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CRS3123 is a novel small molecule that potently inhibits methionyl-tRNA synthetase of Clostridioides difficile, inhibiting C. difficile toxin production and spore formation. CRS3123 has been evaluated in a multiple-ascending-dose placebo-controlled phase 1 trial. Thirty healthy subjects, ages 18 to 45 years, were randomized into three cohorts of 10 subjects each, receiving either 200, 400, or 600 mg of CRS3123 (8 subjects per cohort) or placebo (2 subjects per cohort) by oral administration twice daily for 10 days. CRS3123 was generally safe and well tolerated, with no serious adverse events (SAEs) or severe treatment-emergent adverse events (TEAEs) reported. All subjects completed their assigned treatment and follow-up visits, and there were no trends in systemic, vital sign, or laboratory TEAEs. There were no QTcF interval changes or any clinically significant changes in other electrocardiogram (ECG) intervals or morphology. CRS3123 showed limited but detectable systemic uptake; although absorption increased with increasing dose, the increase was less than dose proportional. Importantly, the bulk of the oral dose was not absorbed, and fecal concentrations were substantially above the MIC90 value of 1 µg/ml at all dosages tested. Subjects receiving either of the two lower doses of CRS3123 exhibited minimal disruption of normal gut microbiota after 10 days of twice-daily dosing. CRS3123 was inactive against important commensal anaerobes, including Bacteroides, bifidobacteria, and commensal clostridia. Microbiome data showed favorable differentiation compared to other CDI therapeutics. These results support further development of CRS3123 as an oral agent for the treatment of CDI. (This study has been registered at Clinicaltrials.gov under identifier NCT02106338.).
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Antibacterianos/administração & dosagem , Benzopiranos/administração & dosagem , Clostridioides difficile/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Tiofenos/administração & dosagem , Administração Oral , Adolescente , Adulto , Antibacterianos/efeitos adversos , Antibacterianos/farmacocinética , Benzopiranos/efeitos adversos , Benzopiranos/farmacocinética , Clostridioides difficile/enzimologia , Clostridioides difficile/genética , Infecções por Clostridium/tratamento farmacológico , Estudos de Coortes , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Eletrocardiografia , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Feminino , Voluntários Saudáveis , Humanos , Masculino , Metionina tRNA Ligase/antagonistas & inibidores , Metionina tRNA Ligase/genética , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tiofenos/efeitos adversos , Tiofenos/farmacocinética , Adulto JovemRESUMO
Clostridium difficile causes antibiotic-associated diarrhea and is a major public health concern. Current therapies disrupt the protective intestinal flora, do not reliably prevent recurrent infections, and will be decreasingly effective should less susceptible strains emerge. CRS3123 is an oral agent that inhibits bacterial methionyl-tRNA synthetase and has potent activity against C. difficile and aerobic Gram-positive bacteria but little activity against Gram-negative bacteria, including anaerobes. This first-in-human, double-blind, placebo-controlled, dose escalation study evaluated the safety and systemic exposure of CRS3123 after a single oral dose in healthy adults. Five cohorts of eight subjects each received CRS3123 or placebo in a 3:1 ratio. Doses for the respective active arms were 100 mg, 200 mg, 400 mg, 800 mg, and 1,200 mg. Blood and urine were collected for pharmacokinetic analysis. CRS3123 concentrations were measured with validated LC-MS/MS techniques. There were no serious adverse events or immediate allergic reactions during administration of CRS3123. In the CRS3123-treated groups, the most frequent adverse events were decreased hemoglobin, headache, and abnormal urine analysis; all adverse events in the active-treatment groups were mild to moderate, and their frequency did not increase with dose. Although CRS3123 systemic exposure increased at higher doses, the increase was less than dose proportional. The absorbed drug was glucuronidated at reactive amino groups on the molecule, which precluded accurate pharmacokinetic analysis of the parent drug. Overall, CRS3123 was well tolerated over this wide range of doses. This safety profile supports further investigation of CRS3123 as a treatment for C. difficile infections. (This study has been registered at ClinicalTrials.gov under identifier NCT01551004.).
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Antibacterianos/farmacocinética , Antibacterianos/uso terapêutico , Benzopiranos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Infecções por Clostridium/tratamento farmacológico , Metionina tRNA Ligase/antagonistas & inibidores , Tiofenos/farmacologia , Adulto , Benzopiranos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/prevenção & controle , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Placebos/uso terapêutico , Tiofenos/uso terapêutico , Adulto JovemRESUMO
The National Psoriasis Foundation surveyed a random, stratified sample of individuals with psoriatic disease in the United States to determine the prevalence of an unacceptable psoriatic arthritis (PsA) symptom state and its effect on depression and social participation. Acceptable and unacceptable levels of PsA were defined using established cutoff points (acceptable ≤4 vs unacceptable >4) on the Psoriatic Arthritis Impact of Disease 9. Psoriasis severity was defined by body surface area: mild < 3%, moderate-severe ≥ 3%. Depression was assessed utilizing the Patient Health Questionnaire 2. Social participation was assessed by the Patient Reported Outcome Information Measurement System Ability to Participate in Social Role and Activities-SF4a. The analysis cohort comprised 801 patients with PsA. Unacceptable disease activity level (Psoriatic Arthritis Impact of Disease >4) was reported by 59.6% of participants. After adjusting for age, sex, and psoriasis severity, individuals with likely depression (OR = 0.014, P < .001) and those with limited ability to participate in social roles and activities (OR = 0.05, P < .001) were less likely to experience acceptable levels of PsA activity. Ultimately, the results demonstrated that most United States patients with PsA have unacceptable levels of disease activity, which is associated with increased prevalence of depression and limitations in social participation.
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INTRODUCTION: Achievement of remission in psoriatic arthritis is a key goal for patients and clinicians, yet definitions of remission may vary. Previous efforts have utilized multidomain measures such as minimal disease activity that assess the status of joints, skin, and function to determine current level of psoriatic arthritis (PsA) disease activity. The goal of this study is to identify factors associated with patient-reported psoriatic arthritis remission. METHODS: The National Psoriasis Foundation conducted a cross-sectional study using an online survey of a random stratified sample of 1570 individuals with psoriatic disease in the USA. Participants were asked about a provider diagnosis of psoriasis and/or psoriatic arthritis, comorbid conditions, and psoriatic arthritis impact and disease activity, and demographic questions. All participants reporting a physician-given diagnosis of psoriatic arthritis were asked if they felt their psoriatic arthritis was in remission ("Do you feel your psoriatic arthritis is in remission?" Yes/No/Unsure) and, if so, length of remission. Individuals with psoriasis and psoriatic arthritis reporting a body surface area impacted by psoriasis 3% or less were asked if they felt their psoriasis was in remission. Psoriatic arthritis disease activity and impact was assessed using the nine-question Psoriatic Arthritis Impact of Disease (PsAID-9) instrument and a global PsA-related quality of life question. PsAID-9 scores ≤ 4 were used to indicate acceptable disease state. Multivariate logistic regression was used to identify factors associated with patient-perceived PsA remission. RESULTS: Of 834 participants with PsA, including 76 (4.8%) with PsA without skin involvement ever, 144 (17.3%) felt their psoriatic arthritis was in remission, with an average remission duration of 43 months. Of those in remission, 116 (78.4%) reported currently using a treatment for their PsA, with most (75.7%) reporting using a biologic therapy for their PsA in the past 12 months. Multivariate logistic regression revealed that patient-perceived psoriatic arthritis remission was independently associated with experiencing acceptable disease state (PsAID-9 ≤ 4), perception of psoriasis remission, lower impact of PsA on global quality of life, and non-white race. Age, sex, body mass index, or biologic use in the last 12 months were not associated with patient-reported PsA remission. CONCLUSION: Overall, patient perception of PsA remission was most strongly associated with patient-reported psoriasis remission.
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INTRODUCTION: Achievement of remission in psoriasis is a key goal for patients and providers, yet definitions of remission may vary. Some treat-to-target initiatives in psoriasis have focused on degree of skin involvement, while others have also incorporated quality of life (QoL) measures. The goal of this study is to identify factors associated with patient-reported psoriasis remission. METHODS: The National Psoriasis Foundation conducted a survey of a random stratified sample of 1570 individuals with psoriatic disease in the USA. The survey contained questions regarding provider diagnosis of psoriasis and/or psoriatic arthritis, as well as comorbid conditions and participant demographics. Psoriasis severity was assessed using the Patient Report of Extent of Psoriasis Involvement (PREPI), a validated self-reported measure of body surface area (BSA). Dermatologic-related quality of life was assessed using the Dermatology Life Quality Index (DLQI). Individuals reporting BSA ≤ 3% were asked if they believed their psoriasis was in remission. Multivariate logistic regression was used to identify factors associated with remission. RESULTS: Of 930 participants reporting BSA ≤ 3%, 479 (51.7%) believed their psoriasis was in remission, with an average remission duration of 31 months. Of those in remission, 79.1% reported current treatment. Multivariate regression revealed that psoriasis remission was independently associated with female sex, lower BSA, less impairment in the Dermatology Life Quality Index and global QoL, biologic use, and concomitant diagnosis of psoriatic arthritis. There was no association with age, race, body mass index, or number of comorbidities. CONCLUSION: Overall, patient perception of psoriasis remission was not solely associated with BSA, but also with sex, quality of life, and treatment type.
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IMPORTANCE: Determining psoriasis prevalence is fundamental to understanding the burden of the disease, the populations most affected, and health policies to address the disease. OBJECTIVE: (1) To determine the prevalence of psoriasis among adults in the US and (2) to evaluate the change in psoriasis prevalence over time since the 2003-2004 National Health and Nutrition Examination Survey (NHANES) data. DESIGN, SETTING, AND PARTICIPANTS: This population-based cross-sectional study used 2011-2014 NHANES data (collected from January 1, 2011, to December 31, 2014) with sampling from a general, noninstitutionalized US civilian population. Participants were 20 years or older and were selected via a multistage probability sampling design to ensure that surveys were nationally representative. Eligible participants had an in-person interview followed by a medical examination by medical professionals. Data were analyzed from July 15, 2019, to December 23, 2020. EXPOSURES: None. MAIN OUTCOMES AND MEASURES: Psoriasis prevalence in the US, as measured by the percentage of people in the representative sample with psoriasis, and trend statistics comparing prevalence estimates from the 2003-2004, 2009-2010, and 2011-2014 NHANES cycles. RESULTS: A total of 12â¯625 participants (mean [SD] age, 32.8 [24.1] years; 6492 women [51.4%]; and 4828 non-Hispanic White participants [38.2%]) answered the question of whether they were given the diagnosis of psoriasis by a physician or another health care professional. Psoriasis prevalence among US adults 20 years or older was 3.0% (95% CI, 2.6%-3.4%). Based on the 2020 US census data, this outcome translates to an estimated 7.55 million US adults with psoriasis. Psoriasis prevalence was similar between women and men, with 3.2% (95% CI, 2.6%-3.8%) in women and 2.8% (95% CI, 2.4%-3.3%) in men. Psoriasis prevalence was highest in White individuals at 3.6% (95% CI, 2.9%-4.2%), followed by other racial/ethnic groups (non-Hispanic, including multiracial) at 3.1% (95% CI, 1.2%-5.1%), Asian individuals at 2.5% (95% CI, 1.6%-3.3%), Hispanic individuals (including Mexican American and other Hispanic individuals) at 1.9% (95% CI, 1.3%-2.5%), and Black individuals at 1.5% (95% CI, 1.0%-2.0%). Psoriasis prevalence was not different based on patients' marital status, education, income, or medical insurance status. The prevalence of psoriasis among US adults did not differ significantly since 2003. CONCLUSIONS AND RELEVANCE: The results of this cross-sectional study suggest that psoriasis remains a common, immune-mediated disease that affects 3.0% of the US adult population, or more than 7.5 million adults. Its prevalence has not differed since evaluation in 2003. These prevalence data are foundational to determining the burden of psoriasis and for supporting efforts in research, education, and health policy.
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Hispânico ou Latino , Psoríase , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Inquéritos Nutricionais , Prevalência , Psoríase/epidemiologia , Estados Unidos/epidemiologiaRESUMO
OBJECTIVES: REP3123 is a fully synthetic methionyl-tRNA synthetase inhibitor in pre-clinical development as a novel agent to treat Clostridium difficile infection (CDI). This novel agent was investigated for its ability to block the production of toxins and spores, and was tested for efficacy in vivo in a hamster model. METHODS: Clostridial toxin levels were determined qualitatively using monoclonal antibodies and by cytotoxicity assays. Spores were detected by staining and by quantitative dilution plating after ethanol treatment. Efficacy of REP3123 was tested in a clindamycin-induced C. difficile hamster gastrointestinal (GI) infection model. RESULTS: REP3123 at concentrations as low as 1 mg/L inhibited de novo toxin production in high cell density, stationary phase cultures of C. difficile. Among comparator agents currently used for CDI therapy, vancomycin required much higher levels of 20 mg/L, and metronidazole had no effect on toxin levels. REP3123 caused a >10-fold reduction of the sporulation rate in vitro. Vancomycin and, in particular, metronidazole appeared to promote the formation of spores. REP3123, at concentrations as low as 0.5 mg/kg, demonstrated efficacy in the hamster model of CDI and was superior to vancomycin in the overall survival of the animals at the end of the study (33 days). CONCLUSIONS: REP3123 inhibited growth of C. difficile, affected the production of toxins and spores and demonstrated superior efficacy compared with vancomycin in the hamster GI infection model. This agent may be a promising candidate for CDI treatment; in particular, the inhibition of toxin production and spore formation may reduce the severity and spread of the disease, respectively.
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Antibacterianos/uso terapêutico , Toxinas Bacterianas/biossíntese , Benzopiranos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Enterocolite Pseudomembranosa/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Esporos Bacterianos/efeitos dos fármacos , Tiofenos/farmacologia , Animais , Antibacterianos/farmacologia , Linhagem Celular , Cricetinae , Inibidores Enzimáticos/farmacologia , Masculino , Análise de Sobrevida , Vancomicina/farmacologia , Vancomicina/uso terapêuticoRESUMO
The purpose of this study was to evaluate the potential irritating effects and the systemic exposure level of an antibacterial ointment containing REP8839 as a single agent or in combination with mupirocin versus Bactroban Nasal in rabbits. Additionally, the reversibility of REP8839 effects during a 14-day recovery period was assessed. Five treatment groups of six male and six female New Zealand White rabbits received dose levels of 1%, 2%, and 4% REP8839, 2% Bactroban Nasal, or 2% REP8839/2% mupirocin combination. One additional group of six animals/sex served as the control and received the vehicle, Petrolatum/Softisan 649. The test article or vehicle was administered to all groups via topical administration to the external nares, twice a day (approx. 8h intervals between the doses) for 21 consecutive days, at a dose volume of 100 microL per nare/dose for a total of 400 microL per day (200 microL per nare). Two animals/sex/group were maintained for a 14-day recovery period. The external nares were reflected back and the mucosal lining was evaluated and scored for erythema and edema within 30-60 min following the first dose each day. Blood samples were collected from all animals at designated time points on Day 21 of the study to assess systemic exposure levels. Cross-sectioning of the nasal tract was conducted in all the groups for microscopic evaluation. Mucosal scoring of the nares did not reveal any edema or erythema in any of the dose groups with the antibacterial alone, with the combination product, or with Bactroban Nasal. Mean body weights and food consumption were not adversely impacted by the test articles. Minimal plasma exposure was observed in the rabbits (<5 ng/mL). The REP8839 groups did appear to have dose-responsive exposure (from below the limit of quantitation to 5 ng/mL with 1%, 2%, and 4% REP8839, respectively). Microscopic changes on the nasal sectioning noted in these animals were infrequent and considered incidental findings unrelated to administration of the test articles. In conclusion doses of up to 4% of REP8839 ointment as a single agent or 2% in the combination product, as well as 2% Bactroban Nasal, were not found to induce mucosal irritation when applied topically to the external nares twice a day for 21 consecutive days. Additionally, no delayed effects were observed in the recovery animals.
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Antibacterianos/efeitos adversos , Diaminas/efeitos adversos , Irritantes/efeitos adversos , Mucosa Nasal/efeitos dos fármacos , Tiofenos/efeitos adversos , Administração Intranasal , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Disponibilidade Biológica , Diaminas/administração & dosagem , Diaminas/sangue , Diaminas/farmacocinética , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Edema/induzido quimicamente , Eritema/induzido quimicamente , Feminino , Irritantes/administração & dosagem , Irritantes/farmacocinética , Masculino , Mupirocina/administração & dosagem , Mupirocina/efeitos adversos , Mupirocina/sangue , Mupirocina/farmacocinética , Mucosa Nasal/patologia , Nariz , Pomadas/efeitos adversos , Pomadas/farmacocinética , Coelhos , Tiofenos/administração & dosagem , Tiofenos/sangue , Tiofenos/farmacocinéticaRESUMO
INTRODUCTION: Sleep is essential for overall health and well-being, yet more than one-third of adults report inadequate sleep. The prevalence is higher among people with psoriasis, with up to 85.4% of the psoriatic population reporting sleep disruption. Poor sleep among psoriasis patients is particularly concerning because psoriasis is independently associated with many of the same comorbidities as sleep dysfunction, including cardiovascular disease, obesity, and depression. Given the high prevalence and serious consequences of disordered sleep in psoriasis, it is vital to understand the nature of sleep disturbance in this population. This study was designed to help meet this need by using survey data from Citizen Pscientist, an online patient portal developed by the National Psoriasis Foundation. METHODS: Our analysis included 3118 participants who identified as having a diagnosis by a physician of psoriasis alone or psoriasis with psoriatic arthritis. Demographic information, psoriasis severity and duration, sleep apnea status, smoking and alcohol consumption, itch timing, and sleep characteristics were included. Two separate multivariate logistic regression models in STATA were used to determine whether the presence of psoriatic arthritis, age, gender, body mass index, comorbid sleep apnea, psoriasis severity, timing of worst itch, smoking status, or high-risk alcohol consumption were associated with sleep difficulty or low sleep quantity, defined by the American Academy of Sleep Medicine as less than 7 h of sleep per night on average. RESULTS: Results from the multivariate logistic regressions found that sleep difficulty was associated with psoriatic arthritis (OR 2.15, 95% CI [1.79-2.58]), female gender (2.03 [1.67-2.46]), obese body mass index (BMI ≥ 30) (1.25 [1.00-1.56]), sleep apnea (1.41 [1.07-1.86]), psoriasis severity of moderate (1.59 [1.30-1.94]) or severe (2.40 [1.87-3.08]), and smoking (1.60 [1.26-2.02]). Low sleep quantity was associated with obese BMI (1.62 [1.29-2.03]), sleep apnea (1.30 [1.01-1.68]), psoriasis severity of moderate (1.41 [1.16-1.72]) or severe (1.40 [1.11-1.76]), and smoking (1.62 [1.31-2.00]). Sleep difficulty and low sleep quantity were not associated with age, alcohol consumption, or timing of worst itch. CONCLUSION: These results are potentially meaningful in several aspects. We identify an important distinction between sleep difficulty and sleep quantity in psoriatic disease, whereby having psoriatic arthritis and being female are each associated with sleep difficulty despite no association with low sleep quantity. Furthermore, there is conflicting evidence from prior studies as to whether psoriasis severity is associated with sleep difficulty, but this well-powered, large study revealed a strong, graded relationship between psoriasis severity and both sleep difficulty and low sleep quantity. Overall, our results show that both sleep difficulty and low sleep quantity were associated with multiple factors in this analysis of a large psoriatic cohort. These findings suggest that dermatologists may gather clinically useful information by screening psoriatic patients for trouble sleeping and low sleep quantity to identify potential comorbidities and to more effectively guide disease management.
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Psoríase/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , AutorrelatoRESUMO
BACKGROUND: Pexmetinib (ARRY-614) is a dual inhibitor of p38 mitogen-activated protein kinase and Tie2 signaling pathways implicated in the pathogenesis of myelodysplastic syndromes. Previous clinical experience in a Phase I dose-escalation study of myelodysplastic syndrome patients using pexmetinib administered as neat powder-in-capsule (PIC) exhibited high variability in pharmacokinetics and excessive pill burden, prompting an effort to improve the formulation of pexmetinib. METHODS: A relative bioavailability assessment encompassed three parallel treatment cohorts of unique subjects comparing the two new formulations (12 subjects per cohort), a liquid oral suspension (LOS) and liquid-filled capsule (LFC) and the current clinical PIC formulation (six subjects) in a fasted state. The food-effect assessment was conducted as a crossover of the LOS and LFC formulations administered under fed and fasted conditions. Subjects were divided into two groups of equal size to evaluate potential period effects on the food-effect assessment. RESULTS: The geometric mean values of the total plasma exposures based upon area-under-the-curve to the last quantifiable sample (AUClast) of pexmetinib were approximately four- and twofold higher after administration of the LFC and LOS formulations, respectively, than after the PIC formulation, when the formulations were administered in the fasted state. When the LFC formulation was administered in the fed state, pexmetinib AUClast decreased by <5% compared with the fasted state. After administration of the LOS formulation in the fed state, pexmetinib AUClast was 34% greater than observed in the fasted state. CONCLUSION: These results suggest that the LFC formulation of pexmetinib may achieve greater exposures with lower doses due to the greater bioavailability compared to the PIC, and remain unaffected by coadministration with food.
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Previously we showed that granulocyte colony-stimulating factor (G-CSF) in vitro bioactivity is preserved when the protein is joined via a flexible 7 amino acid linker to an immunoglobulin-1 (IgG1)-Fc domain and that the G-CSF/IgG1-Fc fusion protein possessed a longer circulating half-life and improved hematopoietic properties compared to G-CSF in normal rats. We have extended this analysis by comparing the relative hematopoietic potencies of G-CSF/IgG1-Fc to G-CSF in normal mice and to G-CSF and polyethylene glycol (PEG) -modified G-CSF in neutropenic rats. Mice were treated for 5 days using different doses and dosing regimens of G-CSF/IgG1-Fc or G-CSF and circulating neutrophil levels in the animals measured on Day 6. G-CSF/IgG1-Fc stimulated greater increases in blood neutrophils than comparable doses of G-CSF when administered using daily, every other day or every third day dosing regimens. In rats made neutropenic with cyclophosphamide, G-CSF/IgG1-Fc accelerated recovery of blood neutrophils to normal levels (from Day 9 to Day 5) when administered as 5 daily injections or as a single injection on Day 1. By contrast, G-CSF accelerated neutrophil recovery when administered as 5 daily injections, but not when administered as a single injection. G-CSF/IgG1-Fc was as effective as PEG-G-CSF at accelerating neutrophil recovery following a single injection in neutropenic rats. G-CSF/IgG1-Fc and G-CSF/IgG4-Fc fusion proteins in which the 7 amino acid linker was deleted also were effective at accelerating neutrophil recovery following a single injection in neutropenic rats. These studies confirm the enhanced in vivo hematopoietic properties of G-CSF/IgG-Fc fusion proteins.
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Fator Estimulador de Colônias de Granulócitos/farmacologia , Hematopoese/efeitos dos fármacos , Fragmentos Fc das Imunoglobulinas/farmacologia , Neutropenia/tratamento farmacológico , Proteínas Recombinantes de Fusão/farmacologia , Animais , Contagem de Células Sanguíneas , Modelos Animais de Doenças , Feminino , Expressão Gênica , Ordem dos Genes , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Fator Estimulador de Colônias de Granulócitos/genética , Fragmentos Fc das Imunoglobulinas/administração & dosagem , Fragmentos Fc das Imunoglobulinas/genética , Contagem de Leucócitos , Camundongos , Neutropenia/etiologia , Neutrófilos/efeitos dos fármacos , Ratos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Fatores de TempoRESUMO
Recombinant interferon alpha-2 (IFN-alpha2) has proven useful for treating a variety of human cancers and viral diseases. IFN-alpha2 has a short circulating half-life in vivo, which necessitates daily or thrice weekly administration to patients. It is possible to extend the circulating half-life of IFN-alpha2 by random modification of lysine residues in the protein with polyethylene glycol (PEG); however, such preparations have heterogeneous structures and low specific activities, and may not provide optimal therapeutic benefits to patients. A long-acting, site-specific, monoPEGylated IFN-alpha2 protein has now been created by targeted attachment of a 20 kDa or a 40 kDa maleimide-PEG to a cysteine analogue of IFN-alpha2, M111C. In vitro bioactivities of the purified 20 kDa and 40 kDa PEG-M111C proteins were within 2- to 3-fold of those of wild type IFN-alpha2 and 7- to 10-fold better than that of a 40 kDa PEG IFN-alpha2 protein created using nontargeted, amine-PEGylation methodology. The 20 kDa and 40 kDa PEG-M111C proteins demonstrated 26- to 38-fold longer half-lives, respectively, than IFN-alpha2 following subcutaneous administration to rats. The 20 kDa PEG M111C protein inhibited growth of human NIH:OVCAR-3 cells transplanted into nude mice by >90%, as measured by tumor size, tumor weight, and number of animals with detectable tumors at necropsy, and was significantly more effective than a comparable dose of IFN-alpha2. These data extend our previous findings that bioactivity of IFN-alpha2 can be largely preserved by targeted attachment of PEG moieties to nonessential sites in the protein and provide evidence that site-specific PEGylated IFN-alpha2 proteins possess enhanced tumoricidal properties in vivo.