A phase II study of retifanlimab, a humanized anti-PD-1 monoclonal antibody, in patients with solid tumors (POD1UM-203).

BACKGROUND: POD1UM-203, an open-label, multicenter, phase II study, evaluated retifanlimab, a humanized monoclonal antibody targeting programmed cell death protein-1 (PD-1) in patients with selected solid tumors where immune checkpoint inhibitor therapies have previously shown efficacy. PATIENTS AND METHODS: Eligible patients (≥18 years) had measurable disease and included unresectable or metastatic melanoma, treatment-naive metastatic non-small-cell lung cancer (NSCLC) with high programmed death-ligand 1 (PD-L1) expression (tumor proportion score ≥50%), cisplatin-ineligible locally advanced/metastatic urothelial carcinoma (UC) with PD-L1 expression (combined positive score ≥10%), or treatment-naive locally advanced/metastatic clear-cell renal cell carcinoma (RCC). Retifanlimab 500 mg was administered intravenously every 4 weeks as a 30-min infusion. The primary endpoint was investigator-assessed overall response rate. RESULTS: Overall, 121 patients (35 melanoma, 23 NSCLC, 29 UC, 34 RCC) were enrolled and treated. The overall response rate [95% confidence interval (CI)] was 40.0% (23.9-57.9) in the melanoma cohort, 34.8% (16.4-57.3) in the NSCLC cohort, 37.9% (20.7-57.7) in the UC cohort, and 23.5% (10.7-41.2) in the RCC cohort. Median duration of response was 11.5 months (95% CI 2.2-not reached) in the UC cohort, and was not reached in the other cohorts. Retifanlimab safety was consistent with previous experience for PD-(L)1 inhibitors. CONCLUSIONS: Retifanlimab demonstrated durable antitumor activity in patients with melanoma, NSCLC, UC, or RCC. The efficacy and safety of retifanlimab were as expected for a PD-(L)1 inhibitor. These data support further study of retifanlimab in solid tumors.

Immune checkpoint inhibitor associated vitiligo and its impact on survival in patients with metastatic melanoma: an Italian Melanoma Intergroup study.

BACKGROUND: Checkpoint inhibitors in melanoma can lead to self-immune side-effects such as vitiligo-like depigmentation (VLD). Beyond the reported association with favorable prognosis, there are limited data regarding VLD patient features and their echo on the therapeutic outcomes. METHODS: To assess the association between VLD and a series of clinical and biological features as well as therapeutic outcomes, we built an observational cohort study by recruiting patients who developed VLD during checkpoint inhibitors. RESULTS: A total of 148 patients from 15 centers (101 men, median age 66 years, BRAF mutated 23%, M1c 42%, Eastern Cooperative Oncology Group (ECOG) status 0/1 99%, normal lactate dehydrogenase 74%) were enrolled. VLD was induced by ipilimumab, programmed cell death-1 (PD-1) inhibitors, and their combination in 32%, 56%, and 12%, respectively. The median onset was 26 weeks and it was associated with other skin and nonskin toxicities in 27% and 28%, respectively. After 3 years of VLD onset, 52% (95% confidence interval 39% to 63%) were progression free and 82% (95% confidence interval 70% to 89%) were still alive. The overall response rate was 73% with 26% complete response. Univariable analysis indicated that BRAF V600 mutation was associated with a better overall survival (P = 0.028), while in multivariable analysis a longer progression-free survival was associated with BRAF V600 (P = 0.093), female sex (P = 0.008), and M stage other than 1a (P = 0.024). When VLD occurred, there was a significant decrease of white blood cell (WBC) count (P = 0.05) and derived WBC-to-lymphocytes ratio (dWLR; P = 0.003). A lower monocyte count (P = 0.02) and dWLR (P = 0.01) were also reported in responder patients. CONCLUSIONS: Among VLD population, some features might help to identify patients with an effective response to immunotherapy, allowing clinicians to make more appropriate choices in terms of therapeutic options and duration.

Baseline serum TSH levels predict the absence of thyroid dysfunction in cancer patients treated with immunotherapy.

PURPOSE: Immunotherapy against immune checkpoints has significantly improved survival both in metastatic and adjuvant setting in several types of cancers. Thyroid dysfunction is the most common endocrine adverse event reported. Patients who are at risk of developing thyroid dysfunction remain to be defined. We aimed to identify predictive factors for the development of thyroid dysfunction during immunotherapy. METHODS: This is a retrospective study including a total of 68 patients who were treated with immune checkpoint inhibitors (ICIs) for metastatic or unresectable advanced cancers. The majority of patients were treated with anti-PD1 drugs in monotherapy or in combination with anti-CTLA4 inhibitors. Thyroid function and anti-thyroid antibodies, before starting immunotherapy and during treatment, were evaluated. Thyroid ultrasound was also performed in a subgroup of patients at the time of enrolment in the study. RESULTS: Eleven out of 68 patients (16.1%) developed immune-related overt thyroid dysfunction. By ROC curve analysis, we found that a serum TSH cut-off of 1.72 mUI/l, at baseline, had a good diagnostic accuracy in identifying patients without overt thyroid dysfunction (NPV = 100%, p = 0.0029). At multivariate analysis, both TSH and positive anti-thyroid antibodies (ATAbs) levels, before ICIs treatment, were independently associated with the development of overt thyroid dysfunction during immunotherapy (p = 0.0001 and p = 0.009, respectively). CONCLUSIONS: Pre-treatment serum TSH and ATAbs levels may help to identify patients at high risk for primary thyroid dysfunction. Our study suggests guidance for an appropriate timely screening and for a tailored management of thyroid dysfunctions in patients treated with ICIs.

Prognostic impact of baseline tumour immune infiltrate on disease-free survival in patients with completely resected, BRAFv600 mutation-positive melanoma receiving adjuvant vemurafenib.

BACKGROUND: We conducted a retrospective exploratory analysis to evaluate the effects of baseline tumour immune infiltrate on disease-free survival (DFS) outcomes in patients with fully resected stage IIC-IIIC melanoma receiving adjuvant vemurafenib monotherapy or placebo in the BRIM8 study. PATIENTS AND METHODS: BRIM8 was a phase III, international, double-blind, randomised, placebo-controlled study. Eligible patients with BRAFV600 mutation-positive, completely resected melanoma were randomly assigned to oral vemurafenib (960 mg twice daily) or matching placebo for 52 weeks. The primary end point was DFS. The association of CD8+ T-cell infiltration and programmed death ligand 1 (PD-L1) expression with DFS, as measured by immunohistochemistry, was explored retrospectively. RESULTS: Four hundred ninety-eight patients were randomly assigned to receive adjuvant vemurafenib (n = 250) or placebo (n = 248); tumour samples were available for biomarker analysis for approximately 60% of patients. In the pooled biomarker population, placebo-treated patients with <1% CD8+ T cells in the tumour centre had shorter median DFS than those with ≥1% CD8+ T cells (7.7 versus 47.8 months). DFS benefit from vemurafenib versus placebo was greater in patients with <1% CD8+ T cells [hazard ratio (HR) 0.56; 95% confidence interval (CI) 0.34-0.92) than in patients with ≥1% CD8+ T cells (HR 0.77; 95% CI 0.48-1.22). Likewise, median DFS was shorter among placebo-treated patients with <5% versus ≥5% PD-L1+ immune cells (IC) in the tumour (7.2 versus 47.8 months). A greater DFS benefit with vemurafenib versus placebo was observed in patients with <5% PD-L1+IC (HR 0.36; 95% CI 0.24-0.56) than in patients with ≥5% PD-L1+IC (HR 0.99; 95% CI 0.58-1.69). CONCLUSIONS: The presence of CD8+ T cells and PD-L1+IC are favourable prognostic factors for DFS. Treatment with adjuvant vemurafenib may overcome the poor DFS prognosis associated with low CD8+ T-cell count or PD-L1 expression. CLINICALTRIALS. GOV IDENTIFIER: NCT01667419.

Predictors of responses to immune checkpoint blockade in advanced melanoma.

Immune checkpoint blockers (ICB) have become pivotal therapies in the clinical armamentarium against metastatic melanoma (MMel). Given the frequency of immune related adverse events and increasing use of ICB, predictors of response to CTLA-4 and/or PD-1 blockade represent unmet clinical needs. Using a systems biology-based approach to an assessment of 779 paired blood and tumor markers in 37 stage III MMel patients, we analyzed association between blood immune parameters and the functional immune reactivity of tumor-infiltrating cells after ex vivo exposure to ICB. Based on this assay, we retrospectively observed, in eight cohorts enrolling 190 MMel patients treated with ipilimumab, that PD-L1 expression on peripheral T cells was prognostic on overall and progression-free survival. Moreover, detectable CD137 on circulating CD8+ T cells was associated with the disease-free status of resected stage III MMel patients after adjuvant ipilimumab + nivolumab (but not nivolumab alone). These biomarkers should be validated in prospective trials in MMel.The clinical management of metastatic melanoma requires predictors of the response to checkpoint blockade. Here, the authors use immunological assays to identify potential prognostic/predictive biomarkers in circulating blood cells and in tumor-infiltrating lymphocytes from patients with resected stage III melanoma.

Antitumor activity of epigenetic immunomodulation combined with CTLA-4 blockade in syngeneic mouse models.

The multifaceted immunomodulatory activity of DNA hypomethylating agents improves immunogenicity and immune recognition of neoplastic cells; thus, we predicted they could be utilized to design new immunotherapeutic combinations in cancer. Testing this hypothesis, the antitumor efficacy of the DNA hypomethylating agent 5-aza-2'-deoxycytidine (5-AZA-CdR) combined with the anti-CTLA-4 monoclonal antibody (mAb) 9H10 in syngeneic transplantable murine models was investigated. Murine mammary carcinoma TS/A or mesothelioma AB1 cells were injected in BALB/c, athymic nude, and SCID/Beige mice that were treated with 5-AZA-CdR, mAb 9H10, or their combination. Tumor volumes were captured at different time-points; molecular and immunohistochemical assays investigated changes in neoplastic and normal tissues. A significant antitumor effect of 5-AZA-CdR combined with mAb 9H10 was found: compared to controls, a 77% (p < 0.01), 54% (p < 0.01) and 33% (p = 0.2) decrease in TS/A tumor growth was induced by 5-AZA-CdR combined with mAb 9H10, 5-AZA-CdR or mAb 9H10, respectively. These antitumor activities were confirmed utilizing the AB1 model. 5-AZA-CdR-based regimens induced a promoter-demethylation-sustained tumor expression of cancer testis antigens. MHC class I expression was up-regulated by 5-AZA-CdR. Antitumor efficacy of 5-AZA-CdR in athymic nude and SCID/Beige mice was not increased by mAb 9H10. In BALB/c mice, combined treatment induced the highest tumor infiltration by CD3+ lymphocytes, which included both CD8+ and CD4+ T cells; no such infiltrates were observed in normal tissues. This significant immune-related antitumor activity of 5-AZA-CdR combined with CTLA-4 blockade, demonstrated in highly aggressive mouse tumor models, provides a strong scientific rationale to implement epigenetically-based immunotherapies in cancer patients.

Baseline neutrophil-to-lymphocyte ratio is associated with outcome of ipilimumab-treated metastatic melanoma patients.

BACKGROUND: Ipilimumab improves the survival of metastatic melanoma patients. Despite documented, durable objective responses, a significant number of patients fails to benefit from treatment. The aim of this study was to identify an upfront marker for treatment benefit. METHODS: A total of 187 metastatic melanoma patients treated in three Italian Institutions with 3 mg kg(-1) ipilimumab, and 27 patients treated with 10 mg kg(-1) ipilimumab, were evaluated. Neutrophil-to-lymphocyte ratio (NLR) was calculated from pre-therapy full blood counts. Progression-free survival (PFS) and overall survival (OS) were assessed using the Kaplan-Meier method, and multivariate Cox models were applied, adjusting for confounders and other prognostic factors. RESULTS: In the training cohort of 69 patients treated at European Institute of Oncology, pre-therapy NLR was identified as the strongest and independent marker for treatment benefit in multivariate analyses. Patients with baseline NLR<5 had a significantly improved PFS (HR=0.38; 95% CI: 0.22-0.66; P=0.0006) and OS (HR=0.24; 95% CI: 0.13-0.46; P<0.0001) compared with those with a NLR⩾5. Associations of low NLR with improved survival were confirmed in three validation cohorts of patients. CONCLUSION: Our findings show that baseline NLR is strongly and independently associated with outcome of patients treated with ipilimumab, and may serve to identify patients most likely to benefit from this therapy.

Three-year follow-up of advanced melanoma patients who received ipilimumab plus fotemustine in the Italian Network for Tumor Biotherapy (NIBIT)-M1 phase II study.

BACKGROUND: In the NIBIT-M1 study, we reported a promising activity of ipilimumab combined with fotemustine in metastatic melanoma (MM) patients with or without brain metastases. To corroborate these initial findings, we now investigated the long-term efficacy of this combination. PATIENTS AND METHODS: This analysis captured the 3-year outcome of MM patients who received ipilimumab combined with fotemustine as first- or second-line treatment. Median overall survival (OS), 3-year survival rates, immune-related (ir) progression-free survival (irPFS), brain PFS, and ir duration of response (irDOR) for the entire population and for patients with brain metastases were assessed. Clinical results were correlated with circulating CD3(+)CD4(+)ICOS(+)CD45RO(+) or CD45RA(+) T cells, neutrophil/lymphocyte (N/L) ratios, and tumorBRAF-V600 mutational status. RESULTS: Eighty-six MM patients, including 20 with asymptomatic brain metastases that had been pre-treated with radiotherapy in 7 subjects, were enrolled in the study. With a median follow-up of 39.9 months, median OS and 3-year survival rates were 12.9 months [95% confidence interval (CI) 7.1-18.7 months] and 28.5% for the whole study population, and 12.7 months (95% CI 2.7-22.7 months) and 27.8% for patients with brain metastases, respectively. Long-term ir adverse events consisting of G1 rush and pruritus occurred in 21% of patients. The absolute increase from baseline to week 12 in 'memory' but not in 'naïve' T cells identified patients with a better survival (P = 0.002). The N/L ratio correlated with a significantly better survival at early time points. BRAF status did not correlate with clinical outcome. CONCLUSIONS: Long-term analysis of the NIBIT-M1 trial continues to demonstrate efficacy of ipilimumab combined with fotemustine in MM patients. Fotemustine does not seem to impair the immunologic activity of ipilimumab. EUDRACT NUMBER: 2010-019356-50. CINICALTRIALSGOV: NCT01654692.

Primary hepatic epithelioid hemangioendothelioma progressively responsive to interferon-alpha: is there room for novel anti-angiogenetic treatments?

Primary hepatic epithelioid hemangioendothelioma (HEH) is a rare, low-grade malignant neoplasm of endothelial origin, with an unpredictable clinical course and prognosis. No standard therapeutic strategies are still available for HEH, due to the infrequency of the disease and to its variable natural history that limit the identification of the most effective treatment. In the absence of metastatic disease, surgical resection or liver transplantation represent the treatment of choice for HEH, while several antineoplastic agents have been proposed in the presence of metastatic nonresectable disesase. Herein, we describe the biological characterization and the clinical course of a primary HEH progressively responsive to treatment with intermediate doses of interferon-alpha (IFN)-alpha2a. Furthermore, based on the newly-identified expression of endoglin (CD105) on HEH, we discuss the clinical potential of novel anti-angiogenetic approaches to the disease.