Jenny H. Lee

Ipilimumab Therapy in Patients With Advanced Melanoma and Preexisting Autoimmune Disorders

IMPORTANCE Ipilimumab and other immune therapies are effective treatment options for patients with advanced melanoma but cause frequent immune-related toxic effects. Autoimmune diseases are common, and the safety and efficacy of ipilimumab therapy in patients with preexisting autoimmune disorders is not known. OBJECTIVE To determine the safety and efficacy of ipilimumab therapy in patients with advanced melanoma with preexisting autoimmune disorders. DESIGN, SETTING, AND PARTICIPANTS Retrospective review of patients with advanced melanoma and preexisting autoimmune disorders who received ipilimumab at 9 academic tertiary referral centers from January 1, 2012, through August 1, 2015. The data analysis was performed on August 24, 2015. EXPOSURE Ipilimumab therapy. MAIN OUTCOMES AND MEASURES Safety, in terms of frequency of autoimmune flares and conventional immune-related adverse events (irAEs), and efficacy, in terms of response rates and overall survival, were evaluated descriptively. RESULTS Of the 30 patients who received ipilimumab (17 [57%] male; median [range] age, 59.5 [30-80] y), 6 had rheumatoid arthritis, 5 had psoriasis, 6 had inflammatory bowel disease, 2 had systemic lupus erythematosus, 2 had multiple sclerosis, 2 had autoimmune thyroiditis, and 7 had other conditions. Thirteen patients (43%) were receiving immunosuppressive therapy at the time of initiation of ipilimumab therapy, most commonly low-dose prednisone or hydroxychloroquine. With ipilimumab treatment, 8 patients (27%) experienced exacerbations of their autoimmune condition necessitating systemic treatment; all were managed with corticosteroids. Conventional grade 3 to 5 irAEs occurred in 10 patients (33%) and were reversible with corticosteroids or with infliximab therapy in 2 cases. One patient with baseline psoriasis died of presumed immune-related colitis after a 1-week delay prior to reporting symptoms. Fifteen patients (50%) had neither autoimmune disease flares nor irAEs. Six patients experienced an objective response (20%), including 1 with a durable complete response. CONCLUSIONS AND RELEVANCE To our knowledge, this is the largest series of patients with preexisting autoimmune disease treated with immune checkpoint inhibitors. Ipilimumab was clinically active and was associated with exacerbations of autoimmune disease and conventional ipilimumab-induced irAEs that were readily manageable with standard therapies when started in a timely fashion. Ipilimumab therapy may be considered in this setting with vigilant clinical monitoring.

Circulating tumor DNA to monitor treatment response and detect acquired resistance in patients with metastatic melanoma

Repeat tumor biopsies to study genomic changes during therapy are difficult, invasive and data are confounded by tumoral heterogeneity. The analysis of circulating tumor DNA (ctDNA) can provide a non-invasive approach to assess prognosis and the genetic evolution of tumors in response to therapy. Mutation-specific droplet digital PCR was used to measure plasma concentrations of oncogenic BRAF and NRAS variants in 48 patients with advanced metastatic melanoma prior to treatment with targeted therapies (vemurafenib, dabrafenib or dabrafenib/trametinib combination) or immunotherapies (ipilimumab, nivolumab or pembrolizumab). Baseline ctDNA levels were evaluated relative to treatment response and progression-free survival (PFS). Tumor-associated ctDNA was detected in the plasma of 35/48 (73%) patients prior to treatment and lower ctDNA levels at this time point were significantly associated with response to treatment and prolonged PFS, irrespective of therapy type. Levels of ctDNA decreased significantly in patients treated with MAPK inhibitors (p < 0.001) in accordance with response to therapy, but this was not apparent in patients receiving immunotherapies. We show that circulating NRAS mutations, known to confer resistance to BRAF inhibitors, were detected in 3 of 7 (43%) patients progressing on kinase inhibitor therapy. Significantly, ctDNA rebound and circulating mutant NRAS preceded radiological detection of progressive disease. Our data demonstrate that ctDNA is a useful biomarker of response to kinase inhibitor therapy and can be used to monitor tumor evolution and detect the early appearance of resistance effectors.

Circulating tumour DNA predicts response to anti-PD1 antibodies in metastatic melanoma

Background Programmed death 1 (PD1) inhibitors are now a foundation of medical management of metastatic melanoma. This study sought to determine whether circulating tumour DNA (ctDNA) provides useful early response and prognostic information. Patients and methods We evaluated the relationship between pre-treatment and early on treatment ctDNA and outcome in melanoma patients treated with PD1 inhibitors alone or in combination with ipilimumab. Results ctDNA was detected in 40/76 patients (53%) at baseline, and correlated with stage, LDH levels, disease volume and ECOG performance. RECIST response was 72% (26/36) in group A (undetectable ctDNA at baseline), 77% (17/22) in group B (elevated ctDNA at baseline but undetectable within 12 weeks of therapy) and 6% (1/18) in group C (elevated ctDNA at baseline and remained elevated during treatment). The median PFS was not reached in groups A and B and was 2.7 months for group C [hazard ratio (HR) 0.09; P < 0.001 for group A versus C, and 0.16; P < 0.001 for group B versus C]. The median OS was not reached for groups A and B and was 9.2 months for group C (HR 0.02; P < 0.001 for group A versus C and 0.14; P < 0.001 for group B versus C). The poor outcome measures associated with group C remained significant in multivariate analysis adjusted for LDH, performance status, tumour stage and disease volume. The predictive value for ctDNA for response was confirmed in a separate validation cohort (n = 29, P < 0.01). Conclusion Longitudinal assessment of ctDNA in metastatic melanoma patients receiving treatment with PD1 inhibitors is an accurate predictor of tumour response, PFS and OS. Patients who had a persistently elevated ctDNA on therapy had a poor prognosis, and this may guide combination and sequencing of subsequent therapies.

PD-1 and PD-L1 inhibitors in melanoma treatment: past success, present application and future challenges

Anti-programmed death (PD)-1 antibodies have now become the standard of care for advanced melanoma, with two drugs gaining US FDA approval in recent years: nivolumab and pembrolizumab. Both have demonstrated significant activity and durable response with a manageable toxicity profile. Despite initial success, ongoing challenges include patient selection and predictors of response, innate resistance and optimizing combination strategies. In this overview, we take a closer look at the history and development of therapeutic targets to the PD-1/PD-ligand (L)1 pathway, clinical evidence, availability of biomarkers and their limitations in clinical practice and future strategies to improve treatment outcomes.

Liquid biomarkers in melanoma: detection and discovery

A vast array of tumor-derived genetic, proteomic and cellular components are constantly released into the circulation of cancer patients. These molecules including circulating tumor DNA and RNA, proteins, tumor and immune cells are emerging as convenient and accurate liquid biomarkers of cancer. Circulating cancer biomarkers provide invaluable information on cancer detection and diagnosis, prognosticate patient outcomes, and predict treatment response. In this era of effective molecular targeted treatments and immunotherapies, there is now an urgent need to implement use of these circulating biomarkers in the clinic to facilitate personalized therapy. In this review, we present recent findings in circulating melanoma biomarkers, examine the challenges and promise of evolving technologies used for liquid biomarker discovery, and discuss future directions and perspectives in melanoma biomarker research.

Association Between Circulating Tumor DNA and Pseudoprogression in Patients With Metastatic Melanoma Treated With Anti–Programmed Cell Death 1 Antibodies

Importance Longitudinal circulating tumor DNA (ctDNA) has been shown to predict response and survival in patients with metastatic melanoma treated with anti–programmed cell death 1 (PD-1) antibodies. Pseudoprogression, defined as radiologic finding of disease progression prior to response, has been a challenge to clinicians. Objective To establish whether ctDNA at baseline and up to week 12 of treatment can differentiate between the radiologic findings of pseudoprogression and true progression in patients with metastatic melanoma. Design, Setting, and Participants This explorative biomarker study examined circulating BRAF and NRAS mutations in a cohort of 125 patients with melanoma receiving PD-1 antibodies alone or in combination with ipilimumab between July 3, 2014, and May 24, 2016. Pseudoprogression was defined retrospectively as radiologic progression not confirmed as progressive disease at the next radiologic assessment. Plasma samples of ctDNA at baseline and while receiving treatment were taken for analysis prospectively over the first 12 weeks of treatment. Favorable ctDNA profile (undetectable ctDNA at baseline or detectable ctDNA at baseline followed by >10-fold decrease) and unfavorable ctDNA profile (detectable ctDNA at baseline that remained stable or increased) were correlated with response and prognosis. Main Outcomes and Measures Early differentiation of pseudoprogression from true progression using longitudinal ctDNA profile. Results According to guidelines by Response Evaluation Criteria in Solid Tumors (RECIST), progressive disease occurred in 29 of the 125 patients (23.2%). Of the 29 patients, 17 (59%) were 65 years or younger, 18 (62%) were men, 9 (31%) had pseudoprogression, and 20 (69%) had true progression. Of the 9 patients (7%) with confirmed pseudoprogression, all patients had a favorable ctDNA profile. At a median follow-up of 110 weeks, 7 of 9 patients (78%) were alive. All but 2 patients with true progression had an unfavorable ctDNA profile. Sensitivity of ctDNA for predicting pseudoprogression was 90% (95% CI, 68%-99%) and specificity was 100% (95% CI, 60%-100%). The 1-year survival for patients with RECIST-defined progressive disease and favorable ctDNA was 82% vs 39% for unfavorable ctDNA (hazard ratio [HR], 4.8; 95% CI, 1.6-14.3; P = .02). Overall survival was longer in patients with a partial response (54 of 125 patients [43%]) compared with patients with progressive disease and a favorable ctDNA profile (11 of 125 patients [9%]; HR, 0.09; 95% CI, 0.01-0.80; P < .01). Conclusions and Relevance The results demonstrate that ctDNA profiles can accurately differentiate pseudoprogression from true progression of disease in patients with melanoma treated with PD-1 antibodies. Results of this blood test performed at regular intervals during systemic treatment reflect tumor biology and have potential as a powerful biomarker to predict long-term response and survival.

Evaluation of two high-throughput proteomic technologies for plasma biomarker discovery in immunotherapy-treated melanoma patients

BackgroundSelective kinase and immune checkpoint inhibitors, and their combinations, have significantly improved the survival of patients with advanced metastatic melanoma. Not all patients will respond to treatment however, and some patients will present with significant toxicities. Hence, the identification of biomarkers is critical for the selection and management of patients receiving treatment. Biomarker discovery often involves proteomic techniques that simultaneously profile multiple proteins but few studies have compared these platforms.MethodsIn this study, we used the multiplex bead-based Eve Technologies Discovery assay and the aptamer-based SomaLogic SOMAscan assay to identify circulating proteins predictive of response to immunotherapy in melanoma patients treated with combination immune checkpoint inhibitors. Expression of four plasma proteins were further validated using the bead-based Millipore Milliplex assay.ResultsBoth the Discovery and the SOMAscan assays detected circulating plasma proteins in immunotherapy-treated melanoma patients. However, these widely used assays showed limited correlation in relative protein quantification, due to differences in specificity and the dynamic range of protein detection. Protein data derived from the Discovery and Milliplex bead-based assays were highly correlated.ConclusionsOur study highlights significant limitations imposed by inconsistent sensitivity and specificity due to differences in the detection antibodies or aptamers of these widespread biomarker discovery approaches. Our findings emphasize the need to improve these technologies for the accurate identification of biomarkers.

Metastasis-specific patterns of response and progression with anti-PD-1 treatment in metastatic melanoma

This study evaluated patterns of response as discerned by comprehensive metastasis‐specific analysis in metastatic melanoma patients receiving anti‐PD‐1 antibodies. Bi‐dimensional measurements of every metastasis in patients enrolled in the KEYNOTE‐001 trial at a single institution were obtained at baseline and throughout treatment. Twenty‐seven evaluable patients had 399 baseline metastases measurable on CT imaging. Complete response (CR) which occurred in 52.6% of metastases was smaller (mean 223 mm2 versus 760 mm2, p < .01) and occurred more frequently in the lungs (65% versus 39.4%, p < .01). Response was heterogenous (new/progressing metastases alongside CR metastases) at first assessment in 4/14 patients with objective response (OR) as opposed to 7/13 patients with non‐OR. CR of individual metastases is common and influenced by site and size. Most patients with OR demonstrate homogenous regression in all metastases at the first assessment. In contrast, patients with early heterogeneity had a poor outcome.

Evaluation of commercial kits for purification of circulating free DNA

Analysis of liquid biopsies and the identification of non-invasive biomarkers for the diagnosis and prognosis of solid tumors has grown exponentially over the last few years. This has led to an increasing number of commercial kits optimised for the purification of circulating free (cf) DNA and RNA/miRNA from biofluids such as plasma, serum and urine. To optimise and standardise current practices we sought to evaluate the performance of spin column-based and magnetic bead-based commercial kits. The following commercial cfDNA purification kits were analysed in this study: QIAamp circulating nucleic acid kit (Qiagen, Germany); Plasma/serum cell-free circulating DNA Purification midi kit (Norgen Biotek, Canada); QIAamp minElute ccfDNA mini kit (Qiagen); Maxwell RSC ccfDNA plasma kit (Promega, USA); MagMAX cell-free DNA isolation kit (Applied Biosystems, USA); and NextPrep-Mag cfDNA isolation kit (Bioo Scientific, USA). Extracted DNA from the plasma of healthy individuals, either nonspiked or spiked with DNA fragments or cfDNA, was evaluated for recovery using either a BioRad Experion or ddPCR analysis. This study represents the first to use a comprehensive size distribution of spiked-in DNA fragments to evaluate commercial cfDNA kits. The commonly used spin column-based Qiagen QIAamp circulating nucleic acid kit was found to be the most consistent performing kit across the two evaluation assays employed. The Qiagen QIAamp minElute ccfDNA mini kit represented the best performing magnetic bead-based kit and provides an alternative based on lower cost/sample with a simpler workflow than spin column-based kits.