Combination of rituximab and methotrexate followed by rituximab and cytarabine in elderly patients with primary central nervous system lymphoma.

The optimal treatment strategy for newly diagnosed primary central nervous system lymphoma (PCNSL) has yet to be established, especially in the elderly. In the current study, we conducted a phase II study to evaluate the efficacy and safety of rituximab plus high-dose MTX followed by rituximab plus cytarabine in patients aged ≥60 years newly diagnosed with PCNSL. Patients received an induction treatment of high-dose methotrexate plus rituximab followed by two cycles of a consolidation treatment of cytarabine plus rituximab. The primary end-point was a 2-year progression-free survival (PFS) rate. A total of 35 patients were recruited, and their median age was 73 (range: 60-81). After induction treatment, the complete and partial responses (PRs) were 56% and 20% respectively. Twenty-six patients proceeded to the consolidation treatment; the complete and PRs were 59% and 9% respectively. After a median follow-up duration of 36.0 months, the 2-year PFS rate was 58.7%. Treatment was generally well-tolerated as only three patients were withdrawn from the study due to toxicity, and no treatment-related mortality was reported. The 2-year overall survival rate was 77.9%. The current study may suggest the feasibility of administering high-dose MTX plus cytarabine in PCNSL patients aged ≥60 years and the potential role of additive rituximab.

Impact of concomitant methotrexate on disease activity in patients with rheumatoid arthritis tapering abatacept: results from KOBIO registry.

Objectives: Tapering biologic agents can be considered for patients with stable disease activity in rheumatoid arthritis (RA). However, the specific strategy for abatacept is uncertain. This study aimed to examine the impact of tapering abatacept on disease activity in RA patients and assess the potential influence of concomitant methotrexate (MTX) treatment. Methods: Using data from the KOBIO registry, we included 505 1 year intervals from 176 patients with RA that initiated abatacept with concomitant MTX at baseline. The intervals were divided into two groups based on the dose quotient (DQ) of abatacept during each period (i.e., the tapering group (DQ < 1) and control group (DQ = 1)). The primary outcome was achieving DAS28-remission at 1 year intervals. Marginal structural models (MSM) were used to minimize confounding caused by an imbalance in time-varying variables. Results: Abatacept was tapered at 146 (28.9%) intervals, and the mean DQ was 0.68. DAS28-remission was achieved in 207 (41.8%) intervals. Tapering abatacept did not affect the odds of achieving DAS28-remission compared with the control group (OR 1.04 [0.67-1.62]). The odds remained unaffected in the subgroup that continued MTX (OR 1.42 [0.88-2.30]) but not in the subgroup that discontinued MTX (OR 0.26 [0.10-0.57]). The effects of interaction between tapering abatacept and concomitant MTX use on DAS28 and patient's functional status showed consistent results. The incidence of adverse events within a 1 year interval was comparable between the two groups. Conclusion: Withdrawal of MTX while tapering abatacept may compromise meeting the treatment goal for patients with RA.

A Case Report on Iatrogenic Methotrexate Toxicity.

This case study studies the adverse effects of methotrexate toxicity as well as the importance of early recognition of the symptoms and signs of methotrexate toxicity. This study involves a 54-year-old female who accidentally took methotrexate in high doses for a period of five consecutively days. The patient had been diagnosed with mixed connective tissue disease and was being treated with methotrexate once weekly. However, she took 7.5 mg (three tablets) three times a day for five days instead of 15 mg once weekly in two divided doses. The patient immediately went to the ER but was asymptomatic and discharged after a CBC showed values within the normal range. The patient was then seen by her primary care physician and advised to return to the ER. At this time, the patient had mucocutaneous lesions and was complaining of oral and throat pain, and a repeat CBC demonstrated pancytopenia. The patient was admitted to the hospital for further management and treatment of methotrexate toxicity.

Successful Management of Cervical and Tubal Stump Double Pregnancy after Assisted Reproductive Technologies Using Multiple High Doses of Methotrexate: A Case Report.

The incidence of ectopic pregnancy (EP) has increased in recent years, owing to causes such as pelvic inflammatory diseases and assisted reproductive technologies (ART). The present study reported a case of a 33-year-old nulliparous woman with a history of previous ectopic pregnancies, who underwent pelvic ultrasound in August 2022, which revealed a double EP including a cervical pregnancy and a tubal stump pregnancy. Despite known risk factors and elevated beta-human chorionic gonadotropin (ß-hCG) levels, a conservative approach, utilizing multiple doses of systemic methotrexate (MTX) injections, was employed to preserve fertility at the Regional Perinatal Center in Aktobe, Kazakhstan. Treatment efficacy was monitored through ß-hCG levels and ultrasound imaging, with successful resolution of both EPs and preservation of reproductive function. The present case highlighted the safety and efficacy of MTX therapy in managing complex EP presentations, emphasizing the necessity of individualized treatment approaches in reproductive medicine, particularly in terms of preserving fertility in patients undergoing ART. Multiple high doses of MTX injections were beneficial for pregnancy with two distinct regions, fetal cardiac activity, and elevated serum ß-hCG level. Further research is required to explore optimal treatment strategies for EP, considering patient-specific factors and treatment goals.

Central nervous system prophylaxis in large B-cell lymphoma: A British Society for Haematology Good Practice Paper.

This Good Practice Paper provides recommendations for the baseline investigation, risk stratification and use of prophylactic interventions for patients with large B-cell lymphoma at risk of central nervous system relapse. Recent evidence which has questioned the role of high-dose methotrexate in this clinical scenario is discussed in detail.

Treatment with Targeted Therapy in Patients with Psoriatic Arthritis and Inadequate Response to Methotrexate: Proposal for a Rational Strategy.

INTRODUCTION: The therapeutic arsenal for psoriatic arthritis (PsA) is gradually being expanded, but the use of these targeted treatments must be optimal. Our objective was to guide the choice of targeted therapy to use as first-line treatment in a patient with PsA in whom methotrexate (MTX) has failed. METHODS: We searched for literature data in PubMed with the appropriate keywords for the six points of our argument: (1) the tolerance of MTX; (2) the efficacy of targeted therapies combined with MTX vs monotherapy; (3) immunogenicity of anti-tumor necrosis alpha (TNFα) monoclonal antibodies (mAbs); (4) immunogenicity of anti-interleukin (IL)-17, anti-IL-12/23, and anti-IL-23 mAbs; (5) the therapeutic maintenance of anti-TNFα mAbs when combined or not with MTX; (6) the therapeutic maintenance of anti-IL-17 vs anti-TNFα mAbs as first-line targeted therapy. RESULTS: The proposed rational strategy is as follows: in case of initiation of an anti-TNFα agent, maintaining treatment with MTX seems preferable, even in the absence of evidence of the superior efficacy of the combination, to avoid immunization and reduced therapeutic maintenance; in case of initiation of anti-IL-17, anti-IL-12/23, anti-IL-23 agents, or Janus kinase (JAK) inhibitors, again in the absence of evidence of the superior efficacy of the combination, discontinuing MTX therapy may be possible, at least in two steps, after verifying the efficacy of the targeted therapy initiated on the joints and skin. CONCLUSION: We have data from the literature to guide the choice of targeted therapy to use as first-line treatment in a patient with PsA in whom MTX has failed.

Corrigendum: Methotrexate-conjugated zinc oxide nanoparticles exert substantially improved cytotoxic effect on lung cancer cells by inducing apoptosis.

[This corrects the article DOI: 10.3389/fphar.2023.1194578.].

[TruClear™ treatment of caesarean scar pregnancy interrupted after methotrexate injection]. / Résection mécanique hystéroscopique de résidus trophoblastique d'une grossesse sur cicatrice de césarienne après injection de méthotrexate.

BACKGROUND: Cesarean scar pregnancy is a complicated and potentially life-threatening type of ectopic pregnancy. There is no gold standard for its management. The aim is to demonstrate the efficacy and safety of treatment by hysteroscopic tissue removal system after systemic methotrexate injection. METHODS: We report the case of a 27-year-old patient who had previously had a C-section and who presented herself to the emergency room with pelvic pain and metrorrhagia. The human chorionic gonadotrophin (hCG) serum level was positive. The exploration revealed an ectopic pregnancy on the cesarean scar. She benefited of 4 systemic injections of methotrexate. As the hCG became negative, endovaginal ultrasound confirmed the avascular nature of the mass. Surgical resection by mechanical morcellation hysteroscopy (TruClear™) was performed under general anaesthesia, visual control and ultrasound guidance. RESULTS: This procedure was successful. It was an ambulatory procedure and there were neither intra- nor postoperative complications. CONCLUSIONS: To our knowledge, this is the first time in Belgium that a hysteroscopic tissue removal system procedure has been used to treat a caesarean scar pregnancy. This technique seems to be safe for both the patient and the surgeon and could become a new approach for cesarean scar pregnancy management.

CONTEXTE: La grossesse sur cicatrice de césarienne est définie comme la présence d'un sac gestationnel dans une isthmocèle créée par une hystérotomie préalable. Il n'existe pas de gold standard concernant sa prise en charge. L'objectif est de démontrer l'efficacité et la sécurité du traitement par résection mécanique hystéroscopique des tissus après injection systémique de méthotrexate. Méthodes : Nous rapportons le cas d'une patiente de 27 ans ayant déjà eu une césarienne et qui s'est présentée aux urgences avec des douleurs pelviennes et des métrorragies. L'exploration révèle une grossesse sur la cicatrice de césarienne. Elle a bénéficié de 4 injections systémiques de méthotrexate. La résection des résidus trophoblastiques avasculaires a été réalisée par voie hystéroscopique en utilisant l'hystéroscope par action mécanique de type -TruClear™ et ce, sous contrôle échographique concomitant. Résultats : Cette procédure ambulatoire effectuée sous anesthésie générale a été un succès. Il n'y a eu aucune complication per- ou postopératoire. CONCLUSIONS: À notre connaissance, c'est la première fois qu'une résection par action mécanique des résidus trophoblastiques sur cicatrice de césarienne est réalisée en Belgique. Cette technique semble sûre pour la patiente et le chirurgien et pourrait devenir une nouvelle approche pour la prise en charge d'une grossesse sur cicatrice de césarienne.

Effectiveness of methotrexate and bridging glucocorticoids with or without early introduction of a 6-month course of etanercept in early RA: results of the 2-year, pragmatic, randomised CareRA2020 trial.

OBJECTIVES: To investigate if patients with early rheumatoid arthritis responding insufficiently to initial methotrexate (MTX) and bridging glucocorticoids (GCs) could benefit from early but temporary etanercept introduction as a second remission-induction attempt. METHODS: CareRA2020 (NCT03649061) was a 2-year, open-label, multicentre, pragmatic randomised controlled trial. Treatment-naïve patients started MTX and GC bridging (COBRA-Slim: CS). Within a time window from week (W) 8 until W32, early insufficient responders (28-joint Disease Activity Score - C-reactive Protein (DAS28-CRP) >3.2 between W8 and W32 or ≥2.6 at W32) were randomised to a Standard-CS strategy (adding leflunomide first) or Bio-induction-CS strategy (adding etanercept for 24 weeks). Additional treatment adaptations followed the treat-to-target principle. Longitudinal disease activity (DAS28-CRP) over 104 weeks (primary outcome), achievement of DAS28-CRP <2.6 28 weeks after randomisation, and biologic or targeted synthetic disease-modifying antirheumatic drug (b/tsDMARD) use at W104 were compared between randomisation groups. RESULTS: Following CS treatment, 142 patients were early responders; 55 early insufficient responders received Standard-CS and 55 Bio-induction-CS. Superiority of Bio-induction-CS over Standard-CS could not be demonstrated (ß=-0.204, (95% CI -0.486 to 0.078), p=0.157) for the primary outcome. More patients on Bio-induction-CS achieved DAS28-CRP <2.6 at 28 weeks after randomisation (59% (95% CI 44% to 72%) vs 44% (95% CI 31% to 59%) in Standard-CS) and they were treated less frequently with b/tsDMARDs at W104 (19/55, 35%) compared with Standard-CS (29/55, 53%). CONCLUSION: Half of the patients responded well to initial COBRA-Slim induction therapy. In early insufficient responders, adding etanercept for 6 months did not improve disease control over 104 weeks versus adding leflunomide first. However, temporary introduction of etanercept resulted in improved disease control early after randomisation and less patients on b/tsDMARDs at W104. TRIAL REGISTRATION NUMBER: NCT03649061. CTR PILOT APPROVAL BELGIUM: S59474, EudraCT number: 2017-004054-41.

Methotrexate and Rituximab Use in Highly Recurrent Idiopathic Subglottic Stenosis.

OBJECTIVE: To evaluate the impact of methotrexate and rituximab therapy on highly recurrent idiopathic subglottic stenosis (iSGS) patients with a negative antineutrophil cytoplasmic antibody titer cANCA(-). METHODS: This was a retrospective cohort study of highly recurrent iSGS patients who recurred within 1 year or less and were treated with methotrexate (MTX), and rituximab (RTX), or a combination of both at different time points (MTX/RTX). Average surgical durations before and after drug treatment were summarized, and the differences were calculated. RESULTS: A total of 21 female patients with median age of 62 years were included. Fifteen patients were treated with MTX, three were treated with RTX, and five treated with both. Patients treated with immunosuppressants showed a trend toward longer intervals between operations (mean pre-drug interval: 338; mean post-drug interval: 697 days) (p-value = 0.25). Three patients did not recur following drug initiation with median follow-up of 1265 days. All three treatment groups demonstrated a trend toward increased post-drug recurrence intervals (MTX: 444 days, RTX: 374 days, MTX/RTX: 55 days), that was not statistically significant. Patients with prior dilations demonstrated longer post-drug recurrence intervals (mean pre-drug interval: 341 days, mean post-drug interval 978 days) (p-value = 0.17). Four patients in the cohort with the highest recurring disease improved from mean 129 days between operations to 509 days with drug therapy. The most common drug side effect was nausea (16%). CONCLUSION: MTX and RTX may be treatment options for some highly recurrent iSGS patients. Initial results are variable and demonstrate a need for further research on drug candidacy. LEVEL OF EVIDENCE: 3 Laryngoscope, 2024.

Characteristics of T-Cell Receptor Repertoire for Differential Response to Methotrexate Treatment for Rheumatoid Arthritis.

BACKGROUND: Methotrexate (MTX) serves as the initial treatment for rheumatoid arthritis (RA). However, a substantial proportion of RA patients, estimated between 30% and 50%, do not respond positively to MTX. While the T-cell receptor (TCR) is crucial for the immune response during RA, its role in differentiating MTX responsiveness has not been thoroughly investigated. METHODS: This study used next-generation sequencing to analyze the TCR ß-chain complementary determining region sequences in peripheral blood mononuclear cells obtained from RA patients before MTX treatment. This study aimed to compare the characteristics of the TCR repertoire between the MTX responder and non-responder groups. RESULTS: The study identified a significant difference in the TRBV6-6 gene (p = .003) concerning MTX treatment response. Additionally, a significant difference was found in the number of "3" nucleotide deletions at the 5'Jdels site (p = .023) in the VDJ rearrangement. CONCLUSION: These findings suggest distinct TCR repertoire characteristics between MTX responder and non-responder groups among RA patients. This discovery offers new insights into understanding the variable responses of RA patients to MTX therapy.

Electroacupuncture and methotrexate cooperate to ameliorate psoriasiform skin inflammation by regulating the immune balance of Th17/Treg.

Psoriasis is an autoinflammatory dermatosis, while methotrexate (MTX) is an immunosuppressant used to treat psoriasis. However, conventional immunosuppressants may cause various side effects. Acupuncture has potential benefits in treating psoriasis based on its anti-inflammatory effects. However, the immune mechanisms underlying its effects remain unclear. In this study, imiquimod-induced psoriatic mice were used to investigate the effects and mechanisms of electroacupuncture (EA) and, in particular, its joint treatment with MTX. We found that treatment with either EA or MTX ameliorated psoriasiform skin lesions, improved skin pathology and reduced proinflammatory cytokines in the skin, while joint treatment with both EA and MTX further alleviated the skin lesions and inflammation compared to either one alone. Moreover, percentages of CD4+ IL-17A+ Th17 cells in the skin and lymph nodes were decreased by EA or MTX and further lowered by combined EA+MTX treatment. Similarly, EA or MTX also reduced their RORγt expression. On the contrary, CD4+ FoxP3+ Treg frequency in psoriatic mice was augmented by EA or MTX and further increased by the joint treatment. However, depleting Tregs mostly reversed the therapeutic effects of EA or EA plus MTX. Additionally, the phosphorylated NF-κB (p65) expression was suppressed by treatment with EA, MTX or better with EA+MTX. Meanwhile, the anti-inflammatory effects of EA plus MTX were offset by an NF-κB agonist. Thus, this study has revealed that EA cooperates with MTX to balance Th17/Treg responses and to ameliorate psoriasiform skin inflammation through suppressing NF-κB activation. Our findings may be implicated for treating human psoriasis.

FOXM1 mediates methotrexate resistance in osteosarcoma cells by promoting autophagy.

Osteosarcoma (OS) is a primary bone cancer mostly found in adolescents and elderly individuals. The treatment of OS is still largely dependent on traditional chemotherapy. However, the high incidence of drug resistance remains one of the greatest impediments to limiting improvements in OS treatment. Recent findings have indicated that the transcription factor FOXM1 plays an important role in various cancer-related events, especially drug resistance. However, the possible role of FOXM1 in the resistance of OS to methotrexate (MTX) remains to be explored. Here, we find that FOXM1, which confers resistance to MTX, is highly expressed in OS tissues and MTX-resistant cells. FOXM1 overexpression promotes MTX resistance by enhancing autophagy in an HMMR/ATG7-dependent manner. Importantly, silencing of FOXM1 or inhibiting autophagy reverses drug resistance. These findings demonstrate a new mechanism for FOXM1-induced MTX resistance and provide a promising target for improving OS chemotherapy outcomes.

Faster steroid-free remission with tocilizumab compared to methotrexate in giant cell arteritis: a real-life experience in two reference centres.

Glucocorticoids (GCs) are still the mainstay of treatment of giant cell arteritis (GCA). Although GCs are highly effective in GCA, the high burden of toxicity of GCs as well as the disease relapse during GC tapering is well documented. To compare the efficacy and rapidity of TCZ and MTX as steroid-sparing agents in a real-life cohort of GCA patients. A retrospective analysis was conducted including patients with newly diagnosed GCA from the Rheumatology Units of Udine and Rome. The inclusion criterion was the treatment with TCZ or MTX as first steroid-sparing drug. 112 GCA patients (81 females) with a median age of 70 (IQ 65-75) years were collected. Thirty-one out of 112 (27.7%) patients were treated with TCZ (162 mg/week), while 81/112 (72.3%) patients received MTX (up to 20 mg/week) as a GC-sparing agent. At month 6 after GCA onset, 5/31 (16.1%) patients in TCZ group and none in MTX group were in GC-free sustained remission (p value = 0.001). Similarly, at month 12, 64.5% (20/31) and 11.1% (9/81) of patients were in sustained GC-free remission in TCZ and MTX group, respectively (p value <0.001). At month 24 of follow-up, at least one relapse of the disease occurred in 7/31 (22.6%) in TCZ-treated and 28/81 (34.6%) in MTX-treated patients, respectively (p value = 0.22). TCZ allowed a faster discontinuation of steroid therapy than MTX in GCA patients, without increasing the risk of relapse.

Epstein-Barr Virus-Positive Mucocutaneous Ulcer With Medication-Related Osteonecrosis of the Jaw Arising in the Mandible of a Rheumatoid Arthritis Patient: A Case Report.

This study presents a rare case of an Epstein-Barr virus-positive mucocutaneous ulcer (EBVMCU) co-existing with medication-related osteonecrosis of the jaw (MRONJ) in the mandible of a 54-year-old Japanese man who complained of painful swelling of the left mandibular gingiva over the past three months. The patient had a history of methotrexate (MTX) and bisphosphonates (BPs) use. Intraoral examination revealed a 35 mm large ulcerative lesion with marginal gingival swelling and bone exposure on the left side of the mandible. A biopsy was performed, confirming the diagnosis of EBVMCU with MRONJ. Due to the enlargement of the bone exposure, marginal resection of the mandible was performed under general anesthesia as a treatment for residual MRONJ. At the two-year follow-up, no evidence of recurrence was observed.

Cesarean Scar Pregnancy With Surgical and Conservative Managements: A Case Report.

A cesarean scar pregnancy (CSP) is a rare form of ectopic pregnancy. Proper diagnosis and management of CSP are incredibly important secondary to the risk of uterine rupture and life-threatening hemorrhage. Various medical and surgical management have been described previously. This report looks at two cases of CSP diagnosed at an urban hospital in Atlanta, Georgia. The first woman was 30 years old with a history of five prior CS. She was referred from an abortion clinic for CSP at 6 weeks 2 days gestation. She did not desire future fertility and opted for a hysterectomy. The second woman was 38 years old with a history of three prior CS presenting with vaginal bleeding and abdominal pain and found to have a CSP with a gestation sac measuring 5 weeks 1 day. Given the patient's desires for future fertility, she was treated with a two-dose regimen of systemic intramuscular methotrexate (MTX) at 1 mg/kg with successful resolution of CSP and subsequent intrauterine pregnancy. Due to the high risk of uterine rupture and hemorrhage with CSP, it is important to have a high index of suspicion for diagnosis. Due to the rarity of CSP, and thus difficulty creating quality prospective trials, there is no consensus on the best management yet. Although conservative treatment carries high failure risk, shared decision-making incorporating future fertility desires should be considered when determining management of CSP, and when surgical management is considered a minimally invasive approach should be the standard of care in surgical management.

Methotrexate accumulation in target intestinal mucosa and white blood cells differs from non-target red blood cells of patients with Crohn's disease.

BACKGROUND: Intracellular methotrexate polyglutamates (MTX-PGs) concentrations are measurable in red blood cells (RBCs) during MTX treatment. MTX-PG3 concentrations correlate with efficacy in patients with Crohn's disease (CD). Since RBCs are not involved in pathogenesis of CD and lack extended MTX metabolism, we determined MTX-PGs accumulation in peripheral blood mononuclear cells (PBMCs: effector cells) and intestinal mucosa (target cells) and compared those with RBCs as a potential more precise biomarker. METHODS: In a multicentre prospective cohort study, blood samples of patients with CD were collected during the first year of MTX therapy. Mucosal biopsies were obtained from non-inflamed rectum and/or inflamed intestine. MTX-PGs concentrations in mucosa, PBMCs and RBCs were measured by liquid chromatography-tandem mass spectrometry. RESULTS: From 80 patients with CD, a total of 27 mucosal biopsies, 9 PBMC and 212 RBC samples were collected. From 12 weeks of MTX therapy onwards, MTX-PG3 was the most predominant species (33%) in RBCs. In PBMCs, the distribution was skewed towards MTX-PG1 (48%), which accounted for an 18 times higher concentration than in RBCs. Long-chain MTX-PGs were highly present in mucosa: 21% of MTX-PGtotal was MTX-PG5. MTX-PG6 was measurable in all biopsies. CONCLUSIONS: MTX-PG patterns differ between mucosa, PBMCs and RBCs of patients with CD.

A Canadian Retrospective Chart Review Evaluating Concomitant Methotrexate De-escalation Patterns in Patients with Rheumatoid Arthritis Treated with Biologic or Targeted Synthetic DMARDs.

INTRODUCTION: Rheumatoid arthritis (RA) guidelines recommend methotrexate (MTX)-anchored therapy with biologic or targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs); however, tolerability issues often lead to non-adherence. Canadian data on MTX tapering and/or withdrawal following b/tsDMARD initiation are minimal. This chart review assessed frequency of MTX tapering or withdrawal following b/tsDMARD initiation and the impact on disease status in Canadian adults with RA. METHODS: Eligible patients had received MTX for ≥ 3 months before b/tsDMARD initiation. The b/tsDMARD was prescribed continuously for ≥ 18 months. Patients taking > 10 mg/day oral prednisone or equivalent were excluded. RESULTS: Eight hundred eighty-nine patients (mean baseline MTX dose 19.0 mg/week) prescribed b/tsDMARDs (tumor necrosis factor inhibitor 52.1%, Janus kinase inhibitor 18.3%, interleukin-6 inhibitor [IL-6i] 11.9%, other 17.7%) were evaluated at 22 Canadian centers. Within 2 years of b/tsDMARD initiation, MTX was tapered in 123 (13.8%) patients and discontinued in 147 (16.5%), most commonly due to planned tapering (36.6%) and patient decision (27.2%), respectively, and most commonly with IL-6i use (34.9%). The MTX dose was unchanged for 582 (65.5%) patients and increased for 37 (4.2%). Missing data limit interpretations of MTX dose effects on some secondary endpoints and challenge the assertion that a disease activity measure-based treat-to-target approach is routinely used in Canadian rheumatology practice. CONCLUSIONS: Methotrexate tapering or withdrawal occurred in 30.4% of Canadians with RA within 2 years following b/tsDMARD initiation. Baseline disease activity measures were missing from many medical records. However, for patients with baseline assessments, MTX tapering or discontinuation did not worsen disease activity.

Pharmacokinetic-pharmacodynamic modelling and simulation of methotrexate dosing in patients with rheumatoid arthritis.

AIMS: To develop a non-linear mixed-effects population pharmacokinetic and pharmacodynamic (PK-PD) model describing the change in the concentration of methotrexate polyglutamates in erythrocytes (ery-MTX-PGn with "n" number of glutamate, representing PK component) and how this relates to modified 28-joint Disease Activity Score incorporating erythrocyte sedimentation rate (DAS-28-3) for rheumatoid arthritis (RA), representing PD component. METHODS: An existing PK model was fitted to data from a study consisting of 117 RA patients. The estimation of population PK-PD parameters was performed using stochastic approximation expectation maximisation algorithm in Monolix 2021R2. The model was used to perform Monte Carlo simulations of a loading dose regimen (50mg subcutaneous methotrexate as loading doses, then 20mg weekly oral methotrexate) compared to a standard dosing regimen (10mg weekly oral methotrexate for 2 weeks, then 20mg weekly oral methotrexate). RESULTS: Every 40 nmol/L increase in ery-MTX-PG3-5 total concentration correlated with 1-unit reduction in DAS-28-3. Significant covariate effects on the therapeutic response of methotrexate included the use of prednisolone in the first 4 weeks (positive use correlated with 25% reduction in DAS-28-3 when other variables were constant) and patient age (every 10-year increase in age correlated with 3.4% increase in DAS-28-3 when other variables were constant). 4 methotrexate loading doses led to a higher percentage of patients achieving a good/moderate response compared to the standard regimen (Week 4: 87.6% vs. 39.8%; Week 10: 64.7% vs. 57.0%). CONCLUSIONS: A loading dose regimen was more likely to achieve higher ery-MTX-PG concentration and better therapeutic response after 4 weeks of methotrexate treatment.

Systemic methotrexate (MTX) in early pregnancy: a retrospective study of a tertiary maternity hospital.

BACKGROUND: Methotrexate (MTX) is used in clinical practice as a medical treatment option in patients with early pregnancy complications like ectopic pregnancy. AIMS: To review systemic MTX therapy use in the first trimester of pregnancy in our hospital and to examine subsequent clinical outcomes. METHODS: Retrospective review of all women treated with systemic MTX in early pregnancy identified from electronic prescription records from 1 January 2018 to 31 December 2020 at Cork University Maternity Hospital, Ireland. Relevant data was transcribed from electronic health records. RESULTS: Indications for treatment were tubal ectopic pregnancy (70%, n = 51), persistent pregnancy of unknown location (22%, n = 16) and caesarean scar pregnancy (7%, n = 5). Treatment was successful in 88% (n = 44) of tubal ectopic pregnancies with 73% (n = 37) and 14% (n = 7) of women receiving a single dose and repeated doses, respectively. Only 8% (n = 4) of tubal ectopic pregnancies required emergency surgery for subsequent tubal rupture. In 93% (n = 15) of cases of persistent pregnancy of unknown location, treatment was successful with one patient requiring uterine evacuation. Women with caesarean scar pregnancy were treated with combined MTX and uterine evacuation without complication. CONCLUSIONS: The efficacy of medical treatment with systemic MTX for confirmed tubal ectopic pregnancy in our hospital is in line with national and international standards. Careful consideration should be given to treating caesarean scar pregnancy and persistent pregnancy of unknown location with systemic MTX. Systemic MTX use guided by clinicians specialised in early pregnancy complications and safe medication practices may improve treatment success and reduce adverse events.