Rituximab

Generic Details

Generic Name

Rituximab

Other Names

  • Rituxan
  • MabThera

Drug Class

  • Monoclonal antibody

Chemical Formula

C6412H9912N1694O1987S42

Molecular Weight

145781.3 g/mol

Mechanism of Action

  • Rituximab targets the CD20 antigen on B-lymphocytes, leading to cell lysis and depletion of B-cells.

Indications

  • Non-Hodgkin lymphoma
  • Chronic lymphocytic leukemia
  • Rheumatoid arthritis
  • Granulomatosis with polyangiitis
  • Microscopic polyangiitis

Common Dosage Forms

  • Injection
  • Infusion

Typical Dosage

  • Adult dose: 375 mg/m² intravenously weekly for 4 doses

Pediatric Dosage

  • Safety and efficacy in pediatric patients have not been established

Geriatric Dosage

  • Dose adjustments may be required based on individual patient factors

Side Effects

  • Infusion reactions
  • Nausea
  • Fatigue
  • Fever
  • Headache
  • Infections
  • Hypotension
  • Hepatitis B reactivation

Contraindications

  • Hypersensitivity to rituximab
  • Severe active infections

Pregnancy Category

  • Category C - Risk cannot be ruled out

Lactation Safety

  • Limited data available; caution advised

Drug Interactions

  • Live or live-attenuated vaccines
  • Immunosuppressants

Overdose Symptoms

  • Increased risk of infections

Antidote for Overdose

  • No specific antidote; manage symptoms and provide supportive care

Storage Conditions

  • Store in a refrigerator at 2°C to 8°C (36°F to 46°F); do not freeze

Pharmacokinetics

  • Absorption: Not applicable (administered via intravenous infusion)
  • Distribution: Widely distributed in the body, especially in the blood
  • Metabolism: Metabolized into inactive metabolites
  • Excretion: Eliminated mainly via the reticuloendothelial system

Precautions

  • Hepatitis B screening before treatment
  • Monitor for signs of infection during therapy

Warnings

  • Serious infusion reactions can occur; premedication may be needed
  • Risk of developing progressive multifocal leukoencephalopathy (PML)

Others

  • Regular monitoring of B-cell counts and CD20 levels during therapy is recommended