The Facts of Rituxan

Rituxan Approved

Rituxan, the world's best-selling cancer drug, has been approved by the U.S. Food and Drug Administration to be used in combination with methotrexate to treat rheumatoid arthritis by reducing the signs and symptoms in adult patients who have moderately-to-severely active rheumatoid arthritis and have failed one or more anti-TNF drugs e.g. Enbrel (etanercept), Remicade (infliximab), or Humira (adalimumab).

The Mechanism Of Rituxan Treatment

Rituxan selectively targets CD20-positive B-cells (b-lymphocytes). Rituxan is the first treatment for rheumatoid arthritis which selectively targets the CD20-positive B-cells. Though rheumatoid arthritis has previously been considered a T-cell-mediated disease, other research has revealed that B-cells play roles in the initiation and development of rheumatoid arthritis.

Three Controlled Studies Were Basis For Rituxan Approval

The decision to approve Rituxan for rheumatoid arthritis was based on results from three randomized, double-blind, placebo-controlled studies of patients with active rheumatoid arthritis.

In REFLEX, the phase III trial, a significantly higher number of patients who received a single treatment (two infusions) of Rituxan along with methotrexate achieved clinical endpoints (ACR20, ACR50, ACR70) compared to patients taking placebo and methotrexate.

At 24 weeks Rituxan patients had significant improvement in signs and symptoms associated with rheumatoid arthritis, including pain and disability.

How Is Rituxan Administered?

Rituxan is given to the patient as two 1000 mg IV infusions separated by two weeks. It is given in combination with methotrexate. 30 minutes prior to each infusion, it has been recommended that the steroid methylprednisolone 200 mg IV be given.

The course of treatment is repeated every 6 to 9 months, according to Genentech and Biogen, the drugmakers of Rituxan.

What Is The Cost Of Rituxan Treatment?

The cost of a course of treatment with Rituxan will cost $9,088, said to be equivalent to the TNF blocker drugs on an annual basis.

How Is Rituxan Different From The Other Biologic Drugs?

The currently available biologic DMARDs used to treat rheumatoid arthritis are classified as:

• Enbrel (etanercept) - anti-tumor necrosis factor or anti-TNF
• Remicade (infliximab) - anti-tumor necrosis factor or anti-TNF
• Humira (adalimumab) - anti-tumor necrosis factor or anti-TNF
• Kineret (anakinra) - targets interleukin-1 or IL1
• Orencia (abatacept) - T-cell co-stimulation modulator
• Rituxan (rituximab) - targets CD20-positive B-cells

What's Next For Rituxan?

What comes next for the best-selling cancer drug which is now approved for rheumatoid arthritis as well? Rituxan is being studied for other autoimmune diseases and disorders such as:

• lupus
• lupus nephritis
• vasculitis

Related Resources

_{Sources: Genentech, FDA Approves Rituxan - The First Targeted B-Cell Therapy For Treatment Of Moderate-to-Severe Rheumatoid Arthritis 2/28/06; New York Times, Rheumatoid Arthritis Drug Approved 3/1/06.}