Abstract 614: Resiquimod, a Toll-like receptor agonist promotes melanoma regression by enhancing plasmacytoid dendritic cells and T cytotoxic activity as a vaccination adjuvant and by direct tumor application

Introduction: Cancer immunotherapy is a modern strategy aiming at restoring the capacity of the immune system to target tumors in cancer patients. Toll-like receptor (TLR) agonists may enhance vaccination or direct immune activation at the tumor microenvironment. This clinical trial evaluated the biologic effects of Resiquimod, a TLR agonist that can activate both myeloid (TLR 8) and plasmacytoid (TLR 7) dendritic cells, on advanced stage melanoma. Methods: Subjects with in-transit melanoma metastases or high risk for recurrence and appropriate HLA were treated with peptide vaccination (class 1 restricted peptide GP100(g209-2m) and, if HLA-DP4+, class 2 restricted peptide MAGE-3243-258). Half of the patients were randomized to receive Resiquimod as an adjuvant applied to the GP100 vaccination site. Subjects with in-transit disease were then treated with resiquimod topically on half of the target lesions. To evaluate the T cell function, fresh PBMC and single cell tumor suspension were analyzed by flow cytometry using gp100-specific dextramer staining. RNA from the vaccination site was also analyzed using real-time PCR. Results: All patients (n=47) underwent GP100(g209-2m) vaccination, a majority (39) also received the MAGE-3243-258 peptide. Type 1 interferon pathway protein profiles of vaccination sites showed activation of plasmacytoid dendritic cells in patients with Resiquimod, but not in its absence. Nineteen subjects had in-transit disease at entry into the trial. In response to peptide vaccination alone, tumor regression was more likely in patients who received Resiquimod (group A) compared to those who did not (group B). (4/9 vs 0/10). In group A, 5 patients continued treatment with Resiquimod topically on the tumors, and all had tumor response (4PR, 1CR). In group B, 5 continued to tumoral resiquimod and 3 had regression (3 PR). Type I interferon (as measured by MxA and IRF7) IFN-gamma and TNF-alpha increased at the vaccination site 24 hrs after vaccination only at the sites where Resiquimod was applied. In blood, Resiquimod increased gp100-specific CD8 T cells frequency at week 8 (p=0.03) only in patients who received Resiquimod at the vaccination site. Conclusions: Resiquimod activates plasmacytoid dendritic cells at a peptide vaccination site and augments peptide vaccination sufficiently to mediate regression of in-transit melanoma metastasis. Resiquimod on in-transit melanoma, in vaccinated hosts, drives regression of metastases, regardless of previous exposure at vaccination site. An increased amount of cytokines such type I interferon, IFN-gamma, TNF-alpha, and T specific cytotoxic frequency were increased at the vaccination site after patients received Resiquimod.

Citation Format: Jorge A. Borin Scutti, Luis M. Vence, Richard E. Royal, Tara C. Wray, Janice N. Cormier, Jeffrey E. Lee, Anthony Lucci, Jeffrey E. Gershenwald, Merrick I. Ross, Jennifer Wargo, Karen A. Millerchip, Rodabe N. Amaria, Michael A. Davis, Adi Diab, Isabella C. Glitza, Wen Hwu, Sapna Patel, Scott E. Woodman, Willem W. Overwijk, Patrick Hwu. Resiquimod, a Toll-like receptor agonist promotes melanoma regression by enhancing plasmacytoid dendritic cells and T cytotoxic activity as a vaccination adjuvant and by direct tumor application [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 614.

Phase II study of vincristine sulfate liposomes injection in patients with metastatic uveal melanoma

9067

Background: Preclinical and clinical studies showed that liposomal encapsulation of vincristine sulfate (VCR) results in increased drug circulation time and accumulation of VCR at the tumor site. Marqibo has been administered safely at 2.25 mg/m2, a dose exceeding that typically employed for VCR ( dose capped at 2 mg), with tolerable clinical toxicities consistent with VCR. Of the 27 previously treated patients with metastatic melanoma in the Marqibo pharmacokinetic studies, 3 patients had a tumor response, including one patient with uveal melanoma metastatic to the lung that experienced a complete response. Methods: Patients with metastatic uveal melanoma with no more than one prior systemic therapy were enrolled. Patients with controlled brain metastases were allowed. Marqibo (2.25 mg/m2 by 1-hour intravenous infusion, no dose capping) was administered every 14 days until tumor progression. Responses were assessed every 6 weeks using the Response Evaluation Criteria in Solid Tumors (RECIST). Toxicity was assessed at least as frequently as before each dose. Results: Preliminary data is available for 22 enrolled patients (73% female). Median age was 65 years (range 38–79), 23% were previously treated with systemic chemotherapy, 86% had liver metastasis and 96% had M1c disease. Baseline serum LDH levels were elevated in 73% and were more than 2 × ULN in 37% of the patients. Twenty-one patients were evaluable for response; one patient discontinued the treatment after a single dose of therapy for toxicity without tumor progression. No patients died of drug toxicity while on the study. Twelve patients (57%) had stable disease. Estimated median survival is 6.4 months. Fourteen patients are alive, 2 for more than 12 months. Treatment related side effects were mostly grade 1 or 2; peripheral neuropathy was the only grade 3 toxicity, seen in 18% of the patients. The hematologic toxicities were minor; no neutropenia or thrombocytopenia was seen. Conclusions: Marqibo is well tolerated as single agent therapy in patients with advanced stage IV uveal melanoma. Its impact on the progression-free and overall survival of these critically ill patients will be presented.

No significant financial relationships to disclose.

Randomized trial of two schedules of palonosetron for the prevention of nausea and vomiting in patients with metastatic melanoma receiving interleukin-2–based concurrent biochemotherapy

e20008

Background: Interleukin-2–based biochemotherapy (BCT) is a common therapy for patients (pts) with metastatic melanoma (MM). BCT induced nausea and vomiting (N/V) remains a significant problem (26% grade 3 and 4). Palonosetron (PALO) is a 5-HT3 receptor antagonist indicated for the prevention of N/V associated with chemotherapy. The recommended dosing schedule of PALO for patients on BCT is unknown. Methods: Chemo-naïve MM pts undergoing their first BCT cycle were randomized to receive PALO 0.25 mg as premedication intravenously on days 1 and 4, or the same dose on days 1, 3, and 5. The BCT regimen included: cisplatin (20 mg/m2) and vinblastine (1.6 mg/m2) on days 1–4, dacarbazine (800 mg/m2) on day 1, interleukin-2 (9 MIU/m2/day) by continuous infusion on days 1–4 and interferon alpha (5 MU/m2/day) on days 1–5. A nausea episode was defined as nausea of any severity reported by the patient or documented by the nursing staff at anytime. Pts with N/V due to known central nervous system or gastrointestinal metastases were excluded. The use of additional antiemetics was recorded. Pts were followed for 21 days (days 1–7 as inpatients). The Functional Living Index-Emesis (FLIE), an emesis- and nausea-specific questionnaire, was completed starting on day 1. Results: 30 pts were enrolled. Median age was 53 years (range 23–64). Eighteen (60%) were men. The incidences of BCT related N/V and those of nausea interfering with appetite, sleep, physical activity, social life and enjoyment of life are summarized by schedule of PALO in the table below. Conclusions: PALO administered on alternate days was more effective at controlling BCT-related N/V and reduced the need for PRN antiemetics. Better control of N/V reduced the impact of N/V on patient functioning in this population.

[Table: see text]

No significant financial relationships to disclose.

Phase I/II study of the combination of sorafenib and temsirolimus in patients with metastatic melanoma

9026

Background: Inhibition of Signal transduction pathways at multiple levels may be a more effective therapeutic cancer strategy for advanced cancer patients. Sorafenib, a multikinase inhibitor and temsirolimus, an inhibitor of critical survival pathways, are targeted compounds with single agent anti-tumor activity in several solid tumors. Inhibition of mutant B-Raf and the AKT signaling pathway has been effective in vitro with melanoma cell lines. Therefore, we designed a phase I/II study of the combination of sorafenib and temsirolimus to inhibit multiple pathways for greater clinical efficacy.Methods: Patients (pts) with stage IV or unresectable or recurrent stage III melanoma and ECOG performance status of 0 to 1 were eligible. Pts with treated brain metastases were eligible if they had not progressed for 3 months. Sorafenib was given orally twice daily and temsirolimus was given intravenously once a week, both starting on day 1, with a 4-week cycle. Responses were assessed every 2 cycles per RECIST. Results: To date, 22 pts have been enrolled and treated. Median age was 56.5, and 17 were male. Median ECOG PS was 1. The MTD doses were sorafenib 400 mg in AM / 200 mg in PM daily and temsirolimus 25 mg IV weekly. The dose-limiting toxicity (DLT) included thrombocytopenia, hand-foot syndrome (HFS), serum transaminase elevation and hypertriglyceridemia. Other common adverse events were dry skin, fatigue, taste alteration, anorexia, flatulence, diarrhea, skin rash, insomnia, neuropathy, myalgia, and headaches, anemia, hypercholesterolemia, hyperglycemia and hypophosphatemia. There were 9 pts with stable disease among 21 evaluable pts for response. Conclusions: Sorafenib and temsirolimus can be administered concomitantly although with significant toxicity at higher dose levels. Currently, pts are enrolled in a dose expansion cohort. Pharmacokinetic data will be presented. Supported in part by NCI grant UO1 CA062461 and N01 CM17003.

[Table: see text]

No significant financial relationships to disclose.

Preliminary results from a phase I/II study of the combination of lenalidomide and DTIC in patients with metastatic malignant melanoma previously untreated with systemic chemotherapy

8533

Background: In metastatic melanoma (MM) no single agent has shown objective response greater than 21%, and none have made an impact on overall survival. DTIC is approved for MM with response rates of 7% to 21%. Lenalidomide, an immunomodulatory drug of the IMiDs class, was reported to enhance immune responses in MM patients. This study was designed to assess the safety and activity of lenalidomide in combination with DTIC in patients with metastatic melanoma (MM). Methods: Twenty-eight chemotherapy naive patients with unresectable stage III and IV MM enrolled in the study. All patients received 25 mg lenalidomide orally once daily on days 1–14 every 21 days and continued therapy as tolerated or until disease progression. DTIC was given IV over 1 hour on day 1 every 21 days. There were three dose levels for DTIC: 600 mg/m2, 800 mg/m2 and 1,000 mg/m2. Each dose level had 3–6 patients enrolled. Thirteen additional patients were to be enrolled at the MTD. Response and progression were evaluated using the RECIST criteria every 6 weeks. Results: As of December 21, 2006 twenty-six patients were evaluable for response. Median age was 65 (46–83) and 13 were female. Median ECOG was 1. Two patients (8%) exhibited an objective response (2 partial responses (PR)), 10 had stable disease (SD) for a tumor control rate (TCR) of 46 % and 14 progressive disease (PD). Thirteen patients have been enrolled at the MTD of 25 mg lenalidomide + 800 mg/m2 DTIC and most are still receiving therapy. Grade 3 or 4 adverse events occurred in 12 (43%) of the 28 patients receiving drug. Grade 3 events included: transient elevation of transaminases, increased temperature, headache, dizziness, low hemoglobin, and leg edema. Four patients (14%) experienced a Grade 4 adverse reaction (pulmonary emboli, low hemoglobin, cerebral hemorrhage, and cerebral ischemia). The most common Grade 1/2 adverse events included: fatigue, nausea, pruritis, muscle cramps, taste alteration, skin rash, and constipation. Conclusions: The MTD has been established at 25 mg lenalidomide + 800 mg/m2 DTIC. Preliminary results indicate that lenalidomide in combination with DTIC has manageable side effects in patients with MM. Evaluation of efficacy is ongoing.

No significant financial relationships to disclose.

Evaluation of tolerability, safety, and pharmacokinetics of INO-1001 plus temozolomide (TMZ) in patients with unresectable stage III/IV melanoma

12015

Background: TMZ, an orally bioavailable cytotoxic agent with the same active metabolite as DTIC, is a commonly used for treatment (Rx) of metastatic melanoma (MM). It causes methylation of the O6 position of guanine. Unrepaired O6-methylguanine pairs with thymine rather than guanine and activates DNA mismatch repair. Poly(ADP-ribose)polymerase-1 (PARP-1) is a nuclear protein that functions as DNA damage sensor. PARP inhibitors increase TMZ cytotoxicity by causing interruption of the repair process of N-methylpurines generated by TMZ. INO-1001 (INO), an ultrapotent PARP inhibitor has been tested in combination of TMZ and found to be safe and well tolerated. Here we report the initial results of Phase Ib clinical trial. Methods: Patients (pts) with unresectable stage III/IV MM with no prior Rx with TMZ or DTIC were treated with INO given IV q 12 hours for 10 doses at the starting dose of 100mg/dose. The doses of INO are planned to escalate from 100 to 200mg/dose and then to the maximum dose of 400 mg/dose in successive groups of 3–6 pts. TMZ is taken po within 2 hours of the second dose of INO at the dose of 200mg/m2/day for 5 days. Blood samples are collected for pharmacokinetics study during cycle 1. The Rx cycles are repeated q 4 weeks and tumor responses are evaluated q 8 weeks. Results: 6 pts with median age 63 (range 55–67) years and median PS Zubrod 1 (range 0–2) have been treated. Initially 3 pts were treated with INO at the dose level of 100mg. One pt with a BSA of 2.76 had grade 4 neutropenia and thrombocytopenia with Rx cycle 1. TMZ dose was not adjusted to her ideal body weight. Subsequently, the dose of TMZ was reduced by 25% and the following 2 cycles were tolerated well. 3 more pts were entered at the dose level 1. To date, a total of 8 cycles of Rx have been completed. All except for the cycle mentioned earlier were tolerated well. 3 pts were evaluated for response, 1 pt had objective tumor regression, 1 had stable disease and 1 had tumor progression. The non-hematologic side effects were mild and are mostly related to TMZ. Conclusions: TMZ-INO combination is fairly well tolerated. A complete report will be presented.

No significant financial relationships to disclose.

Natural history of metastatic melanoma patients with CNS metastases

8054

Background: Melanoma has a high rate of CNS metastasis (mets). The objective of this study was to evaluate the characteristics and outcomes of melanoma patients (pts) who develop CNS mets. Methods: 333 pts with a diagnosis of CNS mets were identified from databases of 743 chemotherapy naïve metastatic melanoma (MM) pts enrolled on clinical trials between 1986 and 2004. Their clinical and pathological characteristics were reviewed. Results: The site of primary melanoma was head or neck (60/333; 18%), trunk/abdomen (144/333; 43%), limbs (66/333; 20%), ocular (2/333; 1%), or unknown (61/333; 18%). Median Breslow thickness (BT) = 2.2 mm; BT < 1 mm = 39/217 (18%); and BT < 2 mm = 95/217 (44%). Median Clark level (CL)= IV; CL I = 0/180 (0%); CL II = 14/180 (8%); CL III = 70/180 (39%); and CL IV = 96/180 (53%) . The median interval from diagnosis of primary melanoma to CNS mets = 29.6 (range 0.3–393) months (mos). Median survival (MS) from CNS diagnosis = 4.6 (range 0–120) mos. MS was highest for pts with brain mets (n=307; 4.8 mos) compared to pts with brain mets plus leptomeningeal disease (LMD) (14; 2.0 mos) or pts with LMD alone (11; 1.2 mos) (p=.0048 for pts with LMD vs. without). MS varied for pts with 1 (6.6 mos), 2 (4.2 mos), 3 (5.9 mos) or >3 (3.5 mos) brain lesions at diagnosis of CNS mets. Among pts diagnosed with CNS mets at or prior to systemic therapy, MS was longer for pts with CNS mets only (n=20; 14.3 mos) compared to pts with CNS mets concurrent with extracranial mets (63; 7 mos) (p=.003). Patients who developed CNS mets after starting chemotherapy for extracranial mets (n=250; 3.7 mos) had a shorter MS than those diagnosed at or before systemic therapy (83; 7.9 mos, p<.001). Among pts diagnosed after starting systemic therapy, CNS mets were detected ≤ 12 months from the start of chemotherapy in 30% of pts (MS = 3 mos), 12–24 mos in 37% of pts (MS = 4.6 mos), and > 36 mos in 32% of pts (MS = 11.1 mos, p=.044 vs. other groups). Conclusions: This study represents one of the largest cohorts of pts with melanoma CNS mets. The presence of LMD, or development of CNS mets after starting systemic therapy, is associated with a worse prognosis. Among pts diagnosed with CNS mets at or before starting systemic therapy, the presence of concurrent non-CNS mets also portends for a worse outcome. Supported in part by Carol Courtney Memorial fund and Chiron Corporation.

No significant financial relationships to disclose.

Long-term clinical results of the combination of cisplatin (C), vinblastine (V), DTIC (D) and interferon-alfa (I) with or without tamoxifen (T) for metastatic melanoma

8039

Background: According to 2001 AJCC data, 1-yr, 2-yr, 5-yr, and 10-yr survival of melanoma patients (pts) with stage M1c were 40.6%, 23.6%, 9.5% and 6.0%, respectively. Previously, we reported the interim results of a randomized phase II trial comparing the response rates (RR) of CVDI vs. CVDI +T. Here we report long-term survival results of these pts. Methods: Chemo-naïve pts between 16 and 75 yrs of age, with histologically documented diagnosis of advanced melanoma and without symptomatic brain metastasis, were randomized to receive either CVDI (group A) or CVDI+T (group B). The dose of each drug is as follows: C 15 mg/m2 IV (d 2–5), V 1.2 mg/m2 IV (d 1–5), D 600 mg/m2 IV (d 1), I 5 MU/m2 SQ 3 times a wk and T 20 mg twice a day. The treatment was administered every 3–4 wks. After the interim analysis, the arm with a higher RR was selected for an expansion cohort (group C). The primary endpoint was the RR of CVDI regimen with or without T. The secondary endpoint was overall survival (OS) evaluation. Results: A total of 104 pts were enrolled, among which 36 and 34 were randomized to group A and B, respectively. After interim analysis of 70 pts, the CVDI regimen was selected for group C. There were no significant differences in both RR (p= 0.126) and OS (p= 0.095) between group A and B. When all 104 pt data were combined, the overall response rate (ORR) was 37.5% with a complete response rate (CRR) of 8.7% and the median survival of 10.4 months. One-yr, 2-yr, 5-yr, and 10-yr OS were 43%, 20%, 7% and 4%, respectively. Conclusions: Although the combination of CVDI with or without T is an active regimen for treatment for metastatic melanoma, long-term survival of pts receiving this regimen is similar to historical controls.

[Table: see text]

No significant financial relationships to disclose.

Identification of prognostic factors predictive of CNS metastasis in patients (pts) with advanced unresectable metastatic melanoma (MM)

8060

Background: Diagnosis (Dx) ofCNS metastasis (met) in MM is associated with poor prognosis. The objective of this study was to find prognostic factors that may predict CNS met. Methods: 743 chemotherapy (CRx) naïve MM pts were treated on 12 clinical trials during the past 15 years at MDACC. Demographics, tumor stage, and Rx outcomes were collected. Seven prognostic factors likely to predispose pts to CNS met were assessed: presence of liver met, elevated serum LDH, low serum albumin, site of primary, Clark level ≥ IV / Breslow thickness (BT) > 3.5 mm, M1 stage, and number of visceral met sites. Time to event analyses considered the time from unresectable stage III/ IV disease to Dx of CNS met, or last follow-up if noCNS met. Prognostic factors were examined separately using a Cox proportional hazards model, with time from Dx of primary melanoma to Dx of unresectable stage III/ IV disease also included as a covariate. Estimates of CNS met-free curves were calculated using the Kaplan-Meier product-limit method. The incidence of CNS met between CRx-sensitive and CRx-resistant groups was assessed by Chi-square test. Results: CNS met (n=333) and CNS met-free (n=410) pt groups were similar in median age, gender distribution and primary M sites. Compared to CNS met-free pts, CNS met pts were more likely to have M1b + M1c advanced disease stage (M1b+c 291/333 (87%) vs. 286/410 (70%); p<0.0001) and ≥ 2 visceral met sites (138/333 (41%) vs. 126/410 (30%), p=0.003), as well as greater BT (median 2.3 vs. 1.5 mm). Pts with elevated serum LDH had significantly shorter CNS met-free interval those with normal serum LDH (p=0.0009). CNS met-free interval was also significantly shorter for M1b (p=0.028) and M1c pts (p=0.05), but not M1a (p=0.8) pts, compared to unresectable stage III pts. Compared to pts with soft tissue/l. node disease, CNS met-free interval was significantly shorter for pts with 1–3 met sites (p<0.0001), but not for pts with ≥ 4 sites (p=0.03). The incidence of CNS met was not significantly different between CRx-sensitive and CRx-resistant pts (p=0.2821). Conclusion: Prognostic factors predictive of high risk CNS met were identified that could be used to individualize Rx for MM pts. Supported in part by Chiron Corporation and Carol Courtney Memorial Fund.

No significant financial relationships to disclose.