatic melanoma patients show upfront therapy resistance. Biomarkers for outcome are missing and the association of baseline immune function and clinical outcome remains to be determined. We assessed the in vitro nonspecific stimulation of immune response at baseline and during anti-PD-1 therapy for metastatic melanoma.

Methods: Previously untreated metastatic melanoma patients received nivolumab and radiotherapy as part of the multicentric phase II trial NIRVANA (NCT02799901). The levels of Th1, Th2 and Th17 cytokines on in vitro non-specific stimulation of innate and adaptive immune cells were measured in patient sera before treatment, and at week 2 and week 6 after the beginning of the treatment, and correlated with tumorous response, progression-free survival (PFS) and occurrence of immune-related adverse events (irAEs). The results in melanoma patients were compared with those of a cohort of 9 sex and age-matched healthy donors.

Results: Seventeen patients were enrolled in this ancillary study. Median follow-up was 16 months (2.2-28.4). The 12-month PFS rate was 67.7%. The incidence of irAEs of any grade was 58.8%. Without in vitro stimulation no differences in cytokines levels were observed between responders and non-responders. On in vitro stimulation, metastatic patients had lower Th1 cytokine levels than healthy donors at baseline for tumor necrosis factor-α and interferon-γ (IFN-γ) (1136 pg/mL vs 5558 pg/mL, p<0.0001; and 3894 pg/mL vs 17 129 pg/mL, p=0.02, respectively). Responders exhibited increasing cytokine levels from baseline to week 6. Non-responders had lower interleukin 17A (IL-17A) levels at baseline than responders (7 pg/mL vs 32 pg/mL, p=0.03), and lower IFN-γ levels at week 6 (3.3 ng/mL vs 14.5 ng/mL, p=0.03). A lower level of IL-17A at week 2 and a lower level of IFN-γ at week 6 correlated with worse PFS (p=0.04 and p=0.04 respectively). At baseline, patients who developed irAEs had higher IL-6 levels (19.3 ng/mL vs 9.2 ng/mL, p=0.03) and higher IL-17A levels (52.5 pg/mL vs 2.5 pg/mL, p=0.009) than those without irAEs.

Conclusions: Our findings indicate that cytokine levels after in vitro non-specific stimulation could be a promising biomarker to predict the outcome of PD-1 inhibition therapy.

Keywords: cellular; cytokines; immunity; immunocompetence; immunotherapy; programmed cell death 1 receptor.

Conflict of interest statement

Competing interests: None declared.

© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Effect of in vitro stimulation on the baseline levels of IL-1β, IL-4, IL-5, IL-6, IL-8, IL-12p70, IL-17, IFN-γ and TNF-α in the seven first patients included. before stimulation, cytokines are mostly undetectable. IFN-γ, interferon-γ; IL-8, interleukin 8; TNF-α, tumor necrosis factor-α.

Figure 2

Comparison of baseline cytokines levels after stimulation in the 17 melanoma patients and in 16 age-matched healthy donors, showing that melanoma patients have significantly lower Th1 cytokines levels (TNF-α and IFN- γ). IFN-γ, interferon-γ; IL-16, interleukin 16; TNF-α, tumor necrosis factor-α.

Figure 3

Cytokines levels of different immune pathways (Th1, Th2, Th17) after stimulation in responders and non-responders at baseline and during treatment with nivolumab (at week 2 and week 6). (A) IFN-γ levels in responders and non-responders at baseline and during treatment with nivolumab. IFN-γ levels become significantly higher in responders at week 6. (B) IL-2 levels in responders and non-responders at baseline and during treatment with nivolumab. Levels do not significantly differ between responders and non-responders. (C) Kaplan-Meier curves showing progression-free survival in patients with high and low IFN-γ levels at week 6. High IFN-γ levels at week 6 are associated with better progression free survival. (D) IL-17A levels in responders and non-responders at baseline and during treatment with nivolumab. IL-17A levels are significantly higher in responders at baseline as well as week 2 and week 6. (E) IL-6 levels in responders and non-responders at baseline and during treatment with nivolumab. Levels do not significantly differ between responders and non-responders. (F) Kaplan-Meier curves showing progression free survival in patients with high and low IL-17A levels at week 2. High IL-17A levels at week 2 are associated with better progression free survival. (G) IL-4 levels in responders and non-responders at baseline and during treatment with nivolumab. IL-4 levels become significantly higher in responders at week 2. (H) IL-5 levels in responders and non-responders at baseline and during treatment with nivolumab. IL-5 levels become significantly higher in responders at week 2. (I) Kaplan-Meier curves showing progression free survival in patients with high and low IL-4 levels at week 2. High IL-4 levels at week 2 are associated with better progression-free survival. IFN-γ, interferon-γ; IL-6, interleukin 6; TNF-α, tumor necrosis factor-α.

Figure 4

Cytokines (IL-17A, IL-6, IL-4, IFN-γ) levels after stimulation in patients with and without immune-related adverse events (irAE) at baseline and during treatment with nivolumab (at week 2 and week 6). IL-17A and IL-6 levels are consistently higher in patients with immune-related adverse events at each point, even at baseline. IL-4 and IFN-γ levels become both significantly higher in patients with immune related adverse events at week 2 and week 6. IFN-γ, interferon-γ; IL-6, interleukin 6; TNF-α, tumor necrosis factor-α.