RUXIENCE
Clinical safety rating
cautionComprehensive clinical and safety monograph for RUXIENCE (RUXIENCE).
Comprehensive clinical and safety monograph for RUXIENCE (RUXIENCE).
Non-Hodgkin lymphoma (NHL)Chronic lymphocytic leukemia (CLL)Rheumatoid arthritis (RA)Granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA)Pemphigus vulgaris
Ruxience (rituximab) is a monoclonal antibody that binds to CD20 antigen on B-lymphocytes, initiating complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC), leading to B-cell depletion.
| Metabolism | Rituximab is a monoclonal antibody; metabolism is via proteolytic degradation into small peptides and amino acids. No specific CYP450 enzyme involvement. |
| Excretion | Eliminated via reticuloendothelial system; no significant renal (less than 1%) or biliary/fecal excretion of intact rituximab. Target-mediated clearance via CD20 binding. Mean clearance: 0.14 L/h (initial), 0.012 L/h (after steady state). |
| Half-life | Mean terminal half-life: 18.0–22.0 days after last dose (range 7–32 days). Longer half-life with higher tumor burden and after multiple doses. Clinical context: maintains therapeutic levels for 3–6 months post-treatment. |
| Protein binding | Specifically binds to CD20 antigen on B cells; no significant plasma protein binding (albumin or others). Almost exclusively bound to target cells. |
| Volume of Distribution | Vd: 2.9–3.7 L (central compartment), 3.4–5.2 L (peripheral); approximates plasma volume (0.04–0.06 L/kg). Minimal extravascular distribution due to large molecular size. |
| Bioavailability | IV only; bioavailability 100% for IV infusion. No other routes available; subcutaneous formulation not applicable. |
| Onset of Action | IV infusion: Depletion of peripheral B cells within 24–48 hours; maximal depletion by 1–2 weeks. Time to clinical response in rheumatoid arthritis: 8–16 weeks; in NHL: 4–8 weeks. |
| Duration of Action | B cell recovery begins at 6–9 months post-therapy, with normalization by 12 months (median). Clinical effect in NHL: median progression-free survival varies by indication; in RA: sustained response up to 6–12 months after first course. |
| Molecular Weight | 144 |
375 mg/m2 intravenous infusion once weekly for 4 weeks (for non-Hodgkin lymphoma); 375 mg/m2 intravenous infusion day 1 of each cycle for 6 cycles (in combination with CHOP); 500 mg fixed dose intravenous infusion on days 1 and 15 of cycle 1, then day 1 of cycles 2-6 (in combination with fludarabine and cyclophosphamide for CLL); 1000 mg intravenous infusion on days 1 and 15 (for rheumatoid arthritis, with or without methotrexate).
| Dosage form | INJECTABLE |
| Renal impairment | No dose adjustment required for any degree of renal impairment. Ruxience has not been studied in patients with end-stage renal disease on dialysis. |
| Liver impairment | No formal studies have been conducted in patients with hepatic impairment. No dose adjustment is recommended based on limited data. |
| Pediatric use | Safety and effectiveness in pediatric patients have not been established for most indications. For pediatric patients with certain conditions (e.g., nephrotic syndrome), dosing is based on BSA: 375 mg/m2 intravenous infusion weekly for 4 doses, with premedication. |
| Geriatric use | No specific dose adjustment is recommended for elderly patients. However, monitor for infusion-related reactions, cardiac events, and infections more frequently due to age-related risk factors. Elderly patients may have slower clearance, but dose adjustments are not required based on pharmacokinetic data. |
| 1st trimester | Avoid use during first trimester; Rituximab may cause fetal B-cell depletion and adverse effects. |
| 2nd trimester | Use only if clearly needed; crosses placenta after week 16 and may cause neonatal B-cell depletion. |
| 3rd trimester | Use only if clearly needed; associated with neonatal B-cell depletion and delayed hematopoietic recovery. |
Clinical note
Comprehensive clinical and safety monograph for RUXIENCE (RUXIENCE).
| Placental transfer | Rituximab is an IgG1 monoclonal antibody that actively crosses the placenta, especially after the first trimester, with increasing transfer as pregnancy progresses. |
| Breastfeeding | Rituximab is excreted in human milk in low levels. Due to potential for adverse effects in the nursing infant, breastfeeding is not recommended during therapy and for at least 6 months after last dose. |
| Lactation Rating | L4 (Hazardous) |
| Teratogenic Risk | Rituximab is a humanized monoclonal antibody (IgG1) that crosses the placenta, with fetal levels increasing during the second and third trimesters. Exposure in the first trimester is not associated with major malformations; however, second and third trimester exposure can cause B-cell depletion and lymphopenia in the neonate. Cases of severe neonatal agranulocytosis, including neutropenia, thrombocytopenia, and anemia, have been reported. Infant vaccination with live vaccines should be delayed until B-cell recovery. Overall, use during pregnancy is not recommended unless clearly needed. |
| Fetal Monitoring | During pregnancy, monitor maternal complete blood count (CBC) with differential at baseline and monthly. Assess fetal growth and amniotic fluid volume via ultrasound if exposure occurs in second or third trimester. After delivery, monitor neonatal CBC and B-cell counts; hold live vaccines until B-cell recovery (usually within 6-12 months). |
| Fertility Effects | Rituximab may impair reproductive function. In male patients, transient oligospermia or azoospermia have been reported; fertility may be affected. In female patients, ovarian suppression or premature ovarian failure is possible, especially when used with other cytotoxic agents. Fertility preservation counseling is recommended before treatment. |
■ FDA Black Box Warning
Fatal infusion-related reactions, severe mucocutaneous reactions, progressive multifocal leukoencephalopathy (PML), and hepatitis B reactivation with fulminant hepatitis. Do not administer to patients with active hepatitis B infection.
| Serious Effects |
Known hypersensitivity to rituximab or any component of the productActive severe infections (e.g., hepatitis B, tuberculosis)
| Precautions | Infusion reactions, tumor lysis syndrome, severe mucocutaneous reactions (e.g., Stevens-Johnson syndrome), hepatitis B reactivation, PML, bowel obstruction and perforation, immunosuppression/infections, cardiac arrhythmias, renal toxicity (when used with cisplatin), and live vaccine administration risk. |
| Food/Dietary | No specific food interactions reported. Maintain adequate hydration to reduce risk of tumor lysis syndrome. Avoid grapefruit and other CYP3A4 modulators only if taking concomitant drugs metabolized by CYP3A4. |
| Clinical Pearls | Ruxience (rituximab) is a monoclonal antibody targeting CD20. Premedicate with acetaminophen, diphenhydramine, and methylprednisolone to reduce infusion reactions. Monitor for tumor lysis syndrome in high-tumor-burden patients. Hepatitis B reactivation risk requires screening and prophylaxis. Do not administer live vaccines during or after treatment until B-cell recovery. |
| Patient Advice | Inform your healthcare provider if you have any signs of infection, such as fever, chills, or sore throat. · Report any symptoms of infusion reactions, including itching, rash, difficulty breathing, or dizziness during or after infusion. · Avoid live vaccines (e.g., MMR, nasal flu, shingles) during treatment and for at least 6 months after last dose. · Use effective contraception during and for 12 months after treatment due to potential harm to fetus. · Notify your doctor if you have a history of hepatitis B, heart problems, or lung disease. · Expect that blood counts may drop; report unusual bruising, bleeding, or fatigue. |
Loading safety data…