Faculty Bibliography

Importance/UNASSIGNED:Use of prognostic gene expression profile (GEP) testing in cutaneous melanoma (CM) is rising despite a lack of endorsement as standard of care. Objective/UNASSIGNED:To develop guidelines within the national Melanoma Prevention Working Group (MPWG) on integration of GEP testing into the management of patients with CM, including (1) review of published data using GEP tests, (2) definition of acceptable performance criteria, (3) current recommendations for use of GEP testing in clinical practice, and (4) considerations for future studies. Evidence Review/UNASSIGNED:The MPWG members and other international melanoma specialists participated in 2 online surveys and then convened a summit meeting. Published data and meeting abstracts from 2015 to 2019 were reviewed. Findings/UNASSIGNED:The MPWG members are optimistic about the future use of prognostic GEP testing to improve risk stratification and enhance clinical decision-making but acknowledge that current utility is limited by test performance in patients with stage I disease. Published studies of GEP testing have not evaluated results in the context of all relevant clinicopathologic factors or as predictors of regional nodal metastasis to replace sentinel lymph node biopsy (SLNB). The performance of GEP tests has generally been reported for small groups of patients representing particular tumor stages or in aggregate form, such that stage-specific performance cannot be ascertained, and without survival outcomes compared with data from the American Joint Committee on Cancer 8th edition melanoma staging system international database. There are significant challenges to performing clinical trials incorporating GEP testing with SLNB and adjuvant therapy. The MPWG members favor conducting retrospective studies that evaluate multiple GEP testing platforms on fully annotated archived samples before embarking on costly prospective studies and recommend avoiding routine use of GEP testing to direct patient management until prospective studies support their clinical utility. Conclusions and Relevance/UNASSIGNED:More evidence is needed to support using GEP testing to inform recommendations regarding SLNB, intensity of follow-up or imaging surveillance, and postoperative adjuvant therapy. The MPWG recommends further research to assess the validity and clinical applicability of existing and emerging GEP tests. Decisions on performing GEP testing and patient management based on these results should only be made in the context of discussion of testing limitations with the patient or within a multidisciplinary group.

Macroautophagy (hereafter autophagy) degrades and recycles intracellular components to sustain metabolism and survival during starvation. Host autophagy promotes tumor growth by providing essential tumor nutrients. Autophagy also regulates immune cell homeostasis and function and suppresses inflammation. Although host autophagy does not promote a T-cell anti-tumor immune response in tumors with low tumor mutational burden (TMB), whether this was the case in tumors with high TMB was not known. Here we show that autophagy, especially in the liver, promotes tumor immune tolerance by enabling regulatory T-cell function and limiting stimulator of interferon genes, T-cell response and interferon-γ, which enables growth of high-TMB tumors. We have designated this as hepatic autophagy immune tolerance. Autophagy thereby promotes tumor growth through both metabolic and immune mechanisms depending on mutational load and autophagy inhibition is an effective means to promote an antitumor T-cell response in high-TMB tumors.

BACKGROUND:Despite a protracted disease course and multiple available therapies, patients with well-differentiated neuroendocrine tumors (NETs) inevitably experience disease progression. Programmed death-ligand 1 (PD-L1) has been associated with NET progression and prognosis. The multicohort, phase 1 KEYNOTE-028 study (ClinicalTrials.gov identifier NCT02054806) evaluated the activity and safety of the anti-programmed cell death protein 1 immunotherapy pembrolizumab in patients with well-differentiated or moderately-differentiated NETs. METHODS:Patients with PD-L1-positive, locally advanced or metastatic carcinoid or well-differentiated or moderately-differentiated pancreatic NETs (pNETs) were enrolled into separate cohorts and received pembrolizumab at a dose of 10 mg/kg every 2 weeks for up to 2 years. The objective response rate was the primary endpoint (as per Response Evaluation Criteria in Solid Tumors version 1.1, by investigator review). Safety was a secondary endpoint. RESULTS:Of 170 and 106 patients, respectively, who had evaluable samples among those screened for the carcinoid and pNET cohorts, 21% and 25%, respectively, had PD-L1-positive tumors; of these, 25 and 16 patients, respectively, were eligible and treated. The median follow-up was 20 months (range, 2-35 months) and 21 months (range, 5-32 months), respectively. The objective response rate was 12.0% (95% CI, 2.5%-31.2%) and 6.3% (95% CI, 0.2%-30.2%), respectively; 3 partial responses occurred among the carcinoid cohort and 1 among the pNET cohort. The median duration of response in the carcinoid cohort was 9.2 months (range, 6.9-11.1 months), and was not reached in the pNET cohort. No complete responses occurred. Treatment-related adverse events occurred in 68% and 69% of patients, respectively, most often diarrhea (7 patients in the carcinoid cohort and 4 patients in the pNET cohort) and fatigue (6 patients in each cohort). Hypothyroidism was the most common immune-mediated adverse event (5 patients in the carcinoid cohort and 2 patients in the pNET cohort). CONCLUSIONS:Pembrolizumab demonstrated antitumor activity in a subset of patients with NETs and was well-tolerated.

Intravesical BCG is a highly effective treatment for high-grade nonmuscle invasive bladder cancer and carcinoma in situ (CIS); however, for patients who are either resistant or become unresponsive to BCG therapy there is a need for alternative treatment approaches. This study examined the safety and feasibility of intravesically administered recombinant fowlpox virus encoding GM-CSF (Arm A) or TRICOM (Arm B); and the local and systemic immunologic responses generated to the vector(s). Twenty bladder cancer patients scheduled for cystectomy as their standard of care received preoperatively four weekly doses of intravesical recombinant fowlpox. Treatment was well tolerated, however, three patients experienced transient elevations of liver transaminases, with one rising to the level of a DLT. Cystectomy derived tumor and normal bladder mucosa demonstrated mRNA for the virally encoded LacZ gene supporting effective infection/transfection. Detected serum antibody to the LacZ encoding β-galactosidase indicated successful expression of vector-encoding gene products and the ability to immunize via the bladder site. H&E and IHC using a panel of immune cell specific antigens demonstrated immune cell infiltration of the bladder wall. These findings demonstrate good safety profile, successful infection/transfection, ability to generate systemic immune response, and local recruitment of immune cell populations with intravesical administration of fowlpox-based constructs encoding for GM-CSF(rF-GM-CSF) or TRICOM (rF-TRICOM), and support further evaluation of this treatment modality for bladder cancer.

Background AT-101 is a BH3 mimetic that inhibits the heterodimerization of Bcl-2, Bcl-xL, Bcl-W, and Mcl-1 with pro-apoptotic proteins, thereby lowering the threshold for apoptosis. This phase I trial investigated the MTD of AT-101 in combination with paclitaxel and carboplatin in patients with advanced solid tumors. Methods Patients were treated with AT-101 (40 mg) every 12 h on days 1, 2 and 3 of each cycle combined with varying dose levels (DL) of paclitaxel and carboplatin [DL1: paclitaxel (150 mg/m²) and carboplatin (AUC 5) on day 1 of each cycle; DL2: paclitaxel (175 mg/m²) and carboplatin (AUC 6) on day 1 of each cycle]. Secondary objectives included characterizing toxicity, efficacy, pharmacokinetics, and pharmacodynamics of the combination. Results Twenty-four patients were treated across two DLs with a planned expansion cohort. The most common tumor type was prostate (N = 11). Two patients experienced DLTs: grade 3 abdominal pain at DL1 and grade 3 ALT increase at DL2; however, the MTD was not determined. Moderate hematologic toxicity was observed. One CR was seen in a patient with esophageal cancer and 4 patients achieved PRs (1 NSCLC, 3 prostate). PD studies did not yield statistically significant decreases in Bcl-2 and caspase 3 protein levels, or increased apoptotic activity induced by AT-101. Conclusion The combination of AT-101 at 40 mg every 12 h on days 1, 2 and 3 combined with paclitaxel and carboplatin was safe and tolerable. Based on the modest clinical efficacy seen in this trial, this combination will not be further investigated. Clinical Trial Registration: NCT00891072, CTEP#: 8016.

BACKGROUND:Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer associated with a high risk of metastasis. In 2017, avelumab (anti-programmed death-ligand 1 (PD-L1)) became the first approved treatment for patients with metastatic MCC (mMCC), based on the occurrence of durable responses in a subset of patients. Here, we report long-term efficacy and safety data and exploratory biomarker analyses in patients with mMCC treated with avelumab. METHODS:In a cohort of this single-arm, phase 2 trial (JAVELIN Merkel 200), patients with mMCC and disease progression after prior chemotherapy received avelumab 10 mg/kg intravenously every 2 weeks. The primary endpoint was confirmed objective response rate (ORR) by independent review per Response Evaluation Criteria in Solid Tumors V.1.1. Other assessments included duration of response, progression-free survival, overall survival (OS), safety and biomarker analyses. RESULTS:As of 14 September 2018, 88 patients had been followed up for a median of 40.8 months (range 36.4-49.7 months). The ORR was 33.0% (95% CI 23.3% to 43.8%), including a complete response in 11.4% (10 patients), and the median duration of response was 40.5 months (95% CI 18.0 months to not estimable). As of 2 May 2019 (≥44 months of follow-up), the median OS was 12.6 months (95% CI 7.5 to 17.1 months) and the 42-month OS rate was 31% (95% CI 22% to 41%). Of long-term survivors (OS >36 months) evaluable for PD-L1 expression status (n=22), 81.8% had PD-L1+ tumors. In exploratory biomarker analyses, high tumor mutational burden (≥2 non-synonymous somatic variants per megabase) and high major histocompatibility complex class I expression (30% of tumors with highest expression) were associated with trends for improved ORR and OS. In long-term safety assessments (≥36 months of follow-up), no new or unexpected adverse events were reported, and no treatment-related deaths occurred. CONCLUSIONS:Avelumab showed continued durable responses and meaningful long-term survival outcomes in patients with mMCC, reinforcing avelumab as a standard-of-care treatment option for this disease. TRIAL REGISTRATION NUMBER/BACKGROUND:NCT02155647.

INTRODUCTION/BACKGROUND:Pembrolizumab has shown clinical benefit in patients with previously treated recurrent or metastatic SCLC in the phase 1b multicohort study KEYNOTE-028 (NCT02054806) and the phase 2 multicohort study KEYNOTE-158 (NCT02628067). We present a pooled analysis of patients from KEYNOTE-028 and KEYNOTE-158 who had received two or more lines of previous therapy for SCLC. METHODS:Eligible patients were aged 18 years and above, had histologically or cytologically confirmed incurable recurrent or metastatic SCLC, had an Eastern Cooperative Oncology Group performance status of 1 and below, and had received two or more lines of previous therapy. Patients in KEYNOTE-028 were required to have a programmed death ligand 1 (PD-L1)-positive tumor. Patients received pembrolizumab (10 mg/kg every 2 weeks in KEYNOTE-028 or 200 mg every 3 weeks in KEYNOTE-158) for up to 2 years. The primary end point was objective response rate per Response Evaluation Criteria in Solid Tumors version 1.1, which is presented here per independent review. RESULTS:Eighty-three patients who had received two or more lines of previous therapy (KEYNOTE-028, n = 19; KEYNOTE-158, n = 64) were included. Median follow-up duration was 7.7 (range, 0.5-48.7) months. Objective response rate was 19.3% (95% confidence interval: 11.4-29.4); two patients had complete response (one with a PD-L1-positive tumor), and 14 patients had partial response (13 with PD-L1-positive tumors). The median duration of response was not reached (range, 4.1‒35.8+ mo; plus sign indicates ongoing response); 61% of responders had responses lasting 18 months or longer. Fifty-one patients (61.4%) experienced any-grade treatment-related adverse events; eight patients (9.6%) had grade 3 or higher events. CONCLUSIONS:Pembrolizumab exhibited durable antitumor activity in a subset of patients with recurrent or metastatic SCLC who had undergone two or more previous lines of therapy, regardless of PD-L1 expression. Pembrolizumab was well tolerated.

PURPOSE:Given the evidence that coordinate inhibition of AKT induces autophagy, we studied the combination of the AKT inhibitor, MK-2206 with hydroxychloroquine (HCQ) in patients with advanced solid tumors. METHODS:Patients were treated with weekly MK-2206 (135 mg or 200 mg) plus HCQ (200 mg, 400 mg or 600 mg BID). RESULTS:Thirty-five patients were enrolled across 5 dose levels. Two DLTs of grade 3 maculo-papular rash were observed at dose level 2 (MK-2206 200 mg weekly plus HCQ at 400 mg BID) and 1 DLT of grade 3 fatigue at dose level 2B (MK-2206 135 mg weekly plus HCQ 600 mg BID). The maximum tolerated dose (MTD) was declared as dose level 2B. The most common adverse events attributed to MK-2206 were hyperglycemia (N = 18; 51%), fatigue (N = 17; 49%), maculo-papular rash (N = 16; 46%), diarrhea (N = 12; 34%), anorexia (N = 11; 31%), and nausea (N = 11; 31%). Patients experiencing adverse events attributed to HCQ were small in number (N = 13) and primarily included fatigue (N = 5; 14%) and maculo-papular rashes (N = 3; 9%). Statistically significant effects on the pharmacokinetic properties of MK-2206 were observed in combination with HCQ. In addition, the plasma concentrations of HCQ in the combination with MK-2206 were significantly higher than the plasma levels of HCQ as monotherapy in prior studies. The best overall response of stable disease was observed in 5/34 (15%) patients. CONCLUSION:The combination of MK-2206 and hydroxychloroquine was tolerable, but with substantial number of drug-related AEs and minimal evidence of antitumor activity.

BACKGROUND:Talimogene laherparepvec (T-VEC) is an intralesionally delivered, modified herpes simplex virus type-1 oncolytic immunotherapy. The biodistribution, shedding, and potential transmission of T-VEC was systematically evaluated during and after completion of therapy in adults with advanced melanoma. METHODS:PFU/mL every 14 (±3) days thereafter. Injected lesions were covered with occlusive dressings for ≥1 week. Blood, urine, and swabs from exterior of occlusive dressings, surface of injected lesions, oral mucosa, anogenital area, and suspected herpetic lesions were collected throughout the study. Detectable T-VEC DNA was determined for each sample type; infectivity was determined for all swabs with detectable T-VEC DNA. FINDINGS/RESULTS:Sixty patients received ≥1 dose of T-VEC. During cycles 1-4, T-VEC DNA was detected in blood (98·3% of patients, 36·7% of samples), urine (31·7% of patients, 3·0% of samples) and swabs from injected lesions (100% of patients, 57·6% of samples), exterior of dressings (80% of patients,19·5% of samples), oral mucosa (8·3% of patients, 2·5% of samples), and anogenital area (8·0% of patients, 1·1% of samples). During the safety follow-up period, T-VEC DNA was only detected on swabs from injected lesions (14% of patients, 5.8% of samples). T-VEC DNA was detected in 4/37 swabs (3/19 patients) of suspected herpetic lesions. Among all samples, only those from the surface of injected lesions tested positive for infectivity (8/740 [1·1%]). Three close contacts reported signs and symptoms of suspected herpetic origin; however, no lesions had detectable T-VEC DNA. INTERPRETATION/CONCLUSIONS:Using current guidelines, T-VEC can be administered safely to patients with advanced melanoma and is unlikely to be transmitted to close contacts with appropriate use of occlusive dressings. FUND: This study was funded by Amgen Inc.: ClinicalTrials.gov, NCT02014441.