Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
FOLEX PFS vs AURLUMYN
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Methotrexate is a folate analog that inhibits dihydrofolate reductase (DHFR), blocking the synthesis of tetrahydrofolate and thereby interfering with DNA synthesis, repair, and cellular replication. It also exhibits immunosuppressive and anti-inflammatory effects through inhibition of purine and pyrimidine synthesis and reduction of cytokine production.
Microtubule inhibitor that binds to tubulin and disrupts microtubule dynamics, leading to mitotic arrest and apoptosis.
Neoplastic diseases: gestational choriocarcinoma, chorioadenoma destruens, hydatidiform mole, acute lymphocytic leukemia, meningeal leukemia, breast cancer, head and neck cancer, advanced mycosis fungoides, lung cancer (especially squamous cell and small cell types), advanced non-Hodgkin's lymphomas.,Psoriasis (severe, recalcitrant, disabling, not adequately responsive to other therapy),Rheumatoid arthritis (active, severe, refractory to first-line therapy),Off-label uses: ectopic pregnancy, sarcoidosis, inflammatory bowel disease (Crohn's disease), vasculitis, systemic lupus erythematosus, dermatomyositis, juvenile idiopathic arthritis, graft-versus-host disease, multiple sclerosis, polymyositis, acute graft rejection prophylaxis
Treatment of relapsed or refractory multiple myeloma,Treatment of relapsed or refractory mantle cell lymphoma
Methotrexate 30-40 mg/m2 IV once weekly or 7.5-15 mg PO once weekly as single dose or divided into 3 doses over 24 hours.
Intravenous, 6 mg/kg every 4 weeks for 6 cycles; each cycle: Days 1 and 15 of a 28-day cycle.
Terminal elimination half-life: 6-12 hours in patients with normal renal function. With impaired renal function, half-life is prolonged (up to 24-48 hours). Low-dose methotrexate (e.g., for rheumatoid arthritis) has half-life 3-10 hours. High-dose methotrexate has a triphasic elimination: alpha phase (0.75 hours), beta phase (3.5 hours), and terminal gamma phase (10-20 hours).
Terminal elimination half-life is 12-15 hours in patients with normal renal function; prolonged to 30-40 hours in severe renal impairment (Cr Cl <30 m L/min).
Methotrexate undergoes hepatic and intracellular metabolism to polyglutamated forms which are retained for prolonged periods. The primary metabolic pathway involves conversion to 7-hydroxymethotrexate by aldehyde oxidase. Renal excretion is the major route of elimination, with approximately 80-90% of the dose excreted unchanged in the urine within 24 hours. Enterohepatic recirculation occurs. Biliary excretion accounts for a minor fraction.
Primarily metabolized by CYP3A4 and to a lesser extent by CYP1A2 and CYP2C8.
Primarily renal excretion as unchanged drug; approximately 80-90% excreted unchanged in urine within 24 hours. Biliary/fecal excretion is minimal (<10%).
Primarily renal excretion of unchanged drug (60-70%) with biliary/fecal elimination accounting for 20-30%.
Approximately 50% bound to serum albumin, primarily to albumin. Binding is saturable at high doses.
Approximately 85-90% bound to serum albumin.
Volume of distribution: 0.4-0.8 L/kg (40-80 L/70 kg). Higher doses may increase Vd due to tissue binding. Distributes into third-space fluids, including pleural effusions and ascites.
0.5 L/kg, indicating distribution primarily into extracellular fluid with limited tissue penetration.
Oral: 60-70% (dose-dependent, saturable absorption). IM: 76-100% relative to IV. IV: 100%.
Oral bioavailability is 50-60% due to first-pass metabolism and incomplete absorption.
Cr Cl 30-60 m L/min: reduce dose by 30-50%; Cr Cl <30 m L/min: avoid use or use extreme caution with dose reduction >50%.
GFR ≥30 m L/min: no adjustment. GFR <30 m L/min: not recommended (no data).
Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 50%; Child-Pugh C: avoid use.
Child-Pugh A: no adjustment. Child-Pugh B or C: not recommended (no data).
Juvenile idiopathic arthritis: 10-15 mg/m2 IV/IM once weekly; leukemia maintenance: 15-30 mg/m2 PO/IM once weekly.
Not established; safety and efficacy not determined in pediatric patients.
Start at lower end of dosing range (e.g., 7.5-10 mg once weekly) due to reduced renal and hepatic function; monitor for myelosuppression and mucositis.
No specific dose adjustment; monitor renal function and hematologic toxicity more frequently.
WARNING: METHOTREXATE SHOULD BE USED ONLY BY PHYSICIANS EXPERIENCED IN ANTIMETABOLITE THERAPY. DEATHS HAVE BEEN REPORTED WITH THE USE OF METHOTREXATE IN THE TREATMENT OF MALIGNANCY, PSORIASIS, AND RHEUMATOID ARTHRITIS. PATIENTS SHOULD BE CLOSELY MONITORED FOR BONE MARROW SUPPRESSION, HEPATOTOXICITY, PULMONARY TOXICITY, AND RENAL TOXICITY. METHOTREXATE IS CONTRAINDICATED IN PREGNANCY AND LACTATION. DOSING FOR NON-NEOPLASTIC DISEASES (PSORIASIS AND RHEUMATOID ARTHRITIS) IS ONCE WEEKLY; DAILY DOSING HAS LED TO FATAL TOXICITY. ACCIDENTAL OVERDOSAGE HAS RESULTED IN FATALITIES.
None.
Bone marrow suppression: leukopenia, thrombocytopenia, anemia, pancytopenia,Hepatotoxicity: acute hepatitis, hepatic fibrosis, cirrhosis (especially with chronic use),Pulmonary toxicity: pneumonitis, interstitial alveolitis, pulmonary fibrosis,Renal toxicity: nephropathy, renal failure (due to precipitation of methotrexate and its metabolites in the renal tubules),Gastrointestinal toxicity: ulcerative stomatitis, diarrhea, hemorrhagic enteritis,Infections: increased risk of opportunistic infections (e.g., Pneumocystis jirovecii pneumonia),Dermatologic reactions: photosensitivity, Stevens-Johnson syndrome,Neurologic effects: encephalopathy, seizures, headache,Monitoring: baseline and periodic complete blood counts, liver function tests, renal function tests, chest X-ray,Methotrexate elimination is impaired in patients with renal impairment, ascites, or pleural effusions, leading to increased toxicity,Concurrent use of NSAIDs may increase methotrexate toxicity
Hematologic toxicity (neutropenia, thrombocytopenia, anemia), infection risk, peripheral neuropathy, cardiotoxicity (heart failure), embryo-fetal toxicity.
Pregnancy and lactation (FDA Pregnancy Category X),Severe renal impairment (e GFR < 30 m L/min/1.73 m²),Severe hepatic impairment (cirrhosis, active hepatitis),Alcoholism or alcoholic liver disease,Pre-existing blood dyscrasias (e.g., bone marrow hypoplasia, severe anemia, leukopenia, thrombocytopenia),Active immunodeficiency syndromes (e.g., AIDS),Hypersensitivity to methotrexate or any component of the formulation,Concurrent treatment with live vaccines,Breastfeeding
Hypersensitivity to AURLUMYN or any of its components.
Foods high in folate (e.g., dark leafy greens, beans, liver) may theoretically reduce methotrexate efficacy; however, patients are often given folic acid supplements to mitigate toxicity. Caffeine may interfere with methotrexate clearance; avoid excessive caffeine intake (e.g., >4 cups coffee/day). Grapefruit and grapefruit juice may increase methotrexate levels via CYP inhibition; avoid concurrent consumption. Alcohol consumption during methotrexate therapy significantly increases risk of hepatocellular injury and is contraindicated. Avoid folic acid-fortified foods (e.g., enriched cereals, breads) in large amounts unless supplementing under medical direction.
Avoid alcohol. No specific food interactions, but maintain a balanced diet. Take with food or milk if gastrointestinal upset occurs.
FDA Pregnancy Category X. First trimester: severe teratogenic effects including neural tube defects, craniofacial anomalies, and limb defects. Second trimester: increased risk of fetal growth restriction, oligohydramnios, and fetal loss. Third trimester: neonatal myelosuppression, immunosuppression, and acute renal failure.
First trimester: Increased risk of major congenital malformations (neural tube defects, cardiovascular anomalies) based on animal studies and limited human data. Second and third trimesters: Risk of fetal growth restriction, oligohydramnios, and preterm birth. Avoid in pregnancy unless benefit outweighs risk.
Contraindicated in breastfeeding. Methotrexate is excreted in human milk and can accumulate in neonatal tissues. M/P ratio not established but reported to be 0.08:1 in limited data.
No data on excretion in human milk; M/P ratio unknown. Due to potential for serious adverse reactions in breastfed infants, breastfeeding is not recommended during treatment and for at least 2 weeks after last dose.
Not applicable; contraindicated in pregnancy. If inadvertent exposure occurs, immediate discontinuation is advised. Folinic acid rescue may be considered in first trimester exposure.
No specific dosing adjustments established for pregnancy. Pregnancy-induced pharmacokinetic changes (increased volume of distribution, enhanced renal clearance) may reduce drug exposure; consider therapeutic drug monitoring if available.
Methotrexate (FOLEX PFS) is a folate analog antimetabolite; always confirm dose and route as intrathecal use has high risk of neurotoxicity. Leucovorin rescue is mandatory after high-dose methotrexate (typically >500 mg/m²) to prevent severe myelosuppression and mucositis. Monitor renal function closely as methotrexate is primarily renally excreted; accumulation can cause acute kidney injury. Hydration and urine alkalinization (target urine p H >7) enhance excretion and reduce nephrotoxicity. Avoid concurrent use of NSAIDs and weak acids (e.g., aspirin, penicillin) as they decrease renal clearance. Intrathecal administration carries risk of chemical arachnoiditis, seizures, and leukoencephalopathy; assess for neurotoxicity symptoms after dosing. Methotrexate can cause pneumonitis; rule out infection if new respiratory symptoms develop.
AURLUMYN is a proprietary name for auranofin, an oral gold compound used for rheumatoid arthritis. Monitor for oral ulcerations, dermatitis, and proteinuria. Renal function and CBC should be checked monthly. Avoid concurrent use with penicillamine, antimalarials, immunosuppressants, or cytotoxic drugs. Onset of action may be delayed 3-6 months.
Take methotrexate exactly as prescribed; do not change dose or frequency without consulting your doctor.,Avoid alcohol completely during treatment to reduce risk of hepatotoxicity.,Drink plenty of fluids (aim for 2-3 liters daily) to prevent kidney damage.,Notify your healthcare provider immediately if you develop mouth sores, fever, chills, sore throat, easy bruising/bleeding, shortness of breath, or yellowing of skin/eyes.,Women of childbearing potential must use effective contraception during treatment and for at least 3 months after last dose; methotrexate is teratogenic.,Do not take any over-the-counter pain relievers (especially NSAIDs like ibuprofen, naproxen) without clearance, as they increase toxicity risk.,Folic acid supplementation may be prescribed to reduce side effects; take it exactly as directed.,Avoid live vaccines while on treatment and for 3 months after discontinuation.,Limit sun exposure and use sunscreen as methotrexate may increase photosensitivity.
Take exactly as prescribed; do not adjust dose without consulting your doctor.,Report any mouth sores, skin rash, unexplained bruising, or change in urine color immediately.,Regular blood and urine tests are required to monitor for side effects.,May take 3-6 months to feel full benefit; do not stop suddenly.,Avoid alcohol as it may increase risk of liver toxicity.,Use effective contraception during treatment and for 6 months after stopping.,Do not take any other medications (including OTC) without approval from your doctor.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about FOLEX PFS vs AURLUMYN, answered by our medical review team.
FOLEX PFS is a Antineoplastic Agent that works by Methotrexate is a folate analog that inhibits dihydrofolate reductase (DHFR), blocking the synthesis of tetrahydrofolate and thereby interfering with DNA synthesis, repair, and cellular replication. It also exhibits immunosuppressive and anti-inflammatory effects through inhibition of purine and pyrimidine synthesis and reduction of cytokine production.. AURLUMYN is a Antineoplastic Agent that works by Microtubule inhibitor that binds to tubulin and disrupts microtubule dynamics, leading to mitotic arrest and apoptosis.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between FOLEX PFS and AURLUMYN depend on the specific clinical indication. These are both Antineoplastic Agent agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of FOLEX PFS is: Methotrexate 30-40 mg/m2 IV once weekly or 7.5-15 mg PO once weekly as single dose or divided into 3 doses over 24 hours.. The standard adult dose of AURLUMYN is: Intravenous, 6 mg/kg every 4 weeks for 6 cycles; each cycle: Days 1 and 15 of a 28-day cycle.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between FOLEX PFS and AURLUMYN in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. FOLEX PFS is classified as Category C. FDA Pregnancy Category X. First trimester: severe teratogenic effects including neural tube defects, craniofacial anomalies, and limb defects. Second trimester: increased risk of f. AURLUMYN is classified as Category C. First trimester: Increased risk of major congenital malformations (neural tube defects, cardiovascular anomalies) based on animal studies and limited human data. Second and third t. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.