Dose-dependent Pharmacological Response to Rituximab in the Treatment of Antineutrophil Cytoplasmic Antibody-Associated Vasculiti

2021 ◽  
pp. jrheum.210361
Author(s):  
Jason M. Springer ◽  
Ryan S. Funk
Keyword(s):  
B Cell ◽  
Antineutrophil Cytoplasmic Antibody ◽  
High Dose ◽  
Dosing Regimen ◽  
Dosing Interval ◽  
Cell Counts ◽  
Pharmacological Response ◽  
Trough Concentrations ◽  
Cell Repopulation ◽  
Trough Plasma

Objective Rituximab (RTX) is effective in induction and maintenance of remission in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). However, uncertainty remains regarding the optimal maintenance dosing regimen. This work evaluates the relationship between variability in RTX dosing and pharmacological response in AAV. Methods A prospective cohort of AAV patients (n=28) with either GPA (n=23) or MPA (n=5) receiving maintenance RTX therapy were followed in a single tertiary care academic medical center over a 2-year period. Patient demographics, RTX dosing information, and trough plasma RTX levels were collected along with laboratory measures of pharmacologic response, including B-cell counts and ANCA titers. Results RTX dosing information from 94 infusions with 59 trough samples were collected with a mean±SD dose of 640±221 mg, dosing interval of 210±88 days, and trough plasma RTX concentration of 622±548 ng/mL. RTX trough concentrations were associated with RTX dose (ρ=0.60, p<0.0001) and dosing interval (ρ=-0.55, p<0.0001). RTX dosing intensity (mg/d) was associated with RTX trough concentrations (ρ=0.57, p<0.0001). Higher dosing intensities were associated with undetectable B-cell repopulation (p<0.0001), but not negative ANCA titers (p=0.6). Stratification of dosing intensities based on the standard dosing regimen of 500 mg every six months (2.4 to 3.3 mg/d) demonstrated that this regimen was associated with B-cell repopulation in 8 of 17 doses (47%) compared to 0 of 23 doses (0%) with the high-dose regimen (>3.3 mg/d) (p<0.0001). Conclusion RTX maintenance dosing of 500 mg every six months may be inadequate to maintain B-cell depletion in the treatment of AAV.

scholarly journals CD19 Cell Count at Baseline Predicts B Cell Repopulation at 6 and 12 Months in Multiple Sclerosis Patients Treated with Ocrelizumab

2021 ◽  
Vol 18 (15) ◽  
pp. 8163
Author(s):  
Gianmarco Abbadessa ◽  
Giuseppina Miele ◽  
Paola Cavalla ◽  
Paola Valentino ◽  
Girolama Alessandra Marfia ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Count ◽  
Considerable Proportion ◽  
Cell Counts ◽  
Time Scheduling ◽  
Magnetic Resonance Imaging Mri ◽  
Multiple Sclerosis Patients ◽  
Kinetics Of ◽  
Cell Repopulation

Background: The kinetics of B cell repopulation in MS patients treated with Ocrelizumab is highly variable, suggesting that a fixed dosage and time scheduling might be not optimal. We aimed to investigate whether B cell repopulation kinetics influences clinical and radiological outcomes and whether circulating immune asset at baseline affects B cell repopulation kinetics. Methods: 218 MS patients treated with Ocrelizumab were included. Every six months we collected data on clinical and magnetic resonance imaging (MRI) activity and lymphocyte subsets at baseline. According to B cell counts at six and twelve months, we identified two groups of patients, those with fast repopulation rate (FR) and those with slow repopulation rate (SR). Results: A significant reduction in clinical and radiological activity was found. One hundred fifty-five patients had complete data and received at least three treatment cycles (twelve-month follow-up). After six months, the FR patients were 41/155 (26.45%) and 10/41 (29.27%) remained non-depleted after twelve months. FR patients showed a significantly higher percentage of active MRI scan at twelve months (17.39% vs. 2.53%; p = 0,008). Furthermore, FR patients had a higher baseline B cell count compared to patients with an SR (p = 0.02 and p = 0.002, at the six- and twelve-month follow-ups, respectively). Conclusion: A considerable proportion of MS patients did not achieve a complete CD19 cell depletion and these patients had a higher baseline CD19 cell count. These findings, together with the higher MRI activity found in FR patients, suggest that the Ocrelizumab dosage could be tailored depending on CD19 cell counts at baseline in order to achieve complete disease control in all patients.

scholarly journals Repeated low-dose rituximab treatment based on the assessment of circulating B cells in patients with refractory myasthenia gravis

2019 ◽  
Vol 12 ◽  
pp. 175628641987118 ◽  
Author(s):  
Kyomin Choi ◽  
Yoon-Ho Hong ◽  
So-Hyun Ahn ◽  
Seol-Hee Baek ◽  
Jun-Soon Kim ◽  
...  
Keyword(s):  
B Cells ◽  
Myasthenia Gravis ◽  
B Cell ◽  
Low Dose ◽  
Therapeutic Option ◽  
Treatment Protocol ◽  
Induction Treatment ◽  
Clinical Relapse ◽  
Cell Counts ◽  
Cell Repopulation

Background: The objective of this study was to evaluate the efficacy and safety of repeated low-dose rituximab treatment guided by monitoring circulating CD19+ B cells in patients with refractory myasthenia gravis (MG). Methods: Patients with refractory MG who had received rituximab treatment at two teaching hospitals between September 2013 and January 2017 were reviewed retrospectively. The treatment protocol consisted of an induction treatment with low-dose rituximab (375 mg/m2 twice with a 2-week interval), followed by retreatment (375 mg/m2 once). Retreatment was based on either circulating CD19+ B-cell repopulation or clinical relapse. Outcome measures included the MG Foundation of America (MGFA) clinical classification and postintervention status, prednisolone dose, CD19+ B-cell counts, clinical relapse, and adverse effects. Results: Of 17 patients, 11 (65%) achieved the primary endpoint, defined as the minimal manifestation or better status with prednisolone ⩽5 mg/day, after median 7.6 months (range, 2–17 months) following rituximab treatment. Over a median follow up of 24 months (range, 7–49 months), a total of 30 retreatments were undertaken due to clinical relapse without B-cell repopulation ( n = 6), on the basis of B-cell repopulation alone ( n = 16) and both ( n = 8). B-cell recovery appeared to be in parallel with clinical relapse on the group level, although the individual-level association appeared to be modest, with B-cell repopulation observed only at 57% (8/14) of clinical relapses. Conclusions: The repeated low-dose rituximab treatment based on the assessment of circulating B-cell depletion could be a cost-effective therapeutic option for refractory MG. Further studies are needed to verify the potentially better cost-effectiveness of low-dose rituximab, and to identify biomarkers that help optimize treatment in MG patients.

scholarly journals Monitoring B-cell repopulation after depletion therapy in neurologic patients

2018 ◽  
Vol 5 (4) ◽  
pp. e463 ◽  
Author(s):  
Erik Ellwardt ◽  
Lea Ellwardt ◽  
Stefan Bittner ◽  
Frauke Zipp
Keyword(s):  
B Cells ◽  
B Cell ◽  
Cell Depletion ◽  
Close Monitoring ◽  
B Cell Depletion ◽  
Cell Recovery ◽  
Cell Counts ◽  
White Blood Cell Counts ◽  
Anti Cd20 ◽  
Cell Repopulation

ObjectiveTo determine the factors that influence B-cell repopulation after B-cell depletion therapy in neurologic patients and derive recommendations for monitoring and dosing of patients.MethodsIn this study, we determined the association of body surface area (BSA; calculated by body weight and height with the Dubois formula), sex, pretreatment therapy, age, CSF data, and white blood cell counts with the risk and timing of B-cell repopulation, defined as 1% CD19+ cells (of total lymphocytes), following 87 B cell–depleting anti-CD20 treatment cycles of 45 neurologic patients (28 women; mean age ± SD, 44.5 ± 15.0 years).ResultsPatients with a larger BSA had a higher probability to reach 1% CD19+ cells than those with a smaller BSA (p < 0.05) following B-cell depletion therapy, although those patients had received BSA-adapted doses of rituximab (375 mg/m2). Sex, pretreatment, age, CSF data, or absolute lymphocyte and leukocyte counts during treatment did not significantly influence CD19+ B-cell recovery in the fully adjusted models. Intraindividual B-cell recovery in patients with several treatment cycles did not consistently change over time.ConclusionsB-cell repopulation after depletion therapy displays both high inter- and intra-individual variance. Our data indicate that a larger BSA is associated with faster repopulation of B cells, even when treatment is adapted to the BSA. A reason is the routinely used Dubois formula, underestimating a large BSA. In these patients, there is a need for a higher therapy dose. Because B-cell count–dependent therapy regimes are considered to reduce adverse events, B-cell monitoring will stay highly relevant. Patients' BSA should thus be determined using the Mosteller formula, and close monitoring should be done to avoid resurgent B cells and disease activity.

scholarly journals Pharmacokinetics of Tobramycin Administered at the Beginning of Intermittent Hemodialysis Session (ESRD Study)

2021 ◽  
Vol 8 ◽  
pp. 205435812098706
Author(s):  
Marjolaine Giroux ◽  
Nicolas Bouchard ◽  
Anik Henderson ◽  
Lesly Lam ◽  
Van Anh Sylvie Tran ◽  
...  
Keyword(s):  
Low Dose ◽  
Area Under The Curve ◽  
Compartment Model ◽  
Pharmacokinetic Profile ◽  
High Dose ◽  
Intermittent Hemodialysis ◽  
Dosing Regimen ◽  
Gram Negative ◽  
Trough Concentrations ◽  
Trough Levels

Background and Objectives: There is a renewed interest in the successful use of aminoglycosides due to increasing resistance in gram-negative infections. Few studies to date have examined the pharmacokinetics (PK) of intradialytic infusions of tobramycin. This study sought to characterize the pharmacokinetic profile of intradialytically administered tobramycin in infected patients receiving chronic intermittent hemodialysis and to determine whether it is possible to achieve favorable PK targets. Design, Setting, Participants, and Measurements: In this prospective pharmacokinetic study, a single dose (5 mg/kg) of tobramycin was administered intradialytically to 11 noncritically ill patients undergoing chronic intermittent hemodialysis. Blood samples were collected at selected time to determine tobramycin serum concentrations. The PK analysis was performed using Phoenix™ NLME. The efficacy exposure outcome for nonsevere gram-negative infections sensitive to tobramycin with a minimum inhibitory concentration ≤1 were maximum concentration (Cmax ≥ 10 mg/L) and area under the curve (AUC24 h > 30 mg⋅h/L). For toxicity, the goal was to identify plasma trough concentrations <2 mg/L. Results: Tobramycin disposition was best described by a one-compartment model using a total clearance composed of the systemic clearance and a transitory hemodialysis clearance. Tobramycin mean (SD) Cmax, trough levels, and AUC24h were 13.1 (1.3) mg/L, 1.32 (0.47) mg/L, and 61 (23) mg⋅h/L, respectively. Monte Carlo simulation run with 1000 virtual patients showed that a 5 mg/kg dose of tobramycin administered intradialytically can outperformed the usual low-dose postdialysis dosing (80% meeting all targets versus <1%, respectively). Conclusions: A single high dose of tobramycin can achieve favorable PK outcome when administered using intradialytic infusions in hemodialysis patients. This practical dosing regimen may represent an effective and safer alternative to the usual dosing in the treatment of nonsevere gram-negative infections.

scholarly journals Determining the best window for BNT162b2 mRNA vaccination for SARS-CoV-2 in patients with multiple sclerosis receiving anti-CD20 therapy

2021 ◽  
Vol 7 (4) ◽  
pp. 205521732110621
Author(s):  
Audrey Rico ◽  
Laetitia Ninove ◽  
Adil Maarouf ◽  
Clémence Boutiere ◽  
Pierre Durozard ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
B Cells ◽  
B Cell ◽  
Serologic Response ◽  
Cell Counts ◽  
Anti Cd20 ◽  
Cell Proportion ◽  
Cell Repopulation

We studied the serologic response to the BNT162b2 mRNA vaccine at four weeks after the second dose in patients with RRMS treated with rituximab with extended-interval dosing ( n = 26). At four weeks, 73% of patients were seropositive. No patient without B cells at the first dose ( n = 4) was seropositive. Four of seven (57%) patients with B-cell proportion >0% and ≤5% were seropositive. All patients with B-cell proportion >5% ( n = 15) were seropositive. In all patients, quantitative ELISA measures after vaccination were correlated with B-cell counts measured before vaccination. In patients receiving rituximab, seropositivity after BNT162b2 mRNA vaccination emerged only after B-cell repopulation.

scholarly journals Consequences of VanE-Type Resistance on Efficacy of Glycopeptides In Vitro and in Experimental Endocarditis Due toEnterococcus faecalis

2001 ◽  
Vol 45 (10) ◽  
pp. 2826-2830 ◽  
Author(s):  
Matthieu Lafaurie ◽  
Bruno Perichon ◽  
Agnes Lefort ◽  
Claude Carbon ◽  
Patrice Courvalin ◽  
...  
Keyword(s):  
Standard Dose ◽  
Plasma Concentrations ◽  
High Dose ◽  
Dosing Regimen ◽  
Dosing Interval ◽  
Gentamicin Treatment ◽  
Type Strains ◽  
Level Resistance

ABSTRACT The consequences on glycopeptide activity of low-level resistance to vancomycin due to VanE-type resistance were evaluated in vitro and in experimental endocarditis caused byEnterococcus faecalis BM4405 (MICs of vancomycin and teicoplanin: 16 and 0.5 μg/ml, respectively), its susceptible derivative BM4405-1, and susceptible E. faecalis JH2-2. After 24 h of incubation, vancomycin at 8 μg/ml was not active against E. faecalis BM4405 whereas it was bacteriostatic against strains BM4405-1 and JH2-2. Against all three strains, vancomycin at 30 μg/ml and teicoplanin at 8 or 30 μg/ml were bacteriostatic but bactericidal when combined with gentamicin. In rabbits with aortic endocarditis due to VanE-type resistant strain BM4405, treatment with a standard dose of vancomycin generated subinhibitory plasma concentrations (i.e., peak of 36.3 ± 2.1 μg/ml and trough of 6.0 ± 2.2 μg/ml) and led to no significant reduction in mean aortic valve vegetation counts compared to no treatment of control animals. In contrast, a higher dosing regimen of vancomycin (i.e., resulting in a peak of 38.3 ± 5.2 μg/ml and a trough of 15.0 ± 8.3 μg/ml), providing plasma concentrations above the MIC for the entire dosing interval, led to significant and similar activities against all three strains, which were enhanced by combination with gentamicin. Treatment with teicoplanin led to results similar to those obtained with vancomycin at a high dose. No subpopulations with increased resistance to glycopeptides were selected in vitro or in vivo. In conclusion, the use of a high dose of vancomycin was necessary for the treatment of experimental enterococcal endocarditis due to VanE-type strains.

scholarly journals Impact of High-Dose Methotrexate on the Outcome of Patients with Diffuse Large B-Cell Lymphoma and Skeletal Involvement

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2945
Author(s):  
Mélanie Mercier ◽  
Corentin Orvain ◽  
Laurianne Drieu La Rochelle ◽  
Tony Marchand ◽  
Christopher Nunes Gomes ◽  
...  
Keyword(s):  
B Cell ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
High Dose ◽  
High Dose Methotrexate ◽  
Skeletal Involvement ◽  
Large B Cell Lymphoma ◽  
Dose Methotrexate ◽  
The Impact ◽  
Large B Cell

Diffuse large B-cell lymphoma (DLBCL) with extra nodal skeletal involvement is rare. It is currently unclear whether these lymphomas should be treated in the same manner as those without skeletal involvement. We retrospectively analyzed the impact of combining high-dose methotrexate (HD-MTX) with an anthracycline-based regimen and rituximab as first-line treatment in a cohort of 93 patients with DLBCL and skeletal involvement with long follow-up. Fifty patients (54%) received upfront HD-MTX for prophylaxis of CNS recurrence (high IPI score and/or epidural involvement) or because of skeletal involvement. After adjusting for age, ECOG, high LDH levels, and type of skeletal involvement, HD-MTX was associated with an improved PFS and OS (HR: 0.2, 95% CI: 0.1–0.3, p < 0.001 and HR: 0.1, 95% CI: 0.04–0.3, p < 0.001, respectively). Patients who received HD-MTX had significantly better 5-year PFS and OS (77% vs. 39%, p <0.001 and 83 vs. 58%, p < 0.001). Radiotherapy was associated with an improved 5-year PFS (74 vs. 48%, p = 0.02), whereas 5-year OS was not significantly different (79% vs. 66%, p = 0.09). A landmark analysis showed that autologous stem cell transplantation was not associated with improved PFS or OS. The combination of high-dose methotrexate and an anthracycline-based immunochemotherapy is associated with an improved outcome in patients with DLBCL and skeletal involvement and should be confirmed in prospective trials.

High survival rate in advanced-stage B-cell lymphomas and leukemias without CNS involvement with a short intensive polychemotherapy: results from the French Pediatric Oncology Society of a randomized trial of 216 children.

1991 ◽  
Vol 9 (1) ◽  
pp. 123-132 ◽  
Author(s):  
C Patte ◽  
T Philip ◽  
C Rodary ◽  
J M Zucker ◽  
H Behrendt ◽  
...  
Keyword(s):  
Survival Rate ◽  
B Cell ◽  
Pediatric Oncology ◽  
Stage Iv ◽  
High Dose ◽  
High Survival ◽  
Advanced Stage ◽  
High Survival Rate ◽  
Cns Involvement

From April 1984 to December 1987, the French Pediatric Oncology Society (SFOP) organized a randomized trial for advanced-stage B-cell lymphoma without CNS involvement to study the possibility of reducing the length of treatment to 4 months. After receiving the same three intensive six-drug induction courses based on high-dose fractionated cyclophosphamide, high-dose methotrexate (HD MTX), and cytarabine in continuous infusion, patients were evaluated for remission. Those who achieved complete remission (CR) were randomized between a long arm (five additional courses with two additional drugs; 16 weeks of treatment) and a short arm (two additional courses; 5 weeks). For patients in partial remission (PR), intensification of treatment was indicated. Two hundred sixteen patients were registered: 15 stage II nasopharyngeal and extensive facial tumors, 167 stage III, and 34 stage IV, 20 of the latter having more than 25% blast cells in bone marrow. The primary sites of involvement were abdomen in 172, head and neck in 30, thorax in two, and other sites in 12. One hundred sixty-seven patients are alive in first CR with a minimum follow-up of 18 months; four are lost to follow-up. Eight patients died from initial treatment failure, 14 died from toxicity or deaths unrelated to tumor or treatment, and 27 relapsed. The event-free survival (EFS), with a median follow-up of 38 months, is 78% (SE 3) for all the patients, 73% (SE 11) for the stage II patients, 80% (SE 3) for the stage III patients, and 68% (SE 8) for the stage IV and acute lymphoblastic leukemia (ALL) patients. One hundred sixty-six patients were randomized: 82 in the short arm and 84 in the long arm. EFS is, respectively, 89% and 87%. Statistical analysis confirms equivalence of both treatment arms with regard to EFS. Moreover, morbidity was lower in the short arm. This study confirms the high survival rate obtained in the previous LMB 0281 study without radiotherapy or debulking surgery and demonstrates the effectiveness of short treatment.

​Safety Evaluation of Andrographolide-nanosuspensions

2021 ◽  
Author(s):  
Haigang Wu ◽  
Jia Liu ◽  
Zhaowei Ye ◽  
Jinni Liu ◽  
Li Huang ◽  
...  
Keyword(s):  
Toxicity Test ◽  
Dose Group ◽  
In Vitro Release ◽  
Liver Cells ◽  
Precipitation Method ◽  
Hepatic Veins ◽  
High Dose ◽  
Interstitial Tissue ◽  
Renal Tubules ◽  
Cell Counts

Background: Andrographolide (ANDRO) is a hydrophobic drug, which faces the problem of limited absorption due to poor water solubility. The current research prepared andrographolide nanosuspensions (ANDRO-NS) and examined in vivo toxicity for mice. Methods: ANDRO-NS were prepared by anti-solvent precipitation method, transmission electron micrographs, granularity analysis and in vitro release were used to characterize the ANDRO-NS, we evaluate the safety of the ANDRO-NS by using the acute toxicity test, local irritation test and chronic toxicity test. Result: The particle size of ANDRO-NS was (568.51±13.74 nm). The LD50 for ANDRO-NS was 548.91 mg/kg after oral administration to KM mice with a 95% CI of 468.19-645.03 mg/kg. The white blood cell counts and hemoglobin levels for the experimental groups were lower than controls receiving only saline. Serum aspartate transaminase, creatinine and blood urea nitrogen levels were greater than controls after 7 and 14 days of once-daily administration. After 14 days of administration, the platelet counts as well asalanine transaminase levels were, in addition, Histological observations indicated that interstitial kidney tissues were wider than controls and showed episodic bleeding after 7 days of administration. The highest dose administered also resulted in the dilation and blood engorgement of the central hepatic veins with some severed hepatic cords. Mice receiving the lowest dose of ANDRO-NS we administered appeared healthy and similar to controls receiving saline only. Following 14 days of administration, we found significant vacuolar degeneration of renal tubular epithelial cells and glomerular atrophy for the high-dose group as well as edema and necrosis in liver cells. The medium-dose group displayed kidney interstitial tissue widening with scattered bleeding, inflammatory cell infiltration and hepatocyte edema. The low-dose group displayed dilated renal tubules and irregularly-arranged liver cells as well as bleeding in the hepatic sinusoids. Therefore, short-term administration of andrographolide suspensions resulted in inflammation and time- and dose-dependent toxic effects on the kidneys and liver.

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