Although immune checkpoint inhibitors have resulted in durable clinical benefits in a subset of patients with advanced cancer, some patients who did not respond to initial anti–PD-1 therapy have been found to benefit from the addition of salvage chemotherapy. However, the mechanism responsible for the successful chemoimmunotherapy is not completely understood. Here we show that a subset of circulating CD8 + T cells expressing the chemokine receptor CX3CR1 are able to withstand the toxicity of chemotherapy and are increased in patients with metastatic melanoma who responded to chemoimmunotherapy (paclitaxel and carboplatin plus PD-1 blockade). These CX3CR1 + CD8 + T cells have effector memory phenotypes and the ability to efflux chemotherapy drugs via the ABCB1 transporter. In line with clinical observation, our preclinical models identified an optimal sequencing of chemoimmunotherapy that resulted in an increase of CX3CR1 + CD8 + T cells. Taken together, we found a subset of PD-1 therapy–responsive CD8 + T cells that were capable of withstanding chemotherapy and executing tumor rejection with their unique abilities of drug efflux (ABCB1), cytolytic activity (granzyme B and perforin), and migration to and retention (CX3CR1 and CD11a) at tumor sites. Future strategies to monitor and increase the frequency of CX3CR1 + CD8 + T cells may help to design effective chemoimmunotherapy to overcome cancer resistance to immune checkpoint blockade therapy.
Phase II Study of Everolimus in Metastatic Malignant Melanoma (NCCTG-N0377, Alliance)
Abstract Lessons Learned Everolimus does not have sufficient activity to justify its use as single agent in metastatic melanoma. Patients treated with 10 mg per day dose were most likely to require dose reductions. Everolimus appeared to reduce the numbers of regulatory T cells in approximately half of the treated patients; unfortunately, these effects were not correlated with clinical outcomes. Background Everolimus (RAD-001) is an orally active rapamycin analogue shown in preclinical data to produce cytostatic cell inhibition, which may be potentially beneficial in treating melanoma. We conducted a phase II study to evaluate the efficacy and safety of everolimus in patients with unresectable metastatic melanoma (MM). Methods This study included two cohorts; cohort 1 received 30 mg of everolimus by mouth (PO) weekly, and cohort 2 was dosed with 10 mg of everolimus PO daily. The endpoints of the study were safety, 16-week progression-free survival (PFS), overall survival (OS), and measures of immunomodulatory/antiangiogenic properties with therapy. Tumor samples before therapy and at week 8 of treatment were analyzed. Peripheral blood plasma or mononuclear cell isolates collected prior to therapy and at weeks 8 and 16 and at time of tumor progression were analyzed for vascular endothelial growth factor and regulatory T-cell (Treg) measurements. Results A total of 53 patients were enrolled in cohort 1 (n = 24) and cohort 2 (n = 29). Only 2 patients of the first 20 patients enrolled in cohort 2 had treatment responses (25%; 95% confidence interval, 8.6%–49.1%); this result did not allow full accrual to cohort 2, as the study was terminated for futility. Median OS was 12.2 months for cohort 1 versus 8.1 months in cohort 2; no PFS advantage was seen in either group (2.1 months vs. 1.8 months). Dose-limiting toxicities included grade 4 myocardial ischemia (3.4%); grade 3 fatigue, mucositis, and hyperglycemia (10.3%); and anorexia and anemia (6.9%). Everolimus significantly reduced the number of Tregs in approximately half of the treated patients; however, these effects were not correlated with clinical outcomes. Conclusion Everolimus does not have sufficient single-agent activity in MM; however, we have identified evidence of biological activity to provide a potential rationale for future combination studies.
A clinical insight into therapeutic sequence in advanced melanoma.
186 Background: The optimal sequence strategy of BRAF/MEK inhibitors, anti-PD- 1/PDL-1 and anti-CTLA-4 in metastatic BRAF-mutated melanoma patients (pts) is unknown and no treatment guidelines exist. Therefore, we report a single-institution experience of different treatment approaches using targeted therapy (TT) and immunotherapy and its impact on outcomes. Methods: BRAF-mutated metastatic melanoma pts treated with TT and immunotherapy from 2012 to2017 were analyzed. Six groups were identified based on treatment strategy. All time-to-event analyses were calculated using the Kaplan-Meier method and Wilcoxon test. Results: Forty-four pts were identified. The median age at diagnosis was 49 years (range 21-73), 54% pts were females and 43% developed brain metastases during disease course. The most common approach strategy was immunotherapy followed by TT, the median duration of treatment was 11 and 19 weeks, respectively. Time-to-next therapy (TTNT) following 1st line treatment was similar in pts treated with TT (median 23 weeks [95% CI: 15-31]) or immunotherapy (median 26 weeks [95% CI: 10-33], p = 0.94). A trend towards better overall survival (OS) was seen in pts who received immunotherapy followed by TT (p = 0.09); patients who received salvage chemotherapy (carboplatin/paclitaxel) had significantly longer OS (median 7 years [95% CI: 3.2-7.08]) ( p = 0.03). Conclusions: No differences in TTNT were seen with immunotherapy, TT or combined (triple therapy) when used as 1st or 2nd line. The significant longer OS benefit with 1st line immunotherapy was only seen in patients who received chemotherapy later in their treatment course. [Table: see text]
Brief Report: Cancer Immunotherapy in Patients With Preexisting Rheumatic Disease: The Mayo Clinic Experience
ObjectiveTo determine the risk of rheumatic disease flare and adverse effects in patients with preexisting rheumatic disease who were receiving immune checkpoint inhibitor (ICI) therapy.MethodsA retrospective medical record review was performed to identify all patients who received ICI therapy at Mayo Clinic in Rochester, Minnesota between 2011 and 2016 (~700 patients). Those with a preexisting rheumatic disease were identified using specific diagnostic codes.ResultsSixteen patients were identified (81% female, median age 68.5 years). The most common rheumatic diseases were rheumatoid arthritis (n = 5), polymyalgia rheumatica (n = 5), Sjögren's syndrome (n = 2), and systemic lupus erythematosus (n = 2). Seven patients were receiving immunosuppressive therapy or glucocorticoids for their rheumatic disease at the time of initiation of the ICI. The primary malignancies were melanoma (n = 10), pulmonary (n = 4), or hematologic (n = 2). In most cases, ICIs were offered only after failure of several other therapies. Immune‐related adverse effects (IRAEs) occurred in 6 patients, and all were treated successfully with glucocorticoids and discontinuation of the ICI therapy. There were no significant differences in time from cancer diagnosis to immunotherapy, duration of immunotherapy, age, or sex between the patients with and those without IRAEs.ConclusionTo our knowledge, this represents the largest single‐center cohort of patients with rheumatic diseases who were exposed to modern cancer immunotherapy. Only a minority of these patients experienced a flare of their preexisting rheumatic disease or any other IRAE.
Targeting the cyclin dependent kinase and retinoblastoma axis overcomes standard of care resistance in BRAFV600E-mutant melanoma
BackgroundPatients with regionally advanced melanoma are at high risk of distant failure and unlikely to be cured by surgery alone. Neoadjuvant therapy may provide benefit in these patients.ObjectivesTo evaluate our experience with neoadjuvant systemic therapy in high‐risk stage III patients.MethodsRetrospective review of patients with advanced stage III disease who received neoadjuvant therapy between August 2009 and August 2016 at Mayo Clinic Rochester.ResultsTwenty‐three cases met our inclusion criteria, 16 with resectable disease and 7 with unresectable disease. No patients with resectable disease and one patient with borderline resectable disease progressed regionally, prohibiting surgical resection. Five of seven patients with unresectable disease were down‐staged to a resectable state. Six of twenty‐three (26%) had a CR and five are alive at last follow‐up. Fifteen of twenty three patients (65%) progressed with a median progression free survival of 11 months; however, the 5 year overall survival estimate was 84%.ConclusionsNeoadjuvant systemic therapy is a reasonable approach for patients with advanced but resectable/borderline resectable disease and the risk of losing regional control is low. Our data also suggest some patients with unresectable disease will be converted to resectable and a complete clinical response to treatment can be obtained in approximately one quater of patients.
Immune checkpoint molecules soluble program death ligand 1 and galectin‐9 are increased in pregnancy
ProblemPregnancy requires balance between tolerance to the haploidentical fetus and the mother's ability to mount immune responses. There are parallels to this phenomenon that occur in metastatic cancer. We assessed soluble program death ligand‐1 soluble PD‐L1 (sPD‐L1) and galectin‐9 in the blood of pregnant women during gestation as these molecules are highly involved in immune suppression during cancer.Method of studyMaternal blood was collected from 30 primigravida women at monthly intervals during pregnancy, delivery and 6‐week post‐partum. Blood was analyzed for sPD‐L1 and galectin‐9 concentrations by ELISA. Term placentas were collected in formalin and IHC was completed for PD‐L1 and galectin‐9 expression.ResultsMaternal blood levels of sPD‐L1 (0.438 ng/mL) and galectin‐9 (1976 pg/mL) were elevated early in normal pregnancies compared to non‐pregnant controls (0.242 ng/mL and 773 pg/mL, respectively). sPD‐L1 increased throughout gestation, whereas galectin‐9 remained elevated until parturition; both proteins returned to control levels post‐partum. Women carrying male fetuses had significantly higher galectin‐9 levels, but not sPD‐L1, than those carrying females (2263 pg/mL vs 1874 pg/mL; P = .0005). Trophoblast cells of the term placenta coexpress galectin‐9 and PD‐L1.ConclusionImmune‐regulatory molecules galectin‐9 and sPD‐L1 increased during pregnancy and may play a role in immune tolerance that is critical for the fetus.
NCCTG N0879 (Alliance): A randomized phase 2 cooperative group trial of carboplatin, paclitaxel, and bevacizumab ± everolimus for metastatic melanoma