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BACKGROUND: Whether pembrolizumab given both before surgery (neoadjuvant therapy) and after surgery (adjuvant therapy), as compared with pembrolizumab given as adjuvant therapy alone, would increase event-free survival among patients with resectable stage III or IV melanoma is unknown. METHODS: In a phase 2 trial, we randomly assigned patients with clinically detectable, measurable stage IIIB to IVC melanoma that was amenable to surgical resection to three doses of neoadjuvant pembrolizumab, surgery, and 15 doses of adjuvant pembrolizumab (neoadjuvant-adjuvant group) or to surgery followed by pembrolizumab (200 mg intravenously every 3 weeks for a total of 18 doses) for approximately 1 year or until disease recurred or unacceptable toxic effects developed (adjuvant-only group). The primary end point was event-free survival in the intention-to-treat population. Events were defined as disease progression or toxic effects that precluded surgery; the inability to resect all gross disease; disease progression, surgical complications, or toxic effects of treatment that precluded the initiation of adjuvant therapy within 84 days after surgery; recurrence of melanoma after surgery; or death from any cause. Safety was also evaluated. RESULTS: At a median follow-up of 14.7 months, the neoadjuvant-adjuvant group (154 patients) had significantly longer event-free survival than the adjuvant-only group (159 patients) (P = 0.004 by the log-rank test). In a landmark analysis, event-free survival at 2 years was 72% (95% confidence interval [CI], 64 to 80) in the neoadjuvant-adjuvant group and 49% (95% CI, 41 to 59) in the adjuvant-only group. The percentage of patients with treatment-related adverse events of grades 3 or higher during therapy was 12% in the neoadjuvant-adjuvant group and 14% in the adjuvant-only group. CONCLUSIONS: Among patients with resectable stage III or IV melanoma, event-free survival was significantly longer among those who received pembrolizumab both before and after surgery than among those who received adjuvant pembrolizumab alone. No new toxic effects were identified. (Funded by the National Cancer Institute and Merck Sharp and Dohme; S1801 ClinicalTrials.gov number, NCT03698019.).
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Antineoplásicos Imunológicos , Melanoma , Terapia Neoadjuvante , Neoplasias Cutâneas , Humanos , Adjuvantes Imunológicos , Progressão da Doença , Melanoma/tratamento farmacológico , Melanoma/patologia , Melanoma/cirurgia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Quimioterapia AdjuvanteRESUMO
The purpose of this study is to establish the recommended phase 2 dose for regorafenib in combination with sildenafil for patients with advanced solid tumors. Secondary outcomes included identification of antitumor effects of regorafenib and sildenafil, toxicity of the combination, determination of PDE5 expression in tumor samples, and the impact of sildenafil on the pharmacokinetics of regorafenib. This study was a phase 1, open-label single-arm dose-escalation trial using a 3â +â 3 design. Additional patients were enrolled at the maximum tolerated dose (MTD) until a total of 12 patients were treated at the MTD. A total of 29 patients were treated in this study. The median duration of treatment was 8 weeks. The recommended phase 2 doses determined in this study are regorafenib 160â mg daily with sildenafil 100â mg daily. The most common toxicities included palmar-plantar erythrodysesthesia syndrome (20 patients, 69%) and hypophosphatemia (18 patients, 62%). Two patients (7%) experienced grade 4 lipase increase. Objective responses were not observed; however, 14 patients (48%) had a period of stable disease during the study. Stable disease for up to 12 months was observed in patients with ovarian cancer as well as up to 20 months for a patient with cervical cancer. The combination of regorafenib and sildenafil at the recommended phase 2 dose is safe and generally well tolerated. Disease control in patients with gynecologic malignancies was especially encouraging. Further evaluation of the combination of regorafenib and sildenafil in gynecologic malignancies is warranted. Clinical Trial Registration Number: NCT02466802.
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Neoplasias dos Genitais Femininos , Neoplasias , Adulto , Feminino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Genitais Femininos/induzido quimicamente , Neoplasias dos Genitais Femininos/tratamento farmacológico , Dose Máxima Tolerável , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Compostos de Fenilureia/efeitos adversos , Piridinas/uso terapêutico , Citrato de Sildenafila/efeitos adversosRESUMO
Melanoma is among the few cancers that demonstrate an increasing incidence over time. Simultaneously, this trend has been marked by an epidemiologic shift to earlier stage at diagnosis. Before 2011, treatment options were limited for patients with metastatic disease, and the median overall survival was less than 1 year. Since then, the field of melanoma therapeutics has undergone major changes. The use of anti-CTLA-4 and anti-PD1 immune checkpoint inhibitors and combination BRAF/MEK inhibitors for patients with BRAF V600 mutations has significantly extended survival and allowed some patients to remain in durable disease remission off therapy. It has now been confirmed that these classes of agents have a benefit for patients with stage III melanoma after surgical resection, and anti-PD1 and BRAF/MEK inhibitors are standards of care in this setting. Some patients with stage II disease (lymph node-negative; American Joint Committee on Cancer stage IIB and IIC) have worse melanoma-specific survival relative to some patients with stage III disease. Given these results, expanding the population of patients who are considered for adjuvant therapy to include those with stage II melanoma has become a priority, and randomized phase 3 clinical trials are underway. Moving into the future, the validation of patient risk-stratification and treatment-benefit prediction models will be important to improve the number needed to treat and limit exposure to toxicity in the large population of patients with early stage melanoma.
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Antineoplásicos/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/patologia , Estadiamento de Neoplasias/métodos , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Antineoplásicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Quimioterapia Adjuvante , Humanos , Imunoterapia/métodos , Interferons/uso terapêutico , MAP Quinase Quinase 1/antagonistas & inibidores , Ilustração Médica , Melanoma/genética , Melanoma/cirurgia , Recidiva Local de Neoplasia , Números Necessários para Tratar , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Medição de Risco , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Regorafenib is an oral multikinase inhibitor targeting angiogenesis, oncogenesis, and cancer proliferation/metastasis. This study evaluated the efficacy of regorafenib in refractory biliary tract cancer (BTC) in a multi-institutional phase 2 study. METHODS: Patients with BTC who progressed on at least 1 line of systemic therapy received regorafenib at 160 mg daily for 21 days on and 7 days off. The primary endpoint was 6-month overall survival (OS), and the secondary endpoints were median OS, progression-free survival (PFS), and objective response rates. Pretreatment plasma was collected for cytokine evaluation. RESULTS: A total of 39 patients were enrolled, and 33 were evaluable for efficacy. The median PFS and OS were 3.7 and 5.4 months, respectively, with survival rates of 46.2% at 6 months, 35.9% at 12 months, and 25.6% at 18 months for the intention-to-treat population. For the 33 evaluable patients who received regorafenib for at least 3 weeks, the median PFS and OS were 3.9 and 6.7 months, respectively, with survival rates of 51.5% at 6 months, 39.4% at 12 months, and 27.3% at 18 months. The objective response rate was 9.1%, and the disease control rate was 63.6%. Twenty-eight patients (71.8%) experienced grade 3/4 adverse events. Among the 23 cytokines analyzed, elevated baseline vascular endothelial growth factor D (VEGF-D) was associated with shorter PFS, whereas elevated baseline interleukin 6 (IL-6) and glycoprotein 130 (GP130) were associated with shorter OS. CONCLUSIONS: Regorafenib demonstrated modest clinical efficacy in heavily pretreated patients with BTC. Further exploration of biomarkers is warranted to identify a group of patients with BTC who may benefit from regorafenib.
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Neoplasias do Sistema Biliar/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Compostos de Fenilureia/administração & dosagem , Piridinas/administração & dosagem , Fator D de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/efeitos adversos , Neoplasias do Sistema Biliar/epidemiologia , Neoplasias do Sistema Biliar/genética , Neoplasias do Sistema Biliar/patologia , Colangiocarcinoma/epidemiologia , Colangiocarcinoma/patologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Intervalo Livre de Progressão , Piridinas/efeitos adversosRESUMO
BACKGROUND: Clinical variables may correlate with lack of response to treatment (primary resistance) or clinical benefit in patients with clear cell renal cell carcinoma (ccRCC) treated with anti-programmed death 1/ligand one antibodies. METHODS: In this multi-institutional collaboration, clinical characteristics of patients with primary resistance (defined as progression on initial computed tomography scan) were compared to patients with clinical benefit using Two sample t-test and Chi-square test (or Fisher's Exact test). The Kaplan-Meier method was used to estimate the distribution of progression-free survival (PFS) and overall survival (OS) in all patients and the subsets of patients with clinical benefit or primary resistance. Cox's regression model was used to evaluate the correlation between survival endpoints and variables of interest. To explore clinical factors in a larger, independent patient sample, The Cancer Genome Atlas (TCGA) was analyzed. RNAseq gene expression data as well as demographic and clinical information were downloaded for primary tumors of 517 patients included within TCGA-ccRCC. RESULTS: Of 90 patients, 38 (42.2%) had primary resistance and 52 (57.8%) had clinical benefit. Compared with the cohort of patients with initial benefit, primary resistance was more likely to occur in patients with worse ECOG performance status (p = 0.03), earlier stage at diagnosis (p = 0.04), had no prior nephrectomy (p = 0.04) and no immune-related adverse events (irAE) (p = 0.02). In patients with primary resistance, improved OS was significantly correlated with lower International Metastatic RCC Database Consortium risk score (p = 0.02) and lower neutrophil:lymphocyte ratio (p = 0.04). In patients with clinical benefit, improved PFS was significantly associated with increased BMI (p = 0.007) and irAE occurrence (p = 0.02) while improved OS was significantly correlated with overweight BMI (BMI 25-30; p = 0.03) and no brain metastasis (p = 0.005). The cohort TCGA-ccRCC was examined for the correlations between gene expression patterns, clinical factors, and survival outcomes observing associations of T-cell inflammation and angiogenesis signatures with histologic grade, pathologic stage and OS. CONCLUSIONS: Clinical characteristics including performance status, BMI and occurrence of an irAE associate with outcomes in patients with ccRCC treated with immunotherapy. The inverse association of angiogenesis gene signature with ccRCC histologic grade highlight opportunities for adjuvant combination VEGFR2 tyrosine kinase inhibitor and immune-checkpoint inhibition.
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Índice de Massa Corporal , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/terapia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Imunoterapia/efeitos adversos , Neoplasias Renais/genética , Neoplasias Renais/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/imunologia , Bases de Dados Genéticas , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/imunologia , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Linfócitos T/imunologia , Resultado do Tratamento , Adulto JovemRESUMO
The therapeutic landscape for cutaneous melanoma has dramatically advanced in the last several years with the development, validation, and approval by the US Food and Drug Administration of several new therapies that have proven effective in treating metastatic disease. Considerable effort has been put into identifying prognostic and predictive markers of therapeutic response to better delineate the patient populations most likely to benefit from treatment. Baseline tumor burden has been described as a common clinical factor associated with treatment response: lower tumor burden at the time of therapeutic intervention is associated with improved responses and survival outcomes on several therapies. Some therapies have shown efficacy as adjuvant interventions in patients with subclinical disease following definitive treatment, further supporting their role in patients with minimal tumor burden. The increasing evidence that patients with lower tumor burden may be the ones who derive maximal benefit from several melanoma-directed therapies points toward the critical need for risk-tailored surveillance to permit early identification of melanoma metastasis in patients at high risk for recurrence.
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Regorafenib is a multikinase inhibitor with anti-vascular endothelial growth factor receptor (VEGF) activity used as an antiangiogenic agent for metastatic colorectal cancer treatment and has been studied as a potential therapeutic agent for several other cancer treatments. Adverse reactions commonly reported with the use of regorafenib and similar oral multikinase inhibitors include hemorrhage, gastrointestinal fistulas, hypertension, and incomplete wound healing. We report a case of a 59-year-old man with metastatic colorectal adenocarcinoma post-colostomy on regorafenib treatment presenting to the emergency department with altered mental status. MRI showed a left frontoparietal mass, which was resected with a left frontal craniotomy. Postoperative MRI showed a resection cavity without significant hemorrhage. He had been prescribed regorafenib preceding his hospitalization, which was continued after admission before surgery and on postoperative day 1. Thirty-two hours after surgery, the patient exhibited sudden right-sided facial droop and right arm weakness. Imaging revealed an acute intraparenchymal hemorrhage within and adjacent to the tumor resection bed, which was managed conservatively. The patient was subsequently discharged to an inpatient rehabilitation facility. The unusual timing of the hemorrhage suggests that the hemorrhage was due to adverse effects of regorafenib. Patients undergoing neurosurgery should have regorafenib discontinued in preparation for surgery. Similar management should be considered for other anti-VEGF medications to avoid serious complications.
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Here we report the results of a single-center phase 2 clinical trial combining sorafenib tosylate, valproic acid, and sildenafil for the treatment of patients with recurrent high-grade glioma (NCT01817751). Clinical toxicities were grade 1 and grade 2, with one grade 3 toxicity for maculopapular rash (6.4%). For all evaluable patients, the median progression-free survival was 3.65 months and overall survival (OS) 10.0 months. There was promising evidence showing clinical activity and benefit. In the 33 evaluable patients, low protein levels of the chaperone GRP78 (HSPA5) was significantly associated with a better OS (p < 0.0026). A correlation between the expression of PDGFRα and OS approached significance (p < 0.0728). Five patients presently have a mean OS of 73.6 months and remain alive. This is the first therapeutic intervention glioblastoma trial to significantly associate GRP78 expression to OS. Our data suggest that the combination of sorafenib tosylate, valproic acid, and sildenafil requires additional clinical development in the recurrent glioma population.
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New treatments have increased survival of patients with melanoma, and methods to monitor patients throughout the disease process are needed. Circulating tumor DNA (ctDNA) is a predictive and prognostic biomarker that may allow routine, real-time monitoring of disease status. We surveyed 44 US physicians to understand their preferences and practice patterns for biomarker and ctDNA testing in their patients with melanoma. Tumor biomarker testing was often ordered in stage IIIA-IV patients. Barriers to biomarker testing include insufficient tissue (60%) and lack of insurance coverage (54%). ctDNA testing was ordered by 16-18% of physicians for stages II-IV. Reasons for not using ctDNA testing included lack of prospective data (41%), ctDNA testing used for research only (18%), and others. Physicians (≥74%) believed that ctDNA assays could help with monitoring and treatment selection throughout the disease process. Physicians consider ctDNA testing potentially valuable for clinical decision-making but cited concerns that should be addressed.
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DNA Tumoral Circulante , Melanoma , Humanos , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patologia , DNA Tumoral Circulante/genética , Biomarcadores Tumorais/genética , Proteínas Proto-Oncogênicas B-raf/genética , MutaçãoRESUMO
Patients with tumors that do not respond to immune-checkpoint inhibition often harbor a non-T cell-inflamed tumor microenvironment, characterized by the absence of IFN-γ-associated CD8+ T cell and dendritic cell activation. Understanding the molecular mechanisms underlying immune exclusion in non-responding patients may enable the development of novel combination therapies. p38 MAPK is a known regulator of dendritic and myeloid cells however a tumor-intrinsic immunomodulatory role has not been previously described. Here we identify tumor cell p38 signaling as a therapeutic target to potentiate anti-tumor immunity and overcome resistance to immune-checkpoint inhibitors (ICI). Molecular analysis of tumor tissues from patients with human papillomavirus-negative head and neck squamous carcinoma reveals a p38-centered network enriched in non-T cell-inflamed tumors. Pan-cancer single-cell RNA analysis suggests that p38 activation may be an immune-exclusion mechanism across multiple tumor types. P38 knockdown in cancer cell lines increases T cell migration, and p38 inhibition plus ICI in preclinical models shows greater efficacy compared to monotherapies. In a clinical trial of patients refractory to PD1/L1 therapy, pexmetinib, a p38 inhibitor, plus nivolumab demonstrated deep and durable clinical responses. Targeting of p38 with anti-PD1 has the potential to induce the T cell-inflamed phenotype and overcome immunotherapy resistance.
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The number of pregnant women with cancer is on the rise. These patients and their providers encounter complex medical management decisions. Standard-of-care systemic therapy and radiological imaging can impair fetal development and affect viability. Conversely, insufficient monitoring and treatment can lead to cancer progression, compromising the health of the patient. Personalized and tumor-informed circulating tumor DNA (ctDNA) testing (Signatera™, bespoke mPCR NGS assay) is a validated, noninvasive blood test that can accurately assess cancer progression and tumor response to treatment ahead of radiological imaging, across solid tumors. In this case series of four patients, we explore the clinical utility of longitudinal ctDNA testing in the medical management of pregnant patients with solid tumors, to aid in informed decision-making for patients and providers.
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BACKGROUND: The efficacy of cancer immunotherapy can be limited by the poor immunogenicity of cancer and the immunosuppressive tumor microenvironment (TME). Immunologically programming the TME and creating an immune-inflamed tumor phenotype is critical for improving the immune-responsiveness of cancers. Here, we interrogate the immune modulator Flagrp170, engineered via incorporation of a pathogen-associated molecular pattern (ie, flagellin) into an immunostimulatory chaperone molecule, in transforming poorly immunogenic tumors and establishing a highly immunostimulatory milieu for immune augmentation. METHODS: Multiple murine cancer models were used to evaluate the immunostimulatory activity, antitumor potency, and potential side effects of Flagrp170 on administration into the tumors using a replication impaired adenovirus. Antibody neutralization and mice deficient in pattern recognition receptors, that is, toll-like receptor 5 (TLR5) and NOD like receptor (NLR) family caspase activation and recruitment domain (CARD) domain-containing protein 4 (NLRC4), both of which can recognize flagellin, were employed to understand the immunological mechanism of action of the Flagrp170. RESULTS: Intratumoral delivery of mouse or human version of Flagrp170 resulted in robust inhibition of multiple malignancies including head and neck squamous cell carcinoma and breast cancer, without tissue toxicities. This in situ Flagrp170 treatment induced a set of cytokines in the TME known to support Th1/Tc1-dominant antitumor immunity. Additionally, granulocyte macrophage colony-stimulating factor derived from mobilized CD8+ T cells was involved in the therapeutic activity of Flagrp170. We also made a striking finding that NLRC4, not TLR5, is required for Flagrp170-mediated antitumor immune responses. CONCLUSION: Our results elucidate a novel immune-potentiating activity of Flagrp170 via engaging the innate pattern recognition receptor NLRC4, and support its potential clinical use to reshape cancer immune phenotype for overcoming therapeutic resistance.
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Proteínas Reguladoras de Apoptose/genética , Neoplasias da Mama/terapia , Proteínas de Ligação ao Cálcio/genética , Flagelina/genética , Proteínas de Choque Térmico HSP70/genética , Neoplasias de Cabeça e Pescoço/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Adenoviridae/genética , Animais , Anticorpos Neutralizantes/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Flagelina/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Camundongos , Proteínas Recombinantes , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Receptor 5 Toll-Like/genética , Resultado do Tratamento , Microambiente Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: Combination of antiprogrammed cell death protein-1 (PD-1) plus anti-cytotoxic T-cell lymphocyte-4 (anti-CTLA-4) immunotherapy shows greater response rates (RRs) than anti-PD-1 antibody alone in melanoma, but RR after initial anti-PD-1 and programmed death ligand-1 (PD-L1) antibody progression awaits robust investigation. Anti-CTLA-4 antibody alone after anti-PD-1/L1 antibody progression has a historical RR of 13%. We report the results of the first prospective clinical trial evaluating ipilimumab 1 mg/kg plus pembrolizumab following progression on anti-PD-1 immunotherapy. METHODS: Patients with advanced melanoma who had progressed on anti-PD-1/L1 antibody as immediate prior therapy (including non-anti-CTLA-4 antibody combinations) were eligible. Patients received pembrolizumab 200 mg plus ipilimumab 1 mg/kg once every 3 weeks for four doses, followed by pembrolizumab monotherapy. The primary end point was RR by irRECIST. After 35 patients, the trial met the primary end point and was expanded to enroll a total of 70 patients to better estimate the RR. RESULTS: Prior treatments included 60 on anti-PD-1 antibody alone and 10 on anti-PD-1/L1 antibody-based combinations. Thirteen patients had progressed in the adjuvant setting. The median length of prior treatment with anti-PD-1/L1 antibody was 4.8 months. Response assessments included five complete and 15 partial responses, making the irRECIST RR 29% among the entire trial population. The median progression-free survival was 5.0 months, and the median overall survival was 24.7 months. The median duration of response was 16.6 months. There was no difference in median time on prior anti-PD1/L1 or time to PD1 + CTLA4 initiation between responders and nonresponders. Grade 3-4 drug-related adverse events occurred in 27% of patients. Responses occurred in PD-L1-negative, non-T-cell-inflamed, and intermediate tumor phenotypes. CONCLUSION: To our knowledge, this is the first prospective study in melanoma of pembrolizumab plus low-dose ipilimumab after anti-PD-1/L1 immunotherapy failure, demonstrating significant antitumor activity and tolerability.
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Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ipilimumab/uso terapêutico , Melanoma/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Feminino , Humanos , Ipilimumab/farmacologia , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVES: Preclinical data suggest histone deacetylase inhibitors improve the therapeutic index of sorafenib. A phase I study was initiated to establish the recommended phase 2 dose of sorafenib combined with vorinostat in patients with unresectable hepatocellular carcinoma. MATERIALS AND METHODS: Patients received vorinostat (200 to 400 mg by mouth once daily, 5 of 7 d) and sorafenib at standard or reduced doses (400 mg [cohort A] or 200 mg [cohort B] by mouth twice daily). Patients who received 14 days of vorinostat in cycle 1 were evaluable for dose-limiting toxicity (DLT). RESULTS: Sixteen patients were treated. Thirteen patients were evaluable for response. Three patients experienced DLTs, 2 in cohort A (grade [gr] 3 hypokalemia; gr 3 maculopapular rash) and 1 in cohort B (gr 3 hepatic failure; gr 3 hypophosphatemia; gr 4 thrombocytopenia). Eleven patients required dose reductions or omissions for non-DLTtoxicity. Ten patients (77%) had stable disease (SD). The median treatment duration was 4.7 months for response-evaluable patients. One patient with SD was on treatment for 29.9 months, and another patient, also with SD, was on treatment for 18.7 months. Another patient electively stopped therapy after 15 months and remains without evidence of progression 3 years later. CONCLUSIONS: Although some patients had durable disease control, the addition of vorinostat to sorafenib led to toxicities in most patients, requiring dose modifications that prevented determination of the recommended phase 2 dose. The combination is not recommended for further exploration with this vorinostat schedule in this patient population.