by Dr. C.H. Weaver M.D. updated 3/2021
Rituxan is a drug that is used to treat rheumatoid arthritis (RA), non-Hodgkin’s lymphoma, chronic lymphocytic leukemia, and other conditions. It targets a type of white blood cell known as a B-cell. B-cells are believed to contribute to the symptoms and joint damage of RA.
Rituxan is effectively used in the management of RA and appears well tolerated and to be particularly effective in RA associated lung disease.
Rituxan is Non-Inferior to TNF Inhibitors in Early RA Patients
The results of a clinical study have demonstrated that both Rituxan® (rituximab) and tumour necrosis factor inhibitors (TNFi) are equally and highly effective for the treatment of early, active rheumatoid arthritis (RA).
Currently, most physicians use a TNFi as initial biologic treatment following failure of methotrexate. Rituxan is commonly used in the management of RA later in the disease course and the current study examined whether or not Rituxan would be clinically non-inferior and less expensive compared to a TNFi.
A 12 month clinical trial directly compared 295 active RA patients, enrolled over a 4 year period. Patients received either Rituxan or Humira® (adalimumab), a widely utilized TNFi. The 12 month changes in disease activity score were similar for both treatments, however serious adverse events were slightly higher in the Rituxan group (n=37) compared to patients receiving TNFi (n=26).
Rituxan was significantly less expensive than the TNFi and the results of the study suggest that in addition to being less costly, Rituxan offers patients with RA another treatment option early in their disease course. When considering the differences among RA patients, having another option provided both patients and their physicians with increased flexibility in their management.
In patients with RA treated with rituximab for up to 5 years, the rates of significant infections were stable over time and higher in patients who received long-term systemic steroid treatment. This article is protected by copyright.
To evaluate the safety of long-term use of Rituxan for RA, researchers collected information about more than 3,000 patients who had been treated with a combination of Rituxan and methotrexate for up to 9.5 years. Information was also collected about roughly 800 patients who had been treated with a placebo plus methotrexate.
- The rate of serious side effects remained fairly stable over time among patients treated with Rituxan. Furthermore, the rate of serious infections was similar among patients treated with Rituxan plus methotrexate (3.94 events per 100 patients per year) and patients treated with placebo plus methotrexate (3.79 events per 100 patients per year).
- Rates of heart attack and stroke were similar to rates among RA patients in the general population.
These results suggest that frequency of side effects remains generally stable over time among patients who received prolonged treatment with Rituxan. Long-term follow-up did not identify new or increasing risks of treatment.
Rituxan Safety in anti-TNF Refractory RA
The SUNSTONE [Study of the Safety of Rituxan in Patients with Rheumatoid Arthritis After an Inadequate Response to Previous Anti‐TNF Therapy] clinical study evaluated the long‐term safety of Rituxan in RA previously exposed to anti–tumor necrosis factor inhibitors (TNFi) and showed a stable, but high, rate of serious infections, opportunistic infections and an overall higher mortality rate.
The SUNSTONE was a 5-year prospective, observational study, of RA patients receiving Rituxan. A total of 989 patients were evaluated and the frequency of significant infections was 19.9%. The incidence of significant infections did not increase with time or with cumulative rituximab exposure.
The serious infection (SIE) rate was 7.60 per 100 patient‐years and is notable for being twice as high as was reported in the pre TNFi biologic therapy era and in patients not having failed multiple DMARDS and at least one TNFi.
The study authors concluded that In patients with RA treated with rituximab for up to 5 years, the rates of significant infections were stable over time and higher in patients who received long-term systemic steroid treatment. This article is protected by copyright.3
- van Vollenhoven RF, Emery P, Bingham CO 3rd et al. Long-term safety of rituximab in rheumatoid arthritis: 9.5-year follow-up of the global clinical trial programme with a focus on adverse events of interest in RA patients. Annals of the Rheumatic Diseases. 2013 Sep 1;72(9):1496-502.
- Porter D, van Melckebeke J, Dale J, Messow C, et al. Tumour necrosis factor inhibition versus rituximab for patients with rheumatoid arthritis who require biological treatment (ORBIT): an open-label, randomised controlled, non-inferiority, trial. The Lancet. Volume 388, No. 10041, p239–247, 16 July 2016.