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1.
Nat Struct Mol Biol ; 31(2): 378-389, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326650

RESUMO

E3 ubiquitin ligases, in collaboration with E2 ubiquitin-conjugating enzymes, modify proteins with poly-ubiquitin chains. Cullin-RING ligase (CRL) E3s use Cdc34/UBE2R-family E2s to build Lys48-linked poly-ubiquitin chains to control an enormous swath of eukaryotic biology. Yet the molecular mechanisms underlying this exceptional linkage specificity and millisecond kinetics of poly-ubiquitylation remain unclear. Here we obtain cryogenic-electron microscopy (cryo-EM) structures that provide pertinent insight into how such poly-ubiquitin chains are forged. The CRL RING domain not only activates the E2-bound ubiquitin but also shapes the conformation of a distinctive UBE2R2 loop, positioning both the ubiquitin to be transferred and the substrate-linked acceptor ubiquitin within the active site. The structures also reveal how the ubiquitin-like protein NEDD8 uniquely activates CRLs during chain formation. NEDD8 releases the RING domain from the CRL, but unlike previous CRL-E2 structures, does not contact UBE2R2. These findings suggest how poly-ubiquitylation may be accomplished by many E2s and E3s.


Assuntos
Proteínas Culina , Enzimas de Conjugação de Ubiquitina , Proteínas Culina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Ubiquitina/metabolismo , Poliubiquitina/metabolismo
2.
Nat Commun ; 15(1): 1308, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38346999
3.
Mol Cell ; 84(7): 1304-1320.e16, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38382526

RESUMO

Cullin-RING ligases (CRLs) ubiquitylate specific substrates selected from other cellular proteins. Substrate discrimination and ubiquitin transferase activity were thought to be strictly separated. Substrates are recognized by substrate receptors, such as Fbox or BCbox proteins. Meanwhile, CRLs employ assorted ubiquitin-carrying enzymes (UCEs, which are a collection of E2 and ARIH-family E3s) specialized for either initial substrate ubiquitylation (priming) or forging poly-ubiquitin chains. We discovered specific human CRL-UCE pairings governing substrate priming. The results reveal pairing of CUL2-based CRLs and UBE2R-family UCEs in cells, essential for efficient PROTAC-induced neo-substrate degradation. Despite UBE2R2's intrinsic programming to catalyze poly-ubiquitylation, CUL2 employs this UCE for geometrically precise PROTAC-dependent ubiquitylation of a neo-substrate and for rapid priming of substrates recruited to diverse receptors. Cryo-EM structures illuminate how CUL2-based CRLs engage UBE2R2 to activate substrate ubiquitylation. Thus, pairing with a specific UCE overcomes E2 catalytic limitations to drive substrate ubiquitylation and targeted protein degradation.


Assuntos
Proteínas Culina , Ubiquitina-Proteína Ligases , Humanos , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Culina/genética , Proteínas Culina/metabolismo , Ubiquitinação , Ubiquitina/metabolismo , Poliubiquitina/metabolismo , Proteínas de Transporte/metabolismo
4.
Mol Cell ; 84(2): 293-308.e14, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38113892

RESUMO

Ubiquitylation is catalyzed by coordinated actions of E3 and E2 enzymes. Molecular principles governing many important E3-E2 partnerships remain unknown, including those for RING-family GID/CTLH E3 ubiquitin ligases and their dedicated E2, Ubc8/UBE2H (yeast/human nomenclature). GID/CTLH-Ubc8/UBE2H-mediated ubiquitylation regulates biological processes ranging from yeast metabolic signaling to human development. Here, cryoelectron microscopy (cryo-EM), biochemistry, and cell biology reveal this exquisitely specific E3-E2 pairing through an unconventional catalytic assembly and auxiliary interactions 70-100 Å away, mediated by E2 multisite phosphorylation. Rather than dynamic polyelectrostatic interactions reported for other ubiquitylation complexes, multiple Ubc8/UBE2H phosphorylation sites within acidic CK2-targeted sequences specifically anchor the E2 C termini to E3 basic patches. Positions of phospho-dependent interactions relative to the catalytic domains correlate across evolution. Overall, our data show that phosphorylation-dependent multivalency establishes a specific E3-E2 partnership, is antagonistic with dephosphorylation, rigidifies the catalytic centers within a flexing GID E3-substrate assembly, and facilitates substrate collision with ubiquitylation active sites.


Assuntos
Saccharomyces cerevisiae , Enzimas de Conjugação de Ubiquitina , Humanos , Enzimas de Conjugação de Ubiquitina/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fosforilação , Microscopia Crioeletrônica , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
5.
Biochem J ; 480(22): 1817-1831, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37870100

RESUMO

Protein ubiquitylation typically involves isopeptide bond formation between the C-terminus of ubiquitin to the side-chain amino group on Lys residues. However, several ubiquitin ligases (E3s) have recently been identified that ubiquitylate proteins on non-Lys residues. For instance, HOIL-1 belongs to the RING-in-between RING (RBR) class of E3s and has an established role in Ser ubiquitylation. Given the homology between HOIL-1 and ARIH1, an RBR E3 that functions with the large superfamily of cullin-RING E3 ligases (CRLs), a biochemical investigation was undertaken, showing ARIH1 catalyzes Ser ubiquitylation to CRL-bound substrates. However, the efficiency of ubiquitylation was exquisitely dependent on the location and chemical environment of the Ser residue within the primary structure of the substrate. Comprehensive mutagenesis of the ARIH1 Rcat domain identified residues whose mutation severely impacted both oxyester and isopeptide bond formation at the preferred site for Ser ubiquitylation while only modestly affecting Lys ubiquitylation at the physiological site. The results reveal dual isopeptide and oxyester protein ubiquitylation activities of ARIH1 and set the stage for physiological investigations into this function of emerging importance.


Assuntos
Ubiquitina-Proteína Ligases , Ubiquitina , Ubiquitina/genética , Ubiquitina/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/metabolismo , Proteínas/metabolismo , Catálise
6.
Nat Commun ; 14(1): 6001, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37752125

RESUMO

The recent proliferation of NISQ devices has made it imperative to understand their power. In this work, we define and study the complexity class NISQ, which encapsulates problems that can be efficiently solved by a classical computer with access to noisy quantum circuits. We establish super-polynomial separations in the complexity among classical computation, NISQ, and fault-tolerant quantum computation to solve some problems based on modifications of Simon's problems. We then consider the power of NISQ for three well-studied problems. For unstructured search, we prove that NISQ cannot achieve a Grover-like quadratic speedup over classical computers. For the Bernstein-Vazirani problem, we show that NISQ only needs a number of queries logarithmic in what is required for classical computers. Finally, for a quantum state learning problem, we prove that NISQ is exponentially weaker than classical computers with access to noiseless constant-depth quantum circuits.

7.
J Hematol Oncol Pharm ; 13(1): 19-25, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36998525

RESUMO

BACKGROUND: The diversity in the genomic landscape of advanced and metastatic tumors calls for combination therapies based on the genomic signature associated with each tumor. Determining safe and tolerable doses for novel combinations of oncology drugs is essential for a precision medicine approach, but can also require dose reductions. Trametinib, palbociclib, and everolimus are among the targeted therapies most often used in novel combinations at our precision medicine clinic. OBJECTIVE: To evaluate the safe, tolerable dosing of trametinib, palbociclib, and everolimus when used as part of novel combinations with other agents for the treatment of advanced or metastatic solid tumors. METHODS: This retrospective study included adult patients with advanced or metastatic solid tumors who received trametinib, everolimus, or palbociclib plus other therapies as a part of novel combinations between December 2011 and July 2018 at the University of California San Diego. Patients were excluded if they received trametinib, everolimus, or palbociclib in standard combinations, such as dabrafenib plus trametinib, everolimus plus fulvestrant, everolimus plus letrozole, and palbociclib plus letrozole. Dosing and adverse events were determined through a review of the electronic medical records. A safe, tolerable drug combination dose was defined as being tolerated for at least 1 month, with no clinically significant serious adverse events. RESULTS: A safe, tolerable dose was determined for 76% of the 71 patients who received trametinib, 88% of the 48 patients who received everolimus, and 73% of the 41 patients receiving palbociclib when used in combination with other therapies. For patients with clinically significant adverse events, dose reductions were attempted in 30% of the trametinib recipients, in 17% of everolimus recipients, and in 45% of palbociclib recipients. When used in combination with other therapies, the optimal dosing of trametinib, palbociclib, and everolimus was lower than the standard single-agent dosing: it was 1 mg daily for trametinib; 5 mg daily for everolimus; and 75 mg daily, for 3 weeks on and 1 week off for palbociclib. Of note, everolimus could not be given concomitantly with trametinib at these doses. CONCLUSION: Safe and tolerable dosing of novel combination therapies that includes trametinib, everolimus, or palbociclib is feasible for a precision medicine approach. However, neither results from this study nor results from previous studies could support the use of everolimus in combination with trametinib, even at reduced doses.

8.
Mol Cell ; 83(5): 770-786.e9, 2023 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-36805027

RESUMO

E3 ligase recruitment of proteins containing terminal destabilizing motifs (degrons) is emerging as a major form of regulation. How those E3s discriminate bona fide substrates from other proteins with terminal degron-like sequences remains unclear. Here, we report that human KLHDC2, a CRL2 substrate receptor targeting C-terminal Gly-Gly degrons, is regulated through interconversion between two assemblies. In the self-inactivated homotetramer, KLHDC2's C-terminal Gly-Ser motif mimics a degron and engages the substrate-binding domain of another protomer. True substrates capture the monomeric CRL2KLHDC2, driving E3 activation by neddylation and subsequent substrate ubiquitylation. Non-substrates such as NEDD8 bind KLHDC2 with high affinity, but its slow on rate prevents productive association with CRL2KLHDC2. Without substrate, neddylated CRL2KLHDC2 assemblies are deactivated via distinct mechanisms: the monomer by deneddylation and the tetramer by auto-ubiquitylation. Thus, substrate specificity is amplified by KLHDC2 self-assembly acting like a molecular timer, where only bona fide substrates may bind before E3 ligase inactivation.


Assuntos
Proteínas , Ubiquitina-Proteína Ligases , Humanos , Proteínas de Transporte , Proteínas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
9.
Science ; 376(6598): 1182-1186, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679419

RESUMO

Quantum technology promises to revolutionize how we learn about the physical world. An experiment that processes quantum data with a quantum computer could have substantial advantages over conventional experiments in which quantum states are measured and outcomes are processed with a classical computer. We proved that quantum machines could learn from exponentially fewer experiments than the number required by conventional experiments. This exponential advantage is shown for predicting properties of physical systems, performing quantum principal component analysis, and learning about physical dynamics. Furthermore, the quantum resources needed for achieving an exponential advantage are quite modest in some cases. Conducting experiments with 40 superconducting qubits and 1300 quantum gates, we demonstrated that a substantial quantum advantage is possible with today's quantum processors.

10.
Cardiovasc Intervent Radiol ; 45(4): 405-412, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35119481

RESUMO

PURPOSE: Transarterial chemoembolization (TACE) is the standard of care for patients with intermediate-stage hepatocellular carcinoma (HCC). Lenvatinib, a multikinase inhibitor, and pembrolizumab, a PD-1 inhibitor, have shown efficacy and tolerability in patients with HCC, and adding this combination to TACE may enhance clinical benefit. PROTOCOL: LEAP-012 is a prospective, double-blind randomized phase 3 study. Adults with confirmed HCC localized to the liver without portal vein thrombosis and not amenable to curative treatment, ≥ 1 measurable tumor per Response Evaluation Criteria in Solid Tumors 1.1 (RECIST 1.1), Eastern Cooperative Oncology Group performance status 0 or 1, Child-Pugh class A and no previous systemic treatment for HCC are eligible. Patients will be randomly assigned to lenvatinib once daily plus pembrolizumab every 6 weeks plus TACE or placebos plus TACE. Dual primary endpoints are overall survival and progression-free survival per RECIST 1.1 by blinded independent central review (BICR). Secondary endpoints are progression-free survival, objective response rate, disease control rate, duration of response and time to progression per modified RECIST by BICR; objective response rate, disease control rate, duration of response and time to progression per RECIST 1.1 by BICR; and safety. STATISTICS: The planned sample size, 950 patients, was calculated to permit accumulation of sufficient overall survival events in 5 years to achieve 90% power for the overall survival primary endpoint. DISCUSSION: LEAP-012 will evaluate the clinical benefit of adding lenvatinib plus pembrolizumab to TACE in patients with intermediate-stage HCC not amenable to curative treatment. CLINICALTRIALS: gov NCT04246177.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Adulto , Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/efeitos adversos , Humanos , Neoplasias Hepáticas/patologia , Compostos de Fenilureia , Estudos Prospectivos , Quinolinas , Resultado do Tratamento
11.
Pulm Ther ; 7(2): 471-486, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34152585

RESUMO

INTRODUCTION: Chronic cough is a highly problematic symptom for patients with idiopathic pulmonary fibrosis (IPF); limited therapeutic options are available. We evaluated gefapixant, a P2X3 receptor antagonist, for the treatment of chronic cough in IPF. METHODS: This randomized, double-blind, placebo-controlled, crossover study included subjects with IPF. Sequence A included gefapixant 50 mg BID (period 1; 14 days) followed by placebo (period 2; 14 days); sequence B had the opposite sequence of treatments. This regimen was specified in a protocol amendment that modified the original active treatment regimen of gefapixant 50 mg BID for 10 days and 150 mg BID for 4 days. Patients randomized to the original treatment regimen were excluded from efficacy analyses but included in safety assessments. The primary efficacy endpoint was change from baseline in awake cough frequency (coughs/hour) from periods 1 and 2 combined. Adverse events (AEs) were monitored throughout the study. RESULTS: A total of 51 subjects were randomized, 44 of whom were randomized to treatment sequences evaluated in the primary efficacy analysis (i.e., 22 subjects in sequence A and 22 subjects in sequence B); seven subjects received the treatment assigned before the protocol amendment and were excluded from efficacy analyses. The change from baseline in awake cough frequency from periods 1 and 2 combined (mixed model for repeated measures analysis) did not demonstrate a significant reduction versus placebo in cough at day 14 (p = 0.90); in a post hoc analysis of log-transformed data p value for reduction versus placebo at day 14 was 0.07. The most common AEs were related to taste (dysgeusia and ageusia). CONCLUSIONS: Gefapixant was generally well tolerated but was not associated with a significant improvement in chronic cough in subjects with IPF as defined by the primary endpoint in this study. TRIAL REGISTRATION: NCT02502097.

12.
Oncol Ther ; 9(2): 525-539, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34120312

RESUMO

INTRODUCTION: Dacomitinib and gefitinib are irreversible epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) indicated for the first-line treatment of patients with advanced non-small cell lung cancer (NSCLC) and EGFR-activating mutations. Pharmacokinetic (PK) studies in healthy volunteers suggested that acid-reducing drugs such as proton pump inhibitors (PPI) decreased dacomitinib and gefitinib exposure by limiting the pH-dependent absorption. This analysis retrospectively evaluates the effect of concomitant PPI use on dacomitinib exposure and on progression-free survival (PFS) and overall survival (OS) in patients treated with dacomitinib 45 mg QD or gefitinib 250 mg QD in a 1:1 randomized phase 3 study (ARCHER 1050). METHODS: The analysis grouped all patients (n = 452) treated in each arm of the study as non-PPI users, PPI users, or extensive PPI users. PFS and OS data were presented by Kaplan-Meier plots and analyzed using Cox proportional hazards models. Dacomitinib exposure was compared using a linear mixed-effects model. RESULTS: Results showed that dacomitinib PFS and OS did not differ significantly when comparing PPI users (N = 59) to non-PPI users (N = 152), while extensive PPI users (N = 24) had shorter PFS [hazard ratio (HR): 1.94, p = 0.011] and OS (HR: 1.77, p = 0.027) when compared to non-PPI users. For patients treated with gefitinib, PFS did not differ significantly when comparing PPI users (N = 51) and extensive PPI users (N = 19) to non-PPI users (N = 159); however, both PPI users (HR: 1.65, p = 0.007) and extensive PPI users (HR: 1.70, p = 0.050) had shorter OS when compared to non-PPI users. Further analysis by adjusting potential confounders indicated no statistically significant differences in PFS or OS between any PPI user vs. non-PPI user groups in the dacomitinib and gefitinib arms. PPI use did not appear to affect dacomitinib exposure. CONCLUSION: In conclusion, PPI use in patients with NSCLC likely has minimal impact on dacomitinib or gefitinib efficacy despite decreased absorption of these drugs observed in PK studies. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT01774721.

13.
Clin Pharmacokinet ; 60(10): 1303-1312, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33937953

RESUMO

BACKGROUND AND OBJECTIVE: Lorlatinib is a third-generation tyrosine kinase inhibitor approved for the second-line treatment of patients with advanced anaplastic lymphoma kinase-positive non-small cell lung cancer. Lorlatinib is metabolized by cytochrome P450 (CYP) 3A and contraindicated with strong CYP3A inducers because of significant transaminase elevation. This phase I, open-label, two-period study evaluated the impact of a moderate CYP3A inducer, modafinil, on the safety and pharmacokinetics of lorlatinib. METHODS: Healthy participants received single-dose oral lorlatinib (50 mg [n = 2], 75 mg [n = 2], or 100 mg [n = 2 + 10 in an expanded cohort]) in Period 1 followed by modafinil 400 mg/day (days 1-19) and single-dose lorlatinib (day 15, same dose as previous) both orally in Period 2. Blood samples were collected for 120 h after each dose of lorlatinib. RESULTS: Of 16 participants, ten completed the study; six participants, all in the expanded 100-mg cohort, discontinued because of adverse events during the modafinil lead-in dosing period. Single doses of lorlatinib 50-100 mg were well tolerated when administered alone and in the presence of steady-state modafinil. Of the ten participants who completed the study, all had transaminase values within normal limits during the combination of lorlatinib with modafinil. The ratios of the adjusted geometric means (90% confidence interval) for lorlatinib area under the plasma concentration-time profile extrapolated to infinity and maximum plasma concentration were 76.69% (70.15-83.83%) and 77.78% (65.92-91.77), respectively, when lorlatinib 100 mg was co-administered with steady-state modafinil compared with lorlatinib administration alone. CONCLUSION: Lorlatinib 100 mg may be safely co-administered with moderate CYP3A inducers. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT03961997; registered 23 May, 2019.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Aminopiridinas , Área Sob a Curva , Interações Medicamentosas , Voluntários Saudáveis , Humanos , Lactamas , Modafinila , Pirazóis
14.
Mol Pain ; 17: 17448069211000910, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33719729

RESUMO

Common approaches to studying mechanisms of chronic pain and sensory changes in pre-clinical animal models involve measurement of acute, reflexive withdrawal responses evoked by noxious stimuli. These methods typically do not capture more subtle changes in sensory processing nor report on the consequent behavioral changes. In addition, data collection and analysis protocols are often labour-intensive and require direct investigator interactions, potentially introducing bias. In this study, we develop and characterize a low-cost, easily assembled behavioral assay that yields self-reported temperature preference from mice that is responsive to peripheral sensitization. This system uses a partially automated and freely available analysis pipeline to streamline the data collection process and enable objective analysis. We found that after intraplantar administration of the TrpV1 agonist, capsaicin, mice preferred to stay in cooler temperatures than saline injected mice. We further observed that gabapentin, a non-opioid analgesic commonly prescribed to treat chronic pain, reversed this aversion to higher temperatures. In contrast, optogenetic activation of the central terminals of TrpV1+ primary afferents via in vivo spinal light delivery did not induce a similar change in thermal preference, indicating a possible role for peripheral nociceptor activity in the modulation of temperature preference. We conclude that this easily produced and robust sensory assay provides an alternative approach to investigate the contribution of central and peripheral mechanisms of sensory processing that does not rely on reflexive responses evoked by noxious stimuli.


Assuntos
Capsaicina/farmacologia , Temperatura Alta , Nociceptores/efeitos dos fármacos , Dor/tratamento farmacológico , Reflexo/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Camundongos , Nociceptores/metabolismo , Optogenética/métodos , Dor/fisiopatologia , Estimulação Física/métodos , Reflexo/fisiologia , Canais de Cátion TRPV/genética
15.
Clin Pharmacol Drug Dev ; 10(7): 707-717, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33356019

RESUMO

This phase I open-label trial (NCT03627754) assessed glasdegib pharmacokinetics and safety in otherwise healthy participants with moderate (Child-Pugh B) or severe (Child-Pugh C) hepatic impairment. Participants with hepatic impairment and age/weight-matched controls with normal hepatic function received a single oral 100-mg glasdegib dose under fasted conditions. The primary end points were area under the plasma concentration-time curve from time zero to infinity (AUCinf ) and maximum plasma concentration (Cmax ). Twenty-four participants (8/cohort) were enrolled. Glasdegib plasma exposures in moderate hepatic impairment were similar to controls, with adjusted geometric mean ratios (GMRs) of 110.8% (90% confidence interval [CI], 78.0-157.3) for AUCinf and 94.8% (69.9-128.4) for Cmax versus controls. In severe hepatic impairment, glasdegib plasma exposures were lower than controls (AUCinf GMR, 75.7%; 90%CI, 51.5-111.0; Cmax GMR, 58.0%; 90%CI, 37.8-89.0). Unbound glasdegib exposures were similar to controls for moderate (AUCinf,u GMR, 118.1%; 90%CI, 88.7-157.2; Cmax,u GMR, 101.1%; 90%CI, 78.4-130.3) and severe hepatic impairment (AUCinf,u GMR, 116.3%; 90%CI 81.8-165.5; Cmax,u GMR, 89.2%, 90%CI, 60.2-132.3). No treatment-related adverse events or clinically significant changes in laboratory values, vital signs, or electrocardiograms were observed. Together with previous findings, this suggests glasdegib dose modifications are not required based on hepatic impairment.


Assuntos
Antineoplásicos/farmacocinética , Benzimidazóis/farmacocinética , Hepatopatias/fisiopatologia , Compostos de Fenilureia/farmacocinética , Idoso , Antineoplásicos/efeitos adversos , Área Sob a Curva , Benzimidazóis/efeitos adversos , Estudos de Casos e Controles , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Índice de Gravidade de Doença
16.
Clin Pharmacol Ther ; 109(1): 184-192, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32866318

RESUMO

VRC01 is a first-in-class, potent, broadly neutralizing antibody that targets the CD4 binding site of gp120 on HIV-1 viruses, and is under development as a novel HIV therapeutic. This study utilized population pharmacokinetic (PK) modeling to characterize VRC01 PK to guide dosing selection for ongoing phase II clinical trials in pediatric patients. Combining VRC01 PK data from 3 adult and 1 infant clinical trials, a total of 1,475 VRC01 serum concentrations from 100 participants were used in the analysis (40 infants and 60 adults). VRC01 was administered either i.v. or s.c. (1-40 mg/kg). All infants received s.c. doses as compared with 13% s.c. and 87% i.v. in adults. The data were well-described by a two-compartment model. Clearance was 37% higher in adults with HIV infection and 83% lower in infants than adults. Subcutaneous bioavailability was 55% in adults. Rapid absorption was seen in infants indicating therapeutic levels could be achieved quickly. Monte Carlo simulations were used to determine optimal dosing and demonstrated 40 mg/kg s.c. at weeks 0, 2, 6, and 10 would maintain VRC01 levels at the suppressive target concentration of 50 µg/mL for the first 14 weeks of life in infants. The current analysis provides new insight into differences in monoclonal antibody PK between infants and adults and demonstrates the utility of a population PK approach in informing drug development for infant populations.


Assuntos
Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/uso terapêutico , Anticorpos Amplamente Neutralizantes/farmacologia , Anticorpos Amplamente Neutralizantes/uso terapêutico , Anticorpos Anti-HIV/uso terapêutico , Adulto , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Pain ; 162(5): 1416-1425, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33230005

RESUMO

ABSTRACT: The development of new analgesic drugs has been hampered by the inability to translate preclinical findings to humans. This failure is due in part to the weak connection between commonly used pain outcome measures in rodents and the clinical symptoms of chronic pain. Most rodent studies rely on the use of experimenter-evoked measures of pain and assess behavior under ethologically unnatural conditions, which limits the translational potential of preclinical research. Here, we addressed this problem by conducting an unbiased, prospective study of behavioral changes in mice within a natural homecage environment using conventional preclinical pain assays. Unexpectedly, we observed that cage-lid hanging, a species-specific elective behavior, was the only homecage behavior reliably impacted by pain assays. Noxious stimuli reduced hanging behavior in an intensity-dependent manner, and the reduction in hanging could be restored by analgesics. Finally, we developed an automated approach to assess hanging behavior. Collectively, our results indicate that the depression of hanging behavior is a novel, ethologically valid, and translationally relevant pain outcome measure in mice that could facilitate the study of pain and analgesic development.


Assuntos
Comportamento Animal , Dor , Analgésicos/uso terapêutico , Animais , Camundongos , Dor/tratamento farmacológico , Medição da Dor , Estudos Prospectivos
18.
Pharmaceutics ; 12(4)2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32272733

RESUMO

INTRODUCTION: Dacomitinib is an epidermal growth factor receptor (EGFR) inhibitor approved for the treatment of metastatic non-small cell lung cancer (NSCLC) in the first line in patients with EGFR activating mutations. Dacomitinib is taken orally once daily at 45 mg with or without food, until disease progression or unacceptable toxicity occurs. Oncology patients often can develop gastroesophageal reflux disease (GERD), which may require management with an acid-reducing agent. Proton pump inhibitors (PPIs), such as rabeprazole, inhibit sodium-potassium adenosine triphosphatase (H+/K+-ATPase) pumps that stimulate acid secretion in the stomach and have a prolonged pharmacodynamic effect that extends beyond 24 h post-administration. The aim of this work was to characterize the absorption of dacomitinib via modeling with a particular interest in quantifying the impact of rabeprazole on the pharmacokinetics (PK) of dacomitinib. MATERIALS AND METHODS: The pooled dataset consisted of five clinical pharmacology healthy volunteer studies, which collected serial pharmacokinetic concentration-time profiles of dacomitinib. Non-linear mixed effects modeling was carried out to characterize dacomitinib pharmacokinetics in the presence and absence of the concomitant use of a PPI, rabeprazole. Several absorption models, some more empirical, and some more physiologically based, were tested: transit compartment, first-order absorption with and without lag time, and variations of combined zero- and first-order absorption kinetics models. RESULTS: The presence of a PPI was a significant covariate affecting the extent (F) and rate (ka) of dacomitinib absorption, as previously reported in the dedicated clinical study. A transit compartment model was able to best describe the absorption phase of dacomitinib.

19.
Phys Chem Chem Phys ; 22(6): 3748, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32022090

RESUMO

Correction for 'Understanding of binding energy calibration in XPS of lanthanum oxide by in situ treatment' by Jerry Pui Ho Li et al., Phys. Chem. Chem. Phys., 2019, 21, 22351-22358.

20.
J Med Chem ; 63(2): 470-489, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31549836

RESUMO

Zika virus is an emerging flavivirus that causes the neurodevelopmental congenital Zika syndrome and that has been linked to the neuroinflammatory Guillain-Barré syndrome. The absence of a vaccine or a clinically approved drug to treat the disease combined with the likelihood that another outbreak will occur in the future defines an unmet medical need. Several promising drug candidate molecules have been reported via repurposing studies, high-throughput compound library screening, and de novo design in the short span of a few years. Intense research activity in this area has occurred in response to the World Health Organization declaration of a Public Health Emergency of International Concern on February 1, 2016. In this Perspective, the authors review the emergence of Zika virus, the biology of its replication, targets for therapeutic intervention, target product profile, and current drug development initiatives.


Assuntos
Antivirais/uso terapêutico , Infecção por Zika virus/tratamento farmacológico , Zika virus/efeitos dos fármacos , Animais , Desenvolvimento de Medicamentos , Descoberta de Drogas , Humanos , Vacinas Virais , Infecção por Zika virus/patologia , Infecção por Zika virus/prevenção & controle
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