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Frontiers in Cellular and Infection... 2023The APLICOV-PC study assessed the safety and preliminary efficacy of plitidepsin in hospitalized adult patients with COVID-19. In this follow-up study (E-APLICOV), the...
INTRODUCTION
The APLICOV-PC study assessed the safety and preliminary efficacy of plitidepsin in hospitalized adult patients with COVID-19. In this follow-up study (E-APLICOV), the incidence of post-COVID-19 morbidity was evaluated and any long-term complications were characterized.
METHODS
Between January 18 and March 16, 2022, 34 of the 45 adult patients who received therapy with plitidepsin in the APLICOV-PC study were enrolled in E-APLICOV (median time from plitidepsin first dose to E-APLICOV enrollment, 16.8 months [range, 15.2-19.5 months]). All patients were functionally autonomous with regard to daily living (Barthel index: 100) and had normal physical examinations.
RESULTS
From the APLICOV-PC date of discharge to the date of the extension visit, neither Common Terminology Criteria for Adverse Events version 5.0 (CTCAE v5) grade 3-4 complications nor QT prolongation or significant electrocardiogram (EKG) abnormalities were reported. Five (14.7%) patients had another COVID-19 episode after initial discharge from APLICOV-PC, and in 2 patients (5.9%), previously unreported chest X-ray findings were documented. Spirometry and lung-diffusion tests were normal in 29 (85.3%) and 27 (79.4%) patients, respectively, and 3 patients needed additional oxygen supplementation after initial hospital discharge. None of these patients required subsequent hospital readmission for disease-related complications.
DISCUSSION
In conclusion, plitidepsin has demonstrated a favorable long-term safety profile in adult patients hospitalized for COVID-19. With the constraints of a low sample size and a lack of control, the rate of post-COVID-19 complications after treatment with plitidepsin is in the low range of published reports. (ClinicalTrials.gov Identifier: NCT05121740; https://clinicaltrials.gov/ct2/show/NCT05121740).
Topics: Humans; Adult; COVID-19; Follow-Up Studies; SARS-CoV-2; Hospitals; Treatment Outcome
PubMed: 36909731
DOI: 10.3389/fcimb.2023.1097809 -
Marine Drugs Jan 2014The prevailing paradigm states that cancer cells acquire multiple genetic mutations in oncogenes or tumor suppressor genes whose respective activation/up-regulation or... (Review)
Review
The prevailing paradigm states that cancer cells acquire multiple genetic mutations in oncogenes or tumor suppressor genes whose respective activation/up-regulation or loss of function serve to impart aberrant properties, such as hyperproliferation or inhibition of cell death. However, a tumor is now considered as an organ-like structure, a complex system composed of multiple cell types (e.g., tumor cells, inflammatory cells, endothelial cells, fibroblasts, etc.) all embedded in an inflammatory stroma. All these components influence each other in a complex and dynamic cross-talk, leading to tumor cell survival and progression. As the microenvironment has such a crucial role in tumor pathophysiology, it represents an attractive target for cancer therapy. In this review, we describe the mechanism of action of trabectedin and plitidepsin as an example of how these specific drugs of marine origin elicit their antitumor activity not only by targeting tumor cells but also the tumor microenvironment.
Topics: Animals; Antineoplastic Agents; Aquatic Organisms; Cell Death; Cell Survival; Depsipeptides; Dioxoles; Disease Progression; Humans; Molecular Targeted Therapy; Neoplasms; Peptides, Cyclic; Tetrahydroisoquinolines; Trabectedin; Tumor Microenvironment
PubMed: 24473171
DOI: 10.3390/md12020719 -
MedRxiv : the Preprint Server For... May 2021Plitidepsin is a marine-derived cyclic-peptide that inhibits SARS-CoV-2 replication at low nanomolar concentrations by the targeting of host protein eEF1A (eukaryotic...
UNLABELLED
Plitidepsin is a marine-derived cyclic-peptide that inhibits SARS-CoV-2 replication at low nanomolar concentrations by the targeting of host protein eEF1A (eukaryotic translation-elongation-factor-1A). We evaluated a model of intervention with plitidepsin in hospitalized COVID-19 adult patients where three doses were assessed (1.5, 2 and 2.5 mg/day for 3 days, as a 90-minute intravenous infusion) in 45 patients (15 per dose-cohort). Treatment was well tolerated, with only two Grade 3 treatment-related adverse events observed (hypersensitivity and diarrhea). The discharge rates by Days 8 and 15 were 56.8% and 81.8%, respectively, with data sustaining dose-effect. A mean 4.2 log10 viral load reduction was attained by Day 15. Improvement in inflammation markers was also noted in a seemingly dose-dependent manner. These results suggest that plitidepsin impacts the outcome of patients with COVID-19.
ONE-SENTENCE SUMMARY
Plitidepsin, an inhibitor of SARS-Cov-2 , is safe and positively influences the outcome of patients hospitalized with COVID-19.
PubMed: 34075384
DOI: 10.1101/2021.05.25.21257505 -
Anticancer Research Sep 2021To evaluate the antitumor effects of Plitidepsin against clear cell carcinoma (CCC) of the ovary.
BACKGROUND/AIM
To evaluate the antitumor effects of Plitidepsin against clear cell carcinoma (CCC) of the ovary.
MATERIALS AND METHODS
The expression of eEF1A2 in ovarian cancer was assessed by immunohistochemistry. Using ovarian CCC cell lines, the antitumor effect of Plitidepsin was assessed both in vitro and in vivo. By over-expressing or knocking down the eEF1A2 expression, we investigated the role of eEF1A2 in the sensitivity of CCC cells to Plitidepsin.
RESULTS
Immunoreactivity to eEF1A2 was observed in 76.2% of CCC, which was significantly higher than other histological subtypes of ovarian cancer. Plitidepsin exhibited significant antitumor activity toward chemonaive and chemoresistant CCC cells both in vitro and in vivo. Ectopic expression of eEF1A2 in CCC cells resulted in increased sensitivity to Plitidepsin. In contrast, eEF1A2 knockdown decreased sensitivity of CCC cells to plitidepsin.
CONCLUSION
Plitidepsin, a novel anti-cancer agent that targets eEF1A2, may be a promising agent for treating ovarian CCC.
Topics: Adenocarcinoma, Clear Cell; Animals; Cell Line, Tumor; Cell Proliferation; Cisplatin; Depsipeptides; Drug Resistance, Neoplasm; Female; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Humans; Mice; Ovarian Neoplasms; Peptide Elongation Factor 1; Peptides, Cyclic; Up-Regulation; Xenograft Model Antitumor Assays
PubMed: 34475047
DOI: 10.21873/anticanres.15232 -
Antiviral Research Apr 2022The pandemic caused by the new coronavirus SARS-CoV-2 has made evident the need for broad-spectrum, efficient antiviral treatments to combat emerging and re-emerging...
The pandemic caused by the new coronavirus SARS-CoV-2 has made evident the need for broad-spectrum, efficient antiviral treatments to combat emerging and re-emerging viruses. Plitidepsin is an antitumor agent of marine origin that has also shown a potent pre-clinical efficacy against SARS-CoV-2. Plitidepsin targets the host protein eEF1A (eukaryotic translation elongation factor 1 alpha) and affects viral infection at an early, post-entry step. Because electron microscopy is a valuable tool to study virus-cell interactions and the mechanism of action of antiviral drugs, in this work we have used transmission electron microscopy (TEM) to evaluate the effects of plitidepsin in SARS-CoV-2 infection in cultured Vero E6 cells 24 and 48h post-infection. In the absence of plitidepsin, TEM morphological analysis showed double-membrane vesicles (DMVs), organelles that support coronavirus genome replication, single-membrane vesicles with viral particles, large vacuoles with groups of viruses and numerous extracellular virions attached to the plasma membrane. When treated with plitidepsin, no viral structures were found in SARS-CoV-2-infected Vero E6 cells. Immunogold detection of SARS-CoV-2 nucleocapsid (N) protein and double-stranded RNA (dsRNA) provided clear signals in cells infected in the absence of plitidepsin, but complete absence in cells infected and treated with plitidepsin. The present study shows that plitidepsin blocks the biogenesis of viral replication organelles and the morphogenesis of virus progeny. Electron microscopy morphological analysis coupled to immunogold labeling of SARS-CoV-2 products offers a unique approach to understand how antivirals such as plitidepsin work.
Topics: Animals; Antiviral Agents; Chlorocebus aethiops; Depsipeptides; Peptides, Cyclic; SARS-CoV-2; Vero Cells; Virus Replication; COVID-19 Drug Treatment
PubMed: 35231500
DOI: 10.1016/j.antiviral.2022.105270 -
Journal of Hematology & Oncology Jan 2022There is an urgent need for highly efficacious antiviral therapies in immunosuppressed hosts who develop coronavirus disease (COVID-19), with special concern for those...
Plitidepsin as a successful rescue treatment for prolonged viral SARS-CoV-2 replication in a patient with previous anti-CD20 monoclonal antibody-mediated B cell depletion and chronic lymphocytic leukemia.
BACKGROUND
There is an urgent need for highly efficacious antiviral therapies in immunosuppressed hosts who develop coronavirus disease (COVID-19), with special concern for those affected by hematological malignancies.
CASE PRESENTATION
Here, we report the case of a 75-year-old male with chronic lymphocytic leukemia who was deficient in CD19CD20 B-lymphocyte populations due to previous treatment with anti-CD20 monoclonal antibodies. The patient presented with severe COVID-19 pneumonia due to prolonged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and was treated with two courses of the antiviral plitidepsin on a compassionate use basis. The patient subsequently achieved an undetectable viral load, and his pneumonia resolved.
CONCLUSIONS
Treatment with plitidepsin was well-tolerated without any further hematological or cardiovascular toxicities. This case further supports plitidepsin as a potential antiviral drug in SARS-CoV-2 patients affected by immune deficiencies and hematological malignancies.
Topics: Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antigens, CD20; B-Lymphocytes; COVID-19; Depsipeptides; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Lymphocyte Depletion; Male; Peptides, Cyclic; SARS-CoV-2; Treatment Outcome; Virus Replication
PubMed: 35012608
DOI: 10.1186/s13045-021-01220-0 -
Clinical Cancer Research : An Official... Nov 2005Undifferentiated (anaplastic) thyroid carcinoma is a highly aggressive human cancer with very poor prognosis. Although there have been a few studies of candidate...
Undifferentiated (anaplastic) thyroid carcinoma is a highly aggressive human cancer with very poor prognosis. Although there have been a few studies of candidate treatments, the fact that it is an infrequent tumor makes it very difficult to design clinical trials. A strong association has been observed between undifferentiated thyroid carcinoma and TP53 mutations in numerous molecular genetic and expression studies. Plitidepsin (Aplidin, PharmaMar, Madrid, Spain) is a novel anticancer compound obtained from a sea tunicate. This compound has been reported to induce apoptosis independently of TP53 status. We investigated the actions of plitidepsin in human thyroid cancer cells. In initial experiments using primary cultured cells from a differentiated (papillary) carcinoma, we found that 100 nmol/L plitidepsin induced apoptosis, whereas lower doses were cytostatic. Because our aim was to study the effects of plitidepsin at clinically relevant concentrations, subsequent experiments were done with a dosage regimen reflecting plasma concentrations observed in previously reported clinical trials: 100 nmol/L for 4 hours, followed by 10 nmol/L for 20 hours (4(100)/20(10) plitidepsin). This plitidepsin dosage regimen blocked the proliferation of a primary undifferentiated/anaplastic thyroid carcinoma culture obtained in our laboratory and of a commercial cell line (8305C) obtained from an undifferentiated thyroid carcinoma; however, it did not induce apoptosis. The proportion of cells in the G(1) phase of the cell cycle was greatly increased and the proportion in the S/G(2)-M phases greatly reduced, suggesting that plitidepsin blocks G(1)-to-S transition. Levels of the cyclin D1/cyclin-dependent kinase 4/p21 complex proteins were decreased and, in line with this, the levels of unphosphorylated Rb1 increased. The decrease in cell cycle proteins correlated with hypoacetylation of histone H3. Finally, we did experiments to assess how rapidly tumor cells return to their initial pretreatment proliferative behavior after 4(100)/20(10) plitidepsin treatment. Cells from undifferentiated tumors needed more than 3 days to recover logarithmic growth, and after 7 days, cell number was still significantly lower than in control cultures. 4(100)/20(10) plitidepsin inhibited the growth in soft agar. Together, our data show that plitidepsin is able to block in vitro cell cycle progression at concentrations similar to serum concentrations observed in vivo, and that this effect is persistent for several days after plitidepsin removal. Whether plitidepsin will prove to be clinically useful in the treatment of undifferentiated thyroid cancers remains to be established. However, our results raise the possibility that plitidepsin might be effective alone or in combination with radiotherapy and/or other drug treatments.
Topics: Adult; Agar; Aged; Antineoplastic Agents; Apoptosis; Carcinoma; Cell Cycle; Cell Differentiation; Cell Line, Tumor; Cell Proliferation; Clinical Trials as Topic; Depsipeptides; Dose-Response Relationship, Drug; Female; Flow Cytometry; Gene Expression Regulation, Neoplastic; Genes, p53; HeLa Cells; Histones; Humans; Immunoblotting; Male; Middle Aged; Models, Statistical; Peptides, Cyclic; Thyroid Gland; Thyroid Neoplasms; Time Factors; Tumor Cells, Cultured; Tumor Suppressor Protein p53
PubMed: 16278386
DOI: 10.1158/1078-0432.CCR-05-0455 -
Annals of Oncology : Official Journal... Oct 2021
Topics: Antineoplastic Agents; Depsipeptides; Humans; Neoplasms; Peptides, Cyclic; COVID-19 Drug Treatment
PubMed: 34242743
DOI: 10.1016/j.annonc.2021.07.003 -
Cell Oct 2023SARS-CoV-2 variants of concern (VOCs) emerged during the COVID-19 pandemic. Here, we used unbiased systems approaches to study the host-selective forces driving VOC...
SARS-CoV-2 variants of concern (VOCs) emerged during the COVID-19 pandemic. Here, we used unbiased systems approaches to study the host-selective forces driving VOC evolution. We discovered that VOCs evolved convergent strategies to remodel the host by modulating viral RNA and protein levels, altering viral and host protein phosphorylation, and rewiring virus-host protein-protein interactions. Integrative computational analyses revealed that although Alpha, Beta, Gamma, and Delta ultimately converged to suppress interferon-stimulated genes (ISGs), Omicron BA.1 did not. ISG suppression correlated with the expression of viral innate immune antagonist proteins, including Orf6, N, and Orf9b, which we mapped to specific mutations. Later Omicron subvariants BA.4 and BA.5 more potently suppressed innate immunity than early subvariant BA.1, which correlated with Orf6 levels, although muted in BA.4 by a mutation that disrupts the Orf6-nuclear pore interaction. Our findings suggest that SARS-CoV-2 convergent evolution overcame human adaptive and innate immune barriers, laying the groundwork to tackle future pandemics.
Topics: Humans; COVID-19; Immunity, Innate; Pandemics; SARS-CoV-2
PubMed: 37738970
DOI: 10.1016/j.cell.2023.08.026 -
Plitidepsin cellular binding and Rac1/JNK pathway activation depend on membrane cholesterol content.Molecular Pharmacology Nov 2006Plitidepsin (aplidin) is a marine cyclic depsipeptide in phase II clinical development against several neoplasias. Plitidepsin is a potent inducer of apoptosis through...
Plitidepsin (aplidin) is a marine cyclic depsipeptide in phase II clinical development against several neoplasias. Plitidepsin is a potent inducer of apoptosis through the sustained activation of Jun N-terminal kinase (JNK). We have reported that this activation depends on the early induction of oxidative stress, activation of Rac1 small GTPase, and the later down-regulation of MKP-1 phosphatase. Using Scatchard and saturation binding analyses, we have found that (14)C-labeled plitidepsin binds to a moderately high-affinity receptor (K(d) of 44.8 +/- 3.1 and 35.5 +/- 4.8 nM, respectively) in MDA-MB-231 breast cancer cells. Two minutes after addition to cells, half of the drug was membrane-bound and was subsequently found in the cytosolic fraction. At 4 degrees C, plitidepsin cellular binding was around 10-fold lower than at 37 degrees C but sufficed to induce cell death, suggesting that this process is triggered from the membrane. Depletion of plasma membrane cholesterol by short treatment with methyl-beta-cyclodextrin diminished plitidepsin binding and Rac1 and JNK activation. Rac1 is targeted to the plasma membrane by plitidepsin as shown by subcellular fractioning and immunofluorescence analysis followed by confocal microscopy. Methyl-beta-cyclodextrin blocked this effect. A subline of HeLa cells (HeLa-R), partially resistant to plitidepsin, showed similar affinity (K(d) of 79.5 +/- 2.5 versus 37.7 +/- 8.2 nM) but 7.5-fold lower binding capacity than wild-type HeLa cells. Moreover, HeLa-R cells had lower total (71%) and membrane (67%) cholesterol content and membrane-bound Rac1, and showed no Rac1 activation upon plitidepsin treatment. In conclusion, cellular plitidepsin uptake and induction of apoptosis via activation of the Rac1-JNK pathway is membrane-cholesterol dependent.
Topics: Cell Membrane; Cholesterol; Depsipeptides; Drug Resistance, Neoplasm; Enzyme Activation; HeLa Cells; Humans; JNK Mitogen-Activated Protein Kinases; Peptides, Cyclic; Protein Transport; Tumor Cells, Cultured; rac1 GTP-Binding Protein
PubMed: 16928956
DOI: 10.1124/mol.106.025569