Tratamiento del lupus eritematoso sistémico: mitos, certezas y dudas

Prednisone and long-term damage in systemic lupus erythematosus: Which is the threshold dose? A pilot study

OBJECTIVES

We aimed to study the daily dose of glucocorticoids in the first month associated with damage after 5 years of systemic lupus erythematosus (SLE) diagnosis; and to assess the daily dose of prednisone during the first year, over which damage after 5 years could be predicted.

METHODOLOGY

A retrospective cohort study of SLE patients from the diagnosis and up to 5 years of follow-up was performed. Cumulative prednisone doses in the first month (T1m), at 1 year (T12m), and at 5 years (T5y) were calculated. Damage was estimated using the SLICC index and activity by the SLEDAI-2K. Damage at T5y was categorized as "present" or "absent". To determine the cutoff point of prednisone dose for the first month and for the first year of treatment, related to damage at 5 years, a ROC curve was done. A logistic regression was performed to control damage at 5 years by the activity levels, anti-DNA titers, and the corticosteroid burden between 1 and 5 years.

RESULTS

Forty-eight patients were included with a mean age of 42.4 (12.6) years; 46 (95.8%) were female. The cumulative dose in T1m associated with greater sensitivity and specificity in the ROC curve (1.54; AUC 0.793; 95% CI: 0.66-0.92) to predict glucocorticoid-related damage at 5 years of follow-up was 980mg, which leads to a daily dose for the first month of 32.6 mg/day. The daily dose during the first year associated with damage at 5 years, allowed to calculate an optimal cutoff point of 7.38 mg/day, with a sensitivity of 92.9% (AUC 0.695, 95% CI: 0.52-0.86) to predict damage at 5 years. In the logistic regression, this estimate was maintained, controlling for SLEDAI-2K and for positivity or not of anti-DNA antibodies and for the cumulative dose of prednisone between T5y and T12m.

CONCLUSION

This pilot study allows to estimate a threshold dose of 32.6 mg/day during the first month and 7.38 mg/day during the first year, over which the risk of permanent damage is high at 5 years, regardless of the activity levels and the glucocorticoid doses considered between the first and the fifth year of follow-up.

Glucocorticoids in Systemic Lupus Erythematosus. Ten Questions and Some Issues

Since the discovery of glucocorticoids (GCs), their important anti-inflammatory effect, rapid mechanism of action, low cost, and accessibility have made them one of the mainstays of treatment for Systemic lupus erythematosus (SLE). Although their use has allowed controlling the disease and reducing acute mortality in severe conditions, the implementation of a scheme based on high doses for long periods has inevitably been accompanied by an increase in adverse effects and infections, including long-term damage. The objective of this review is to answer some important questions that may arise from its use in daily clinical practice, and to propose a paradigm based on the use of methylprednisolone pulses followed by medium-low doses and a rapid decrease of prednisone.

Comparison of two high doses of oral methylprednisolone for multiple sclerosis relapses: a pilot, multicentre, randomized, double-blind, non-inferiority trial

BACKGROUND AND PURPOSE

Oral or intravenous methylprednisolone (≥500 mg/day for 5 days) is recommended for multiple sclerosis (MS) relapses. Nonetheless, the optimal dose remains uncertain. We compared clinical and radiological effectiveness, safety and quality of life (QoL) of oral methylprednisolone [1250 mg/day (standard high dose)] versus 625 mg/day (lesser high dose), both for 3 days] in MS relapses.

METHODS

A total of 49 patients with moderate to severe MS relapse within the previous 15 days were randomized in a pilot, double-blind, multicentre, non-inferiority trial (ClinicalTrial.gov, NCT01986998). The primary endpoint was non-inferiority of the lesser high dose by Expanded Disability Status Scale (EDSS) score improvement on day 30 (non-inferiority margin, 1 point). The secondary endpoints were EDSS score change on days 7 and 90, changes in T1 gadolinium-enhanced and new/enlarged T2 lesions on days 7 and 30, and safety and QoL results.

RESULTS

The primary outcome was achieved [mean (95% confidence interval) EDSS score difference, -0.26 (-0.7 to 0.18) at 30 days (P = 0.246)]. The standard high dose yielded a superior EDSS score improvement on day 7 (P = 0.028). No differences were observed in EDSS score on day 90 (P = 0.352) or in the number of T1 gadolinium-enhanced or new/enlarged T2 lesions on day 7 (P = 0.401, 0.347) or day 30 (P = 0.349, 0.529). Safety and QoL were good at both doses.

CONCLUSIONS

A lesser high-dose oral methylprednisolone regimen may not be inferior to the standard high dose in terms of clinical and radiological response.

Intravenous pulses of methylprednisolone to treat flares of immune-mediated diseases: how much, how long?

Introduction Glucocorticoids are widely used in the treatment of immune-mediated diseases. Despite their widespread use, details on dosing, effectiveness and adverse effects are yet to be determined. Objective To know the current use of methylprednisolone (MTP) in the management of immune-mediated conditions, evaluating the relationship among doses, therapeutic response and adverse effects. Methodology A multicenter retrospective cohort study was designed, including patients who received intravenous pulses of MTP between 1 January 2013 and 12 December 2015 in three different hospitals in Uruguay. The patients included received MTP to treat systemic autoimmune diseases (SADs), hematological, nephrological and neurologic diseases and others. The following variables were analyzed: age, gender, MTP cumulative dose, duration of treatment, clinical response (complete, partial and no response) and adverse effects. Results In total, 164 cases were identified, of which 118 (72%) were female. The median age was 48.4 (SD: 18) years. The indications for MTP included: neuroimmune-mediated 92 (56.1%), SADs 29 (17.5%), hematological 15 (9.1%), nephrological 12 (7.3%) and others 16 (9.9%). The median dose to achieve complete response was 3.2 g (SD: 1.5); the median dose to accomplish a partial response was 3.5 g (SD: 1.25); the median dose for non-responders was 3.3 g (SD 1.2) ( p > 0.05). The median dose in those patients with adverse effects was 3.4 g (SD 1.5) and the median dose for those who did not experience adverse effects was 3.3 g (SD: 1.3) ( p > 0.05). The most frequent adverse effects were infectious (22/164, 13.4%). Diabetics were found to have the highest incidence of adverse effects (13/16, 81%) in comparison to non-diabetics, p < 0.05. Discussion Our study suggests a wide range of doses and duration of treatments with MTP. No major associations were found between clinical response and the use of high MTP doses, but the latter was associated with a large proportion of severe infections. No severe infections were identified with MTP doses lower than 1.5 g. The diabetic population is known to be at risk of experiencing varied adverse effects to MTP. These observations reinforce the need for protocolized use of MTP in order to achieve a better relationship among doses, effectiveness and safety profile.

Clinical Pharmacokinetics and Pharmacodynamics of Biologic Therapeutics for Treatment of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease with potentially severe clinical manifestation that mainly affects women of child-bearing age. Patients who do not respond to standard-of-care therapies, such as corticosteroids and immunosuppressants, require biologic therapeutics that specifically target a single or multiple SLE pathogenesis pathways. This review summarizes the clinical pharmacokinetic and pharmacodynamic characteristics of biologic agents that are approved, used off-label, or in the active pipeline of drug development for SLE patients. Depending on the type of target, the interacting biologics may exhibit linear (non-specific) or non-linear (target-mediated) disposition profiles, with terminal half-lives varying from approximately 1 week to 1 month. Biologics given by subcutaneous administration, which offers dosing flexibility over intravenous administration, demonstrated a relatively slow absorption with a time to maximum concentration of approximately 1 day to 2 weeks and a variable bioavailability of 30-82 %. The population pharmacokinetics of monoclonal antibodies were best described by a two-compartment model with central clearance and steady-state volume of distribution ranging from 0.176 to 0.215 L/day and 3.60-5.29 L, respectively. The between-subject variability in pharmacokinetic parameters were moderate (20-79 %) and could be partially explained by body size. The development of linked pharmacokinetic-pharmacodynamic models incorporating SLE disease biomarkers are an attractive strategy for use in dosing regimen simulation and optimization. The relationship between efficacy/adverse events and biologic concentration should be evaluated to improve clinical trial outcomes, especially for biologics in the advanced phase of drug development. New strategies, such as model-based precision dosing dashboards, could be utilized to incorporate information collected from therapeutic drug monitoring into pharmacokinetic/pharmacodynamic models to enable individualized dosing in real time.

Age of onset influences on clinical and laboratory profile of patients with systemic lupus erythematosus

The present study aims to evaluate differences in clinical and laboratory manifestations and medication use in the different ages of disease onset in patients with systemic lupus erythematosus (SLE). This cross-sectional study consisted of 598 SLE patients (550 female and 48 male), who attended the Rheumatology Clinic of the Hospital de Clínicas de Porto Alegre between 2003 and 2015. Demographic, clinical and laboratory data were collected. The patients were classified into three groups according to their ages at disease diagnosis. Mean age of diagnosis was 33.6 ± 14.3 years, and the median (25th-75th percentile) disease duration was 13 (7-20) years. Among the patients studied, 419 (70%) were adult-onset (aSLE), 90 (14.8%) were late-onset (lSLE) and 89 (14.8%) were childhood-onset (cSLE). The female to male ratio was higher in aSLE (18:1) compared to the other groups (p = 0.001). Arthritis was predominantly found in aSLE (78.5%) when compared with lSLE (57.7%) (p < 0.001). Nephritis was more common in cSLE (60.6%) than in lSLE (26.6%) (p < 0.001). Median (25th-75th percentile) of SLE disease activity index (SLEDAI) was higher in the cSLE group [2 (0-5)] when compared to the lSLE group [0 (0-4)] (p = 0.045). Childhood-onset SLE showed a more severe disease due to the higher incidence of nephritis and needed a more aggressive treatment with immunosuppressive drugs.

Effects of triptolide on the pharmacokinetics of cyclophosphamide in rats: a possible role of cytochrome P3A4 inhibition

OBJECTIVE

To evaluate the effect of a 10-day course of triptolide (TP) on rat cytochrome (CY) P3A4 activity, and on the pharmacokinetics of cyclophosphamide (CPA).

METHODS

In the pharmacokinetics experiment, rats were orally given 0.9% NaCl solution (n=5) and TP [1.2 (mg/kg·d)] for 10 days and a single dose of CPA was administered intravenously (100 mg/kg) to rats on day 11. Blood samples were collected up to 4 h at predetermined time intervals, the plasma concentration of CPA was determined by high performance liquid chromatography (HPLC) and pharmacokinetic parameters were determined. In the in vitro CYP3A4 activity inhibition research, rat blank liver microsomes were divided into 3 groups: a control group, a TS (5 μL, 200 μmol/L) with TP (5 μL, 12.5 μmol/L) group, a TS with ketoconazole (5 μL, 1 μmol/L) group. Concentration of 6β-hydroxylated testosterone (6β-OHT) in liver microsomes was measured by HPLC and the activity of CYP 3A4 was calculated through the following formula: Einhibitor/Econtrol × 100%=Cinhibitor/Ccontrol × 100%.

RESULTS

Compared with the control group, the area under the plasma concentration-time curve (AUC0-∞) of CPA was significantly increased by 229.05% pretreated with TP (P<0.01). Peak plasma concentrations (Cmax) of CPA was significantly increased and plasma half-life was correspondingly extended. The CYP3A4 activity was significantly inhibited by ketoconazole 93.5%±0.2% and TP 84.6%±0.3% compared with the control group (P<0.01 and P<0.05, respectively).

CONCLUSION

Our results strongly suggested that long-term oral intake of TP can distinctly inhibit the CYP3A4 activity and this inhibition evidently decrease the formation of toxic metabolites of CPA.