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Oncotarget May 2020Multiple myeloma (MM) is the second most common hematologic malignancy. While major advances have been made in the disease, it is still incurable. Although...
Multiple myeloma (MM) is the second most common hematologic malignancy. While major advances have been made in the disease, it is still incurable. Although antifolate-based drugs are not commonly used to treat myeloma, new generation analogs with distinct patterns of preclinical and clinical activity may offer an opportunity to identify new classes of potentially active drugs. Pralatrexate (PDX), which was approved for the treatment of relapsed or refractory peripheral T-cell lymphoma in 2009, may be one such drug. Pralatrexate exhibits a potency and pattern of activity distinct from its predecessors like methotrexate (MTX). We sought to understand the activity and mechanisms of resistance of multiple myeloma to these drugs, which could also offer potential strategies for selective use of the drug. We demonstrate that PDX and MTX both induce a significant decrease in cell viability in the low nanomolar range, with PDX exhibiting a more potent effect. We identified a series of myeloma cell lines exhibiting markedly different patterns of sensitivity to the drugs, with some lines frankly resistant, and others exquisitely sensitive. These differences were largely attributed to the basal RFC (Reduced Folate Carrier) mRNA expression levels. RFC mRNA expression correlated directly with rates of drug uptake, with the most sensitive lines exhibiting the most significant intracellular accumulation of pralatrexate. This mechanism explains the widely varying patterns of sensitivity and resistance to pralatrexate in multiple myeloma cell lines. These findings could have implications for this class of drugs and their role in the treatment of multiple myeloma.
PubMed: 32405334
DOI: 10.18632/oncotarget.27516 -
Therapeutics and Clinical Risk... 2011Aggressive T cell lymphomas are a subgroup of lymphomas with a particularly poor prognosis. This is especially true for patients with recurrent or refractory disease,...
Aggressive T cell lymphomas are a subgroup of lymphomas with a particularly poor prognosis. This is especially true for patients with recurrent or refractory disease, who typically have limited response to salvage therapy and extremely poor overall survival. For this reason, there is a strong need to develop potentially active drugs for these malignancies. Pralatrexate is a novel antifolate designed to have high affinity for reduced folate carrier type 1. Preclinical and clinical studies have demonstrated that pralatrexate has significant activity against T cell lymphomas. The dose-limiting toxicity for pralatrexate is mucositis, which can be abrogated with folic acid and vitamin B12 supplementation. Pralatrexate is the first single agent approved for the treatment of patients with relapsed or refractory peripheral T cell lymphoma. This approval was based on an overall objective response rate observed in the pivotal study. The overall response rate was 29%, with a median duration of 10.1 months. This article reviews the biochemistry, preclinical experience, metabolism, and pharmacokinetics of pralatrexate, including the clinical experience with this agent in lymphoma. Future areas of development are now focused on identifying synergistic combinations of pralatrexate with other agents and the evaluation of predictive markers for clinical benefit.
PubMed: 22076116
DOI: 10.2147/TCRM.S22834 -
The Journal of Dermatology May 2021Pralatrexate has been approved for the treatment of relapsed/refractory peripheral T cell lymphomas. Studies in the U.S. also support the clinical efficacy of...
Pralatrexate has been approved for the treatment of relapsed/refractory peripheral T cell lymphomas. Studies in the U.S. also support the clinical efficacy of pralatrexate to treat advanced-stage cutaneous T-cell lymphomas, but outcomes in Japanese patients have not yet been reported. We herein describe two Japanese patients with heavily-pretreated relapsed/refractory mycosis fungoides that were successfully controlled by pralatrexate.
Topics: Aminopterin; Humans; Japan; Mycosis Fungoides; Neoplasm Recurrence, Local; Skin Neoplasms
PubMed: 33454985
DOI: 10.1111/1346-8138.15761 -
Journal of Thoracic Oncology : Official... Nov 2011Pralatrexate is an antifolate designed for preferential tumor cell uptake and accumulation and received accelerated Food and Drug Administration approval in...
INTRODUCTION
Pralatrexate is an antifolate designed for preferential tumor cell uptake and accumulation and received accelerated Food and Drug Administration approval in relapsed/refractory peripheral T-cell lymphoma. Pralatrexate 135 to 150 mg/m(2) every 2 weeks without vitamin supplementation was active in non-small cell lung cancer (NSCLC) although mucositis was dose limiting. This phase 1 study evaluated the safety of higher pralatrexate doses with vitamin supplementation to minimize toxicities.
METHODS
Patients with stage IIIB/IV NSCLC received pralatrexate 150 to 325 mg/m(2) every 2 weeks with folic acid and vitamin B12 supplementation. Outcomes measured included adverse events (AEs), pharmacokinetics, and radiologic response.
RESULTS
Thirty-nine patients were treated for a median of two cycles (range 1-16+). Common treatment-related grade 3 and 4 AEs by dose (≤190 mg/m(2) and >190 mg/m(2)) included mucositis (33 and 40%) and fatigue (11 and 17%). Treatment-related serious AE (SAE) rates for doses ≤190 and >190 mg/m(2) were 0 and 20%, respectively. The response rate was 10% (95% confidence interval: 1-20%), including two patients with complete response (26+ and 32+ months) and two with partial response. Serum pralatrexate concentrations increased dose dependently up to 230 mg/m(2).
CONCLUSIONS
Pralatrexate with vitamin supplementation was safely administered to patients with previously treated NSCLC, and durable responses were observed. The recommended starting dose for phase 2 is 190 mg/m(2). A similar safety profile was observed in patients treated at 230 mg/m(2), although a higher serious AE rate was evident. Mucositis remains the dose-limiting toxicity of pralatrexate, and this study failed to demonstrate that vitamin supplementation prevents mucositis and failed to identify clinical predictors of mucositis. Individualized dose-modification strategies and prospective mucositis management will be necessary in future trials.
Topics: Adenocarcinoma; Aged; Aminopterin; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Carcinoma, Squamous Cell; Dietary Supplements; Female; Folic Acid; Folic Acid Antagonists; Humans; Lung Neoplasms; Male; Maximum Tolerated Dose; Middle Aged; Prognosis; Tissue Distribution; Vitamin B 12; Vitamin B Complex
PubMed: 21841501
DOI: 10.1097/JTO.0b013e31822adb19 -
Clinical Cancer Research : An Official... Jul 2017Pralatrexate is a folic acid analogue metabolic inhibitor similar to methotrexate, which has shown tolerability and efficacy with an overall response rate of 45% in a...
Pralatrexate is a folic acid analogue metabolic inhibitor similar to methotrexate, which has shown tolerability and efficacy with an overall response rate of 45% in a phase I dose deescalation study of patients with relapsed/refractory cutaneous T-cell lymphoma (CTCL). The object of this phase I/II open-label, multicenter clinical trial was to determine the MTD and recommended dose of pralatrexate plus oral bexarotene in 34 patients with relapsed/refractory CTCL who had failed prior systemic therapies. Pralatrexate was administered by intravenous push at 15 mg/m given weekly 3 weeks out of 4 weeks with daily oral bexarotene (150 or 300 mg/m), levothyroxine, atorvastatin, folate, and with B12 every 2 months. At the MTD of 15 mg/m bexarotene and 15 mg/m pralatrexate, the response rate was 60% [4 complete responses (CR), 14 partial responses (PR)], the maximum observed response duration was 28.9+ months, and duration of response for 4 CRs ranged from 9.0 to 28.3 months. The median progression-free survival was 12.8 months (0.5-29.9). Mucositis was the most common adverse event. The combination of pralatrexate (15 mg/m) and oral bexarotene (150 mg/m) is active with high response rates and minimal toxicity for cutaneous T-cell lymphomas. .
Topics: Adult; Aged; Aged, 80 and over; Aminopterin; Antineoplastic Combined Chemotherapy Protocols; Bexarotene; Disease-Free Survival; Dose-Response Relationship, Drug; Female; Humans; Lymphoma, T-Cell, Cutaneous; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Recurrence, Local; Tetrahydronaphthalenes; Treatment Outcome
PubMed: 28167509
DOI: 10.1158/1078-0432.CCR-16-2064 -
Blood Jan 2018
Topics: Aminopterin; Depsipeptides; Humans; Lymphoma, T-Cell; Lymphoma, T-Cell, Peripheral
PubMed: 29371206
DOI: 10.1182/blood-2017-11-817734 -
Therapeutic Advances in Hematology Aug 2012T-cell lymphomas (TCL) are a diverse and heterogeneous group of malignancies that represent less than 15% of all non-Hodgkin lymphomas. Initial refinements of the...
T-cell lymphomas (TCL) are a diverse and heterogeneous group of malignancies that represent less than 15% of all non-Hodgkin lymphomas. Initial refinements of the clinical classification of these complex diseases have been made, but a better understanding of their molecular pathogenesis is still needed. Even if the paucity of insights into the underlying pathogenesis of TCLs has hindered our ability to develop rational targeted therapies, significant advances have been made. Pralatrexate (10-propargyl 10-deazaaminopterin) is a unique antifolate that has been rationally designed to have high affinity for the reduced folate receptor (RFC) and the folylpolyglutamate synthetase (FPGS) and was the first drug ever approved for the treatment of relapsed and refractory peripheral T-cell lymphomas (PTCL). This review describes the preclinical development of pralatrexate that led to early-phase clinical trials in lung cancer and lymphoma and its subsequent approval in PTCL. The review also describes how pralatrexate has been combined with other agents in both the preclinical and clinical settings. FDA approval for the use of pralatrexate in PTCL has been granted based on the results of the pivotal Phase II trial of this agent in relapsed and refractory PTCL patients. clinical development, pralatrexate, preclinical data, T-cell lymphoma.
PubMed: 23606933
DOI: 10.1177/2040620712445330 -
The Journal of Clinical Endocrinology... Sep 2021Despite the use of aggressive multimodality treatment, most anaplastic thyroid carcinoma (ATC) patients die within a year of diagnosis. Although the combination of BRAF...
BACKGROUND
Despite the use of aggressive multimodality treatment, most anaplastic thyroid carcinoma (ATC) patients die within a year of diagnosis. Although the combination of BRAF and MEK inhibitors has recently been approved for use in BRAF-mutated ATC, they remain effective in a minority of patients who are likely to develop drug resistance. There remains a critical clinical need for effective systemic agents for ATC with a reasonable toxicity profile to allow for rapid translational development.
MATERIAL AND METHODS
Twelve human thyroid cancer cell lines with comprehensive genomic characterization were used in a high-throughput screening (HTS) of 257 compounds to select agents with maximal growth inhibition. Cell proliferation, colony formation, orthotopic thyroid models, and patient-derived xenograft (PDX) models were used to validate the selected agents.
RESULTS
Seventeen compounds were effective, and docetaxel, LBH-589, and pralatrexate were selected for additional in vitro and in vivo analysis as they have been previously approved by the US Food and Drug Administration for other cancers. Significant tumor growth inhibition (TGI) was detected in all tested models treated with LBH-589; pralatrexate demonstrated significant TGI in the orthotopic papillary thyroid carcinoma model and 2 PDX models; and docetaxel demonstrated significant TGI only in the context of mutant TP53.
CONCLUSIONS
HTS identified classes of systemic agents that demonstrate preferential effectiveness against aggressive thyroid cancers, particularly those with mutant TP53. Preclinical validation in both orthotopic and PDX models, which are accurate in vivo models mimicking tumor microenvironment, may support initiation of early-phase clinical trials in non-BRAF mutated or refractory to BRAF/MEK inhibition ATC.
Topics: Animals; Antineoplastic Agents; Carcinogenicity Tests; Cell Line, Tumor; Disease Models, Animal; High-Throughput Screening Assays; Humans; Protein Kinase Inhibitors; Proto-Oncogene Proteins B-raf; Thyroid Carcinoma, Anaplastic; Thyroid Neoplasms; Tumor Microenvironment
PubMed: 34120183
DOI: 10.1210/clinem/dgab424 -
Journal of Clinical and Experimental... 2020
Relapsed refractory nodal peripheral T-cell lymphoma with follicular helper T-cell phenotype was initially resistant to pralatrexate and confirmed to be unresponsive to subsequent forodesine, but responded to re-instituted pralatrexate.
Topics: Aged; Aminopterin; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Cyclophosphamide; Doxorubicin; Female; Humans; Lymph Nodes; Lymphoma, T-Cell, Peripheral; Neoplasm Recurrence, Local; Prednisone; Purine Nucleosides; Pyrimidinones; T-Lymphocytes, Helper-Inducer; Vincristine
PubMed: 32224563
DOI: 10.3960/jslrt.18031 -
Cancer Chemotherapy and Pharmacology Nov 2014To investigate the ability of leucovorin (LV) to abrogate dose-limiting toxicities of pralatrexate (PDX) while maintaining efficacy, in vivo.
PURPOSE
To investigate the ability of leucovorin (LV) to abrogate dose-limiting toxicities of pralatrexate (PDX) while maintaining efficacy, in vivo.
METHODS
H2052 mesothelioma cells were treated with the antifolates methotrexate (MTX), PDX and pemetrexed, with and without LV rescue 24 h later. Cell killing was evaluated 48 h later. Female nude mice bearing H2052 xenografts were treated with varying doses and schedules of the antifolate PDX and LV.
RESULTS
In vitro, H2052 cells were more sensitive to PDX as compared to MTX and pemetrexed. Administration of LV 24 h after antifolate treatment reduced efficacy of antifolates MTX and pemetrexed, but not PDX. In vivo, LV was found to reduce toxicity of PDX at the maximum tolerated dose without sacrificing efficacy. Lethal doses of PDX were rescued by LV, and mice bearing the H2052 tumor demonstrated prolonged and enhanced tumor regression.
CONCLUSIONS
High-dose PDX with subsequent LV rescue may be a viable treatment strategy in mesothelioma and other cancers. The inclusion of LV rescue into new and existing PDX treatment protocols should be explored as a way to expand the tolerability and effectiveness of PDX in the clinic.
Topics: Aminopterin; Animals; Antineoplastic Combined Chemotherapy Protocols; Body Weight; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Drug Synergism; Female; Folic Acid Antagonists; Glutamates; Guanine; Humans; Leucovorin; Mesothelioma; Methotrexate; Mice, Nude; Pemetrexed; Time Factors; Tumor Burden; Vitamin B Complex; Xenograft Model Antitumor Assays
PubMed: 25205429
DOI: 10.1007/s00280-014-2580-z