Durable local control with hypofractionated radiation therapy for unresectable or metastatic melanoma.

Background and purpose: As patients with advanced melanoma live longer in the context of systemic therapy advancements, better strategies for durable control of bulky tumors are needed. In this study, we evaluated if dose-escalated hypofractionated radiation therapy (HFRT) can provide durable local control and improve tumor-associated symptoms in patients with unresectable or bulky metastatic melanoma for whom stereotactic ablative radiotherapy (RT) approaches are not feasible due to tumor size or location. Materials and methods: We retrospectively reviewed 49 patients with unresectable or bulky metastatic melanoma who were treated to a total of 53 tumor targets with 12-17 fractions HFRT at our institution between 2015-2022. Clinical scenarios included: unresectable, locoregional only disease (26 %); oligometastatic disease (<3 total sites, 17 %); oligoprogressive disease (<3 sites progressing, 17 %); and aggressive palliation (>5 known sites of disease or with at least 3 sites progressing, 40 %). Results: Of the 53 HFRT targets, 91 % (n = 48) had radiographic evidence of response as defined by either stabilization (6 %, n = 3), decreased size (74 %, n = 39), or decreased FDG avidity (11 %, n = 6). Of the 43 symptomatic patients, 98 % (n = 42) had symptomatic improvement. One -year local control was 79 %, with 2-year progression-free and overall survival of 33 % and 39 % respectively. The most common acute toxicities were radiation dermatitis (16 %, n = 8) or a pain flare (14 %, n = 7). Late toxicities were uncommon and typically grade 1. Conclusion: HFRT provides favorable local control and symptomatic relief with limited toxicity in tumors not amenable to surgical resection or stereotactic ablative RT.

Successful management of pre-existing psoriatic arthritis through targeting the IL-23/IL-17 axis in cancer patients receiving immune checkpoint inhibitor therapy: a case series.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have significantly improved outcomes for patients with cancer. However, these therapies are associated with adverse events including de novo immune-related adverse events or flare of pre-exiting autoimmune disorders. Up to 80% of patients with cancer and pre-existing psoriasis (PsO) or psoriatic arthritis (PsA) experience PsO/PsA flare after initiating ICIs. Targeting the interleukin (IL)-17/IL-23 axis is a mainstream of the PsO/PsA treatment. However, whether this treatment can effectively control PsO/PsA with ICI exposure while preserving anti-tumour efficacy remains unknown. CASE REPORTS: We report three patients with PsA and cancer, who received ICIs for their cancer treatment. All patients were male. Two patients had clear cell renal cell carcinoma, and one had melanoma. Two patients received anti-PD-1 antibody monotherapy, while one patient received combined anti-CTLA-4 and PD-1 antibody therapy. One patient had been receiving anti-IL-17A antibody (secukinumab), while the other two patients started anti-IL-17A antibody (ixekizumab) and anti-IL-23 antibody (guselkumab) after their PsA flared up during ICI treatment. Of note, with the anti-IL-17A or anti-IL-23 antibody treatment, their PsA remained in remission, and they well tolerated the ICI therapy. Importantly, all three patients showed persistent tumour responses to ICI therapy, including two complete remissions and one stable disease, respectively. CONCLUSIONS: These three cases suggest that targeting the IL-17/23 axis may be an effective and safe approach for patients with cancer and pre-existing PsA being considered for ICI therapy.

Survival and treatment outcomes in patients with leptomeningeal disease from metastatic melanoma.

Background: Melanoma leptomeningeal disease (LMD) has a poor prognosis. However, the management of patients with advanced melanoma has evolved with time, including those with LMD. We reviewed a large cohort of melanoma LMD patients to assess factors associated with survival. Methods: Retrospective clinical data was collected on patients diagnosed with LMD at MD Anderson Cancer Center from 2015 to 2020. Overall survival (OS) was determined from LMD diagnosis to date of death or last follow-up. The Kaplan-Meier method and log-rank test were used to estimate OS and to assess univariate group differences, respectively. Multivariable associations of survival with variables of interest were determined using Cox proportional hazards regression models. Results: A total of 172 patients were identified. The median age at LMD diagnosis was 53 (range 20-79) years, and all patients had radiographic evidence of LMD on magnetic resonance imaging of either brain or spine. In total 143 patients previously received systemic therapy (83%), with a median of 2 prior treatments (range 0-5). 81 patients (47%) had concurrent uncontrolled systemic disease and 80 patients (53%) had elevated serum LDH at the time of diagnosis. With a median follow-up of 4.0 months (range 0.1-65.3 months), median OS for all patients from LMD diagnosis was 4.9 months. Patients (n = 45) who received intrathecal therapy or systemic immunotherapy for LMD had a median OS of 8.0 months and 10.2 months, respectively. On multivariable analysis, decreased performance status, positive CSF cytology, elevated LDH, and whole brain radiation were associated with worse OS. Conclusions: Despite many advances in therapeutic options, the outcomes of melanoma patients with LMD remains poor. However, a subset of patients appears to derive benefit from LMD-directed treatment.

Baseline biomarkers of efficacy and on-treatment immune-profile changes associated with bempegaldesleukin plus nivolumab.

In PIVOT IO 001 (NCT03635983), the combination of the investigational interleukin-2 agonist bempegaldesleukin (BEMPEG) with nivolumab (NIVO) had no added clinical benefit over NIVO monotherapy in unresectable/metastatic melanoma. Pre-defined baseline and on-treatment changes in selected biomarkers were analyzed to explore the potential mechanisms underlying the clinical observations. In each treatment arm, higher baseline tumor mutational burden or immune infiltration/inflammation was associated with improved efficacy compared with lower levels. On-treatment peripheral biomarker changes showed that BEMPEG + NIVO increased all immune cell subset counts interrogated, including regulatory T cells. This was followed by attenuation of the increase in CD8 + T cells, conventional CD4 + T cells, and systemic interferon gamma levels at later treatment cycles in the combination arm. Changes in tumor biomarkers were comparable between arms. These biomarker results help provide a better understanding of the mechanism of action of BEMPEG + NIVO and may help contextualize the clinical observations from PIVOT IO 001.

Safety and effectiveness of combination versus monotherapy with immune checkpoint inhibitors in patients with preexisting autoimmune diseases.

Patients with preexisting autoimmune disease (pAID) are generally excluded from clinical trials for immune checkpoint inhibitors (ICIs) for cancer due to concern of flaring pAID. In this multi-center, retrospective observational study, we compared safety of ICI combination (two ICI agents) versus monotherapy in cancer patients with pAIDs. The primary outcome was time to AEs (immune-related adverse events (irAEs) and/or pAID flares), with progression-free survival (PFS) and overall survival as secondary outcomes. Sixty-four of 133 patients (48%) received ICI combination and 69 (52%) monotherapy. Most had melanoma (32%) and lung cancer (31%). Most common pAIDs were rheumatic (28%) and dermatologic (23%). Over a median follow-up of 15 months (95%CI, 11-18 mo), the cumulative incidence of any-grade irAEs was higher for combination compared to monotherapy (subdistribution hazard ratio (sHR) 2.27, 95%CI 1.35-3.82). No statistically significant difference was observed in high-grade irAEs (sHR 2.31 (0.95-5.66), P = .054) or the cumulative incidence of pAID flares. There was no statistically significant difference for melanoma PFS between combination versus monotherapy (23.2 vs. 17.1mo, P = .53). The combination group was more likely to discontinue or hold ICI, but > 50% of the combination group was still able to continue ICI therapy. No treatment-related deaths occurred. In our cohort with pAIDs, patients had a tolerable toxicity profile with ICI combination therapy. Our results support the use of ICI combination if deemed necessary for cancer therapy in patients with pAIDs, since the ICI toxicities were comparable to monotherapy, able to be effectively managed and mostly did not require ICI interruption.

Infliximab for Treatment of Immune Adverse Events and Its Impact on Tumor Response.

Background: Immune-related adverse events (irAEs) challenge the use of immune checkpoint inhibitors (ICIs). We performed a retrospective study to evaluate response to infliximab for immune-related adverse event management, and infliximab's effect on progression-free survival (PFS) and overall survival (OS) with a focus on melanoma and genitourinary cancers. Methods: We retrospectively reviewed records of all cancer patients exposed to infliximab after immune checkpoint inhibitor (ICI) treatment from 2004 to 2021 at the MD Anderson Cancer Center. Survival was assessed utilizing the Kaplan-Meier method. Univariate and multivariate logistic regression was utilized to evaluate predictors of infliximab response, OS, and PFS. Results: We identified 185 cancer patients (93 melanoma and 37 genitourinary cancers) treated with ICI and who received infliximab to treat irAEs. Within 3 months of treatment initiation, 71% of the patients responded to infliximab, 27% had no response, and 2% had unknown response. Among different irAEs, colitis was associated with increased response to infliximab at 3 months, irrespective of the type of malignancy. We evaluated best tumor response before and after infliximab in the entire cohort and again in the melanoma and genitourinary (GU); the findings were similar in the melanoma cohort and the entire cohort, where best tumor response before and after infliximab was not significantly different. In the melanoma cohort, acute kidney injury (AKI) was associated with increased risk of death, p = 0.0109, and having response to infliximab was associated with decreased risk of death, p = 0.0383. Interestingly in GU cancer patients, myositis was associated with increased risk of death, p = 0.0041, and having a response to infliximab was marginally associated with decreased risk of death, p = 0.0992. As regards PFS, in a multivariate Cox regression model, having a history of cardiovascular disease remained significantly associated with shorter PFS in the melanoma cohort. For patients with GU cancers, response to infliximab was associated with longer PFS. Conclusions: Our study is among the largest retrospective analyses of infliximab use for irAE management. Patients with colitis were the best responders to infliximab. AKI before initiation of infliximab in the melanoma subcohort and myositis in GU subcohort are associated with higher risk of death. Our results indicate no association between infliximab and cancer progression with the exception of genitourinary cancers.

Bempegaldesleukin Plus Nivolumab in Untreated Advanced Melanoma: The Open-Label, Phase III PIVOT IO 001 Trial Results.

PURPOSE: Despite marked advances in the treatment of unresectable or metastatic melanoma, the need for novel therapies remains. Bempegaldesleukin (BEMPEG), a pegylated interleukin-2 (IL-2) cytokine prodrug, demonstrated efficacy in the phase II PIVOT-02 trial. PIVOT IO 001 (ClinicalTrials.gov identifier: NCT03635983) is a phase III, randomized, open-label study that builds on the PIVOT-02 results in first-line melanoma. METHODS: Patients with previously untreated, unresectable, or metastatic melanoma were randomly assigned 1:1 to receive BEMPEG plus nivolumab (NIVO) or NIVO monotherapy. Primary end points were objective response rate (ORR) and progression-free survival (PFS) by blinded independent central review and overall survival (OS). Secondary and exploratory end points included additional efficacy measures, safety, and pharmacokinetics (PKs) and pharmacodynamics analyses. RESULTS: In 783 patients (n = 391, BEMPEG plus NIVO; n = 392, NIVO monotherapy), the median follow-up was 11.6 months in the intent-to-treat population. The ORR with BEMPEG plus NIVO was 27.7% versus 36.0% with NIVO (two-sided P = .0311). The median PFS with BEMPEG plus NIVO was 4.17 months (95% CI, 3.52 to 5.55) versus 4.99 months (95% CI, 4.14 to 7.82) with NIVO (hazard ratio [HR], 1.09; 97% CI, 0.88 to 1.35; P = .3988). The median OS was 29.67 months (95% CI, 22.14 to not reached [NR]) with BEMPEG plus NIVO versus 28.88 months (95% CI, 21.32 to NR) with NIVO (HR, 0.94; 99.929% CI, 0.59 to 1.48; P = .6361). Grade 3-4 treatment-related adverse events (AEs) and serious AE rates were higher with the combination (21.7% and 10.1%, respectively) versus NIVO (11.5% and 5.5%, respectively). BEMPEG PK exposure and absolute lymphocyte count changes after BEMPEG plus NIVO were comparable between PIVOT IO 001 and PIVOT-02. CONCLUSION: The PIVOT IO 001 study did not meet its primary end points of ORR, PFS, and OS. Increased toxicity was observed with BEMPEG plus NIVO versus NIVO.

Selective immune suppression using interleukin-6 receptor inhibitors for management of immune-related adverse events.

BACKGROUND: Management of immune-related adverse events (irAEs) is important as they cause treatment interruption or discontinuation, more often seen with combination immune checkpoint inhibitor (ICI) therapy. Here, we retrospectively evaluated the safety and effectiveness of anti-interleukin-6 receptor (anti-IL-6R) as therapy for irAEs. METHODS: We performed a retrospective multicenter study evaluating patients diagnosed with de novo irAEs or flare of pre-existing autoimmune disease following ICI and were treated with anti-IL-6R. Our objectives were to assess the improvement of irAEs as well as the overall tumor response rate (ORR) before and after anti-IL-6R treatment. RESULTS: We identified a total of 92 patients who received therapeutic anti-IL-6R antibodies (tocilizumab or sarilumab). Median age was 61 years, 63% were men, 69% received anti-programmed cell death protein-1 (PD-1) antibodies alone, and 26% patients were treated with the combination of anti-cytotoxic T lymphocyte antigen-4 and anti-PD-1 antibodies. Cancer types were primarily melanoma (46%), genitourinary cancer (35%), and lung cancer (8%). Indications for using anti-IL-6R antibodies included inflammatory arthritis (73%), hepatitis/cholangitis (7%), myositis/myocarditis/myasthenia gravis (5%), polymyalgia rheumatica (4%), and one patient each with autoimmune scleroderma, nephritis, colitis, pneumonitis and central nervous system vasculitis. Notably, 88% of patients had received corticosteroids, and 36% received other disease-modifying antirheumatic drugs (DMARDs) as first-line therapies, but without adequate improvement. After initiation of anti-IL-6R (as first-line or post-corticosteroids and DMARDs), 73% of patients showed resolution or change to ≤grade 1 of irAEs after a median of 2.0 months from initiation of anti-IL-6R therapy. Six patients (7%) stopped anti-IL-6R due to adverse events. Of 70 evaluable patients by RECIST (Response Evaluation Criteria in Solid Tumors) V.1.1 criteria; the ORR was 66% prior versus 66% after anti-IL-6R (95% CI, 54% to 77%), with 8% higher complete response rate. Of 34 evaluable patients with melanoma, the ORR was 56% prior and increased to 68% after anti-IL-6R (p=0.04). CONCLUSION: Targeting IL-6R could be an effective approach to treat several irAE types without hindering antitumor immunity. This study supports ongoing clinical trials evaluating the safety and efficacy of tocilizumab (anti-IL-6R antibody) in combination with ICIs (NCT04940299, NCT03999749).

Physician Views on the Provision of Information on Immune Checkpoint Inhibitor Therapy to Patients with Cancer and Pre-Existing Autoimmune Disease: A Qualitative Study.

Immune checkpoint inhibitors (ICIs) have improved cancer outcomes but can cause severe immune-related adverse events (irAEs) and flares of autoimmune conditions in cancer patients with pre-existing autoimmune disease. The objective of this study was to identify the information physicians perceived as most useful for these patients when discussing treatment initiation with ICIs. Twenty physicians at a cancer institution with experience in the treatment of irAEs were interviewed. Qualitative thematic analysis was performed to organize and interpret data. The physicians were 11 medical oncologists and 9 non-oncology specialists. The following themes were identified: (1) current methods used by physicians to provide information to patients and delivery options; (2) factors to make decisions about whether or not to start ICIs in patients who have cancer and pre-existing autoimmune conditions; (3) learning points for patients to understand; (4) preferences for the delivery of ICI information; and (5) barriers to the implementation of ICI information in clinics. Regarding points to discuss with patients, physicians agreed that the benefits of ICIs, the probability of irAEs, and risks of underlying autoimmune condition flares with the use of ICIs were most important. Non-oncologists were additionally concerned about how ICIs affect the autoimmune disease (e.g., impact on disease activity, need for changes in medications for the autoimmune disease, and monitoring of autoimmune conditions).

Safety and Activity of Immune Checkpoint Inhibitors in People Living With HIV and Cancer: A Real-World Report From the Cancer Therapy Using Checkpoint Inhibitors in People Living With HIV-International (CATCH-IT) Consortium.

PURPOSE: Compared with people living without HIV (PWOH), people living with HIV (PWH) and cancer have traditionally been excluded from immune checkpoint inhibitor (ICI) trials. Furthermore, there is a paucity of real-world data on the use of ICIs in PWH and cancer. METHODS: This retrospective study included PWH treated with anti-PD-1- or anti-PD-L1-based therapies for advanced cancers. Kaplan-Meier method was used to estimate overall survival (OS) and progression-free survival (PFS). Objective response rates (ORRs) were measured per RECIST 1.1 or other tumor-specific criteria, whenever feasible. Restricted mean survival time (RMST) was used to compare OS and PFS between matched PWH and PWOH with metastatic NSCLC (mNSCLC). RESULTS: Among 390 PWH, median age was 58 years, 85% (n = 331) were males, 36% (n = 138) were Black; 70% (n = 274) received anti-PD-1/anti-PD-L1 monotherapy. Most common cancers were NSCLC (28%, n = 111), hepatocellular carcinoma ([HCC]; 11%, n = 44), and head and neck squamous cell carcinoma (HNSCC; 10%, n = 39). Seventy percent (152/216) had CD4+ T cell counts ≥200 cells/µL, and 94% (179/190) had HIV viral load <400 copies/mL. Twenty percent (79/390) had any grade immune-related adverse events (irAEs) and 7.7% (30/390) had grade ≥3 irAEs. ORRs were 69% (nonmelanoma skin cancer), 31% (NSCLC), 16% (HCC), and 11% (HNSCC). In the matched mNSCLC cohort (61 PWH v 110 PWOH), 20% (12/61) PWH and 22% (24/110) PWOH had irAEs. Adjusted 42-month RMST difference was -0.06 months (95% CI, -5.49 to 5.37; P = .98) for PFS and 2.23 months (95% CI, -4.02 to 8.48; P = .48) for OS. CONCLUSION: Among PWH, ICIs demonstrated differential activity across cancer types with no excess toxicity. Safety and activity of ICIs were similar between matched cohorts of PWH and PWOH with mNSCLC.

Comparative safety and effectiveness of TNF inhibitors, IL6 inhibitors and methotrexate for the treatment of immune checkpoint inhibitor-associated arthritis.

OBJECTIVES: To compare the safety and effectiveness of biologic and conventional disease-modifying antirheumatic drugs (DMARDs) for immune checkpoint inhibitor-associated inflammatory arthritis (ICI-IA). METHODS: The retrospective multicentre observational study included patients with a diagnosis of ICI-IA treated with a tumour necrosis factor inhibitor (TNFi), interleukin-6 receptor inhibitor (IL6Ri) and/or methotrexate (MTX); patients with pre-existing autoimmune disease were excluded. The primary outcome was time to cancer progression from ICI initiation; the secondary outcome was time to arthritis control from DMARD initiation. Cox proportional hazard models were used to compare medication groups, adjusting for confounders. RESULTS: 147 patients were included (mean age 60.3 (SD 11.9) years, 66 (45%) women). ICI-IA treatment was TNFi in 33 (22%), IL6Ri 42 (29%) and MTX 72 (49%). After adjustment for time from ICI initiation to DMARD initiation, time to cancer progression was significantly shorter for TNFi compared with MTX (HR 3.27 (95% CI 1.21 to 8.84, p=0.019)) while the result for IL6Ri was HR 2.37 (95% CI 0.94 to 5.98, p=0.055). Time to arthritis control was faster for TNFi compared with MTX (HR 1.91 (95% CI 1.06 to 3.45, p=0.032)) while the result for IL6Ri was HR 1.66 (95% CI 0.93 to 2.97, p=0.089). A subset analysis in patients with melanoma gave similar results for both cancer progression and arthritis control. CONCLUSION: The treatment of ICI-IA with a biologic DMARD is associated with more rapid arthritis control than with MTX, but may be associated with a shorter time to cancer progression.

Concurrent intrathecal and intravenous nivolumab in leptomeningeal disease: phase 1 trial interim results.

There is a critical need for effective treatments for leptomeningeal disease (LMD). Here, we report the interim analysis results of an ongoing single-arm, first-in-human phase 1/1b study of concurrent intrathecal (IT) and intravenous (IV) nivolumab in patients with melanoma and LMD. The primary endpoints are determination of safety and the recommended IT nivolumab dose. The secondary endpoint is overall survival (OS). Patients are treated with IT nivolumab alone in cycle 1 and IV nivolumab is included in subsequent cycles. We treated 25 patients with metastatic melanoma using 5, 10, 20 and 50 mg of IT nivolumab. There were no dose-limiting toxicities at any dose level. The recommended IT dose of nivolumab is 50 mg (with IV nivolumab 240 mg) every 2 weeks. Median OS was 4.9 months, with 44% and 26% OS rates at 26 and 52 weeks, respectively. These initial results suggest that concurrent IT and IV nivolumab is safe and feasible with potential efficacy in patients with melanoma LMD, including in patients who had previously received anti-PD1 therapy. Accrual to the study continues, including in patients with lung cancer. ClinicalTrials.gov registration: NCT03025256 .

Imaging features of immune checkpoint inhibitor-related nephritis with clinical correlation: a retrospective series of biopsy-proven cases.

OBJECTIVES: Imaging appearances of immune checkpoint inhibitor-related nephritis have not yet been described. The primary objective of this study is to describe the appearances of immunotherapy-related nephritis on computerized tomography (CT) and positron emission tomography (PET). The secondary objectives are to investigate the association of radiologic features with clinical outcomes. METHODS: CT and PET-CT scans before the initiation of immunotherapy (baseline), at nephritis, and after resolution of pathology-proven nephritis cases were reviewed. Total kidney volume, renal parenchymal SUVmax, renal pelvis SUVmax, and blood pool SUVmean were obtained. RESULTS: Thirty-four patients were included. The total kidney volume was significantly higher at nephritis compared to baseline (464.7 ± 96.8 mL vs. 371.7 ± 187.7 mL; p < 0.001). Fifteen patients (44.1%) had > 30% increase in total kidney volume, which was associated with significantly higher renal toxicity grade (p = 0.007), higher peak creatinine level (p = 0.004), and more aggressive medical treatment (p = 0.011). New/increasing perinephric fat stranding was noted in 10 patients (29.4%) at nephritis. Among 8 patients with contrast-enhanced CT at nephritis, one (12.5%) developed bilateral wedge-shaped hypoenhancing cortical. On PET-CT, the renal parenchymal SUVmax-to-blood pool ratio was significantly higher at nephritis compared to baseline (2.13 vs. 1.68; p = 0.035). The renal pelvis SUVmax-to-blood pool SUVmean ratio was significantly lower at nephritis compared to baseline (3.47 vs. 8.22; p = 0.011). CONCLUSIONS: Bilateral increase in kidney size, new/increasing perinephric stranding, and bilateral wedge-shaped hypoenhancing cortical foci can occur in immunotherapy-related nephritis. On PET-CT, a diffuse increase in radiotracer uptake throughout the renal cortex and a decrease in radiotracer activity in the renal pelvis can be seen. KEY POINTS: • CT features of immune checkpoint inhibitor-related nephritis include an increase in kidney volume, new/increasing perinephric stranding, and bilateral ill-defined wedge-shaped hypoenhancing cortical foci. • FDG-PET features of immune checkpoint inhibitor-related nephritis include an increase in FDG uptake throughout the renal cortex and a decrease in FDG activity/excretion in the collecting system. • > 30% increase in total kidney volume is associated with worse toxicity grade and more aggressive medical management.

Intestinal toxicity to CTLA-4 blockade driven by IL-6 and myeloid infiltration.

Immune checkpoint blockade (ICB) has revolutionized cancer treatment, yet quality of life and continuation of therapy can be constrained by immune-related adverse events (irAEs). Limited understanding of irAE mechanisms hampers development of approaches to mitigate their damage. To address this, we examined whether mice gained sensitivity to anti-CTLA-4 (αCTLA-4)-mediated toxicity upon disruption of gut homeostatic immunity. We found αCTLA-4 drove increased inflammation and colonic tissue damage in mice with genetic predisposition to intestinal inflammation, acute gastrointestinal infection, transplantation with a dysbiotic fecal microbiome, or dextran sodium sulfate administration. We identified an immune signature of αCTLA-4-mediated irAEs, including colonic neutrophil accumulation and systemic interleukin-6 (IL-6) release. IL-6 blockade combined with antibiotic treatment reduced intestinal damage and improved αCTLA-4 therapeutic efficacy in inflammation-prone mice. Intestinal immune signatures were validated in biopsies from patients with ICB colitis. Our work provides new preclinical models of αCTLA-4 intestinal irAEs, mechanistic insights into irAE development, and potential approaches to enhance ICB efficacy while mitigating irAEs.

Neoadjuvant checkpoint inhibitor immunotherapy for resectable mucosal melanoma.

Background: Neoadjuvant checkpoint inhibition (CPI) has recently demonstrated impressive outcomes in patients with stage 3 cutaneous melanoma. However, the safety, efficacy, and outcome of neoadjuvant CPI in patients with mucosal melanoma (MM) are not well studied as MM is a rare melanoma subtype. CPI such as combination nivolumab and ipilimumab achieves response rates of 37-43% in unresectable or metastatic MM but there is limited data regarding the efficacy of these agents in the preoperative setting. We hypothesize that neoadjuvant CPI is a safe and feasible approach for patients with resectable MM. Method: Under an institutionally approved protocol, we identified adult MM patients with resectable disease who received neoadjuvant anti-PD1 +/- anti-CTLA4 between 2015 to 2019 at our institution. Clinical information include age, gender, presence of nodal involvement or satellitosis, functional status, pre-treatment LDH, tumor mutation status, and treatment data was collected. Outcomes include event free survival (EFS), overall survival (OS), objective response rate (ORR), pathologic response rate (PRR), and grade ≥3 toxicities. Results: We identified 36 patients. Median age was 62; 58% were female. Seventy-eight percent of patients received anti-PD1 + anti-CTLA4. Node positive disease or satellite lesions was present at the time of treatment initiation in 47% of patients. Primary sites of disease were anorectal (53%), urogenital (25%), head and neck (17%), and esophageal (6%). A minority of patients did not undergo surgery due to complete response (n=3, 8%) and disease progression (n=6, 17%), respectively. With a median follow up of 37.9 months, the median EFS was 9.2 months with 3-year EFS rate of 29%. Median OS had not been reached and 3-year OS rate was 55%. ORR was 47% and PRR was 35%. EFS was significantly higher for patients with objective response and for patients with pathologic response. OS was significantly higher for patients with pathologic response. Grade 3 toxicities were reported in 39% of patients. Conclusion: Neoadjuvant CPI for resectable MM is a feasible approach with signs of efficacy and an acceptable safety profile. As there is currently no standard approach for resectable MM, this study supports further investigations using neoadjuvant therapy for these patients.

Neoadjuvant relatlimab and nivolumab in resectable melanoma.

Relatlimab and nivolumab combination immunotherapy improves progression-free survival over nivolumab monotherapy in patients with unresectable advanced melanoma1. We investigated this regimen in patients with resectable clinical stage III or oligometastatic stage IV melanoma (NCT02519322). Patients received two neoadjuvant doses (nivolumab 480 mg and relatlimab 160 mg intravenously every 4 weeks) followed by surgery, and then ten doses of adjuvant combination therapy. The primary end point was pathologic complete response (pCR) rate2. The combination resulted in 57% pCR rate and 70% overall pathologic response rate among 30 patients treated. The radiographic response rate using Response Evaluation Criteria in Solid Tumors 1.1 was 57%. No grade 3-4 immune-related adverse events were observed in the neoadjuvant setting. The 1- and 2-year recurrence-free survival rate was 100% and 92% for patients with any pathologic response, compared to 88% and 55% for patients who did not have a pathologic response (P = 0.005). Increased immune cell infiltration at baseline, and decrease in M2 macrophages during treatment, were associated with pathologic response. Our results indicate that neoadjuvant relatlimab and nivolumab induces a high pCR rate. Safety during neoadjuvant therapy is favourable compared to other combination immunotherapy regimens. These data, in combination with the results of the RELATIVITY-047 trial1, provide further confirmation of the efficacy and safety of this new immunotherapy regimen.

First-in-human study of an OX40 (ivuxolimab) and 4-1BB (utomilumab) agonistic antibody combination in patients with advanced solid tumors.

BACKGROUND: Ivuxolimab (PF-04518600) and utomilumab (PF-05082566) are humanized agonistic IgG2 monoclonal antibodies against OX40 and 4-1BB, respectively. This first-in-human, multicenter, open-label, phase I, dose-escalation/dose-expansion study explored safety, tolerability, pharmacokinetics, pharmacodynamics, and antitumor activity of ivuxolimab+utomilumab in patients with advanced solid tumors. METHODS: Dose-escalation: patients with advanced bladder, gastric, or cervical cancer, melanoma, head and neck squamous cell carcinoma, or non-small cell lung cancer (NSCLC) who were unresponsive to available therapies, had no standard therapy available or declined standard therapy were enrolled into five dose cohorts: ivuxolimab (0.1-3 mg/kg every 2 weeks (Q2W)) intravenously plus utomilumab (20 or 100 mg every 4 weeks (Q4W)) intravenously. Dose-expansion: patients with melanoma (n=10) and NSCLC (n=20) who progressed on prior anti-programmed death receptor 1/programmed death ligand-1 and/or anti-cytotoxic T-lymphocyte-associated antigen 4 (melanoma) received ivuxolimab 30 mg Q2W intravenously plus utomilumab 20 mg Q4W intravenously. Adverse events (AEs) were graded per National Cancer Institute Common Terminology Criteria for Adverse Events V.4.03 and efficacy was assessed using Response Evaluation Criteria in Solid Tumors (RECIST) V.1.1 and immune-related RECIST (irRECIST). Paired tumor biopsies and whole blood were collected to assess pharmacodynamic effects and immunophenotyping. Whole blood samples were collected longitudinally for immunophenotyping. RESULTS: Dose-escalation: 57 patients were enrolled; 2 (3.5%) patients with melanoma (0.3 mg/kg+20 mg and 0.3 mg/kg+100 mg) achieved partial response (PR), 18 (31.6%) patients achieved stable disease (SD); the disease control rate (DCR) was 35.1% across all dose levels. Dose-expansion: 30 patients were enrolled; 1 patient with NSCLC achieved PR lasting >77 weeks. Seven of 10 patients with melanoma (70%) and 7 of 20 patients with NSCLC (35%) achieved SD: median (range) duration of SD was 18.9 (13.9-49.0) weeks for the melanoma cohort versus 24.1 (14.3-77.9+) weeks for the NSCLC cohort; DCR (NSCLC) was 40%. Grade 3-4 treatment-emergent AEs were reported in 28 (49.1%) patients versus 11 (36.7%) patients in dose-escalation and dose-expansion, respectively. There were no grade 5 AEs deemed attributable to treatment. Ivuxolimab area under the concentration-time curve increased in a dose-dependent manner at 0.3-3 mg/kg doses. CONCLUSIONS: Ivuxolimab+utomilumab was found to be well tolerated and demonstrated preliminary antitumor activity in selected groups of patients. TRIAL REGISTRATION NUMBER: NCT02315066.