Targeted Therapy / Oncology — Hematologic

Rituxan (rituximab)

Genentech / Roche; biosimilars available · Anti-CD20 Monoclonal Antibody

FDA Approved 1997 Intravenous (IV) infusion or subcutaneous injection Specialty Medication
Rituxan rituximab vials, Genentech Roche, anti-CD20 antibody for lymphoma CLL

What is Rituxan? Rituxan (rituximab) is an anti-CD20 monoclonal antibody that is foundational in the treatment of B-cell non-Hodgkin lymphomas, CLL, and certain autoimmune conditions. Multiple FDA-approved biosimilars are available.

About Rituxan

Brand NameRituxan
Generic / INNrituximab
Drug ClassAnti-CD20 Monoclonal Antibody
ManufacturerGenentech / Roche; biosimilars available
AdministrationIntravenous (IV) infusion or subcutaneous injection
FDA Approval1997
📦 Available as 100 mg/10 mL and 500 mg/50 mL (10 mg/mL) vials. SC (Rituxan Hycela): 1400 mg/11.7 mL. Multiple biosimilars: Truxima, Ruxience, Riabni, and others.

FDA-Approved Uses for Rituxan

Indications are based on FDA approval. Your healthcare provider determines appropriate use based on your specific diagnosis, stage, biomarker status, and overall clinical picture.

  • Non-Hodgkin lymphoma — relapsed/refractory low-grade or follicular CD20+
  • NHL — first-line follicular with chemotherapy (CVP)
  • NHL — first-line DLBCL with CHOP (R-CHOP)
  • NHL — maintenance in follicular after first-line chemo
  • CLL — with fludarabine and cyclophosphamide
  • Rheumatoid arthritis — with methotrexate (anti-TNF failure)
  • Granulomatosis with polyangiitis and microscopic polyangiitis — with glucocorticoids
  • Pemphigus vulgaris — moderate to severe
Biomarker Note: CD20 expression on tumor cells must be confirmed (virtually universally expressed in B-cell NHL). Hepatitis B surface antigen and core antibody testing is REQUIRED before rituximab (reactivation risk).

How Does Rituxan Work?

Rituximab targets CD20, a phosphoprotein expressed on normal and malignant B cells. Binding to CD20 causes cell death through complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC), and direct induction of apoptosis. CD20 is not expressed on stem cells or plasma cells, so B cell recovery can occur.

Dosage & Administration

NHL: 375 mg/m² IV on day 1 of each chemotherapy cycle, or per weekly dosing schedule. SC (Rituxan Hycela): 1400 mg for NHL, 1600 mg for CLL — fixed dose given over approximately 5 minutes. Infusion reaction premedication required for IV.

⚠️ Important

Dosing is individualized by the prescribing clinician. Never adjust your dose without consulting your healthcare provider. This information is educational only and does not replace the official prescribing information.

Warnings, Precautions & Side Effects

General Warning

BOXED WARNINGS: Fatal infusion reactions. Tumor lysis syndrome (TLS). Severe mucocutaneous reactions. Hepatitis B virus reactivation — can be fatal. Progressive multifocal leukoencephalopathy (PML) — fatal. Embryo-fetal toxicity.

⛔ Serious Warnings & Precautions
  • Fatal infusion reactions — boxed warning
  • HBV reactivation — boxed warning, screen all patients
  • PML — boxed warning, rare but fatal
  • Tumor lysis syndrome
  • Severe mucocutaneous reactions
  • Embryo-fetal toxicity

Common Side Effects

  • Infusion reactions (very common — first infusion)
  • Fatigue
  • Nausea
  • Fever
  • Lymphopenia
  • Infections
  • Headache

This is not a complete list. Always report new or worsening symptoms to your healthcare provider promptly.

Storage & Handling

Refrigerate at 2°C to 8°C (36°F to 46°F). Do not freeze. Protect from light.

BiologicHealthPlus provides temperature-monitored cold-chain specialty delivery for medications requiring refrigeration. Never use a medication if its storage conditions have been compromised.

Insurance Coverage, Prior Authorization & Patient Assistance

🛡️ Commercial Insurance

Rituxan is covered by most major commercial insurance plans when medically necessary and prior authorized. Coverage tier and cost-sharing vary by plan.

✅ Prior Authorization

Prior authorization is required by virtually all insurance plans for Rituxan. BiologicHealthPlus handles the complete prior authorization process at no cost to patients or providers.

🏥 Medicare Coverage

Medicare Part B covers this IV medication when administered in a clinical setting. Medicaid coverage varies by state.

🆓 Patient Assistance

Manufacturer patient assistance programs may be available for eligible uninsured or underinsured patients. Contact BiologicHealthPlus for a confidential eligibility review.

Prior Authorization Patient Assistance Insurance & Savings Medication Costs

Frequently Asked Questions — Rituxan

Rituxan was the first monoclonal antibody approved for cancer. It targets CD20 on B cells, destroying malignant B cells in lymphomas and CLL. It is also used in autoimmune diseases (RA, vasculitis, pemphigus).

Yes. FDA-approved rituximab biosimilars include Truxima, Ruxience, and Riabni. They are considered highly similar to Rituxan and are used interchangeably per formulary.

Rituximab can reactivate latent hepatitis B virus (HBV) by depleting B cells that suppress HBV — potentially causing fulminant hepatitis. HBsAg and anti-HBc testing is required before rituximab; HBV-positive patients require antiviral prophylaxis.

Rituxan IV is covered by Medicare Part B. Biosimilars may be preferred on some formularies. Prior authorization required.

Related Medications

Gazyva (obinutuzumab)  ·  Velcade (bortezomib)  ·  Revlimid (lenalidomide)  ·  Yescarta (CAR-T — after rituximab failure)

Related Conditions

Diffuse large B-cell lymphoma (DLBCL)  ·  Follicular lymphoma  ·  CLL  ·  Rheumatoid arthritis  ·  Granulomatosis with polyangiitis

Comparisons

Daratumumab Brentuximab Vedotin

Authoritative References

Medical Disclaimer: This page is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult your oncologist, hematologist, or licensed healthcare professional before making any treatment decisions. Last reviewed: August 2026 by the BiologicHealthPlus Clinical Team.