This article looks at the side effects of Rituxan. Rituxan, the anti-CD20 monoclonal antibody developed by Genentech, is arguably one of the top two or three most important and impactful cancer drugs developed in the last several decades. The biological therapy has dramatically boosted the survival times for many hundreds of thousands of patients with various forms of non-Hodgkin's lymphoma.
But this therapy is still a baby, only recently approved by the FDA in 1997. Despite many successes with this treatment, the medical community is still learning many things about how it works and the many negative side effects of Rituxan that have been or are still being reported to the FDA.
The following discussion of some of the potential side effects of Rituxan is not comprehensive, not by a wide mile. If patients feel their doctor has not adequately discussed the risks, they are urged to take a closer look at the drug's full prescribing instructions, available at Rituxan.com as well as from their local pharmacist.
Infusion reactions are reactions experienced within 30 to 120 minutes of receiving Rituxan, and tend to get resolved by the attending health care professionals rather quickly. The most common side effects of Rituxan are:
- Fever / chills / rigors
- Nausea and/or Vomiting
- Pruritus or rash
- Angioedema
- Hypotension or Hypertension
- Headache
- Bronchospasm
- Urticaria
- Myalgia
- Dizziness
TLS is one of the potentially serious side effects of Rituxan that can occur between 12-24 hours following infusion. What happens is this: Rituxan is in the body, doing its job of killing cancer cells. Unfortunately, when a cancer cell is killed, it comes apart and all its contents are spilled into the blood, where this can upset the chemical balance and cause organ damage. The most serious manifestations of TLS are:
- Acute kidney failure
- Hyperkalemia (too much potassium in the blood)
- Hypocalcemia (too little calcium in the blood)
- Hyperuricemia (a build-up of uric acid in the blood)
- Hyperphosphatemia (too much phosphorus in the blood)
A mucocutaneous reaction is one in which the skin is overtaken by rashes, bullae, and general necrosis.
- Paraneoplastic pemphigus (a blistering disease)
- Stevens-Johnson syndrome (life-threatening skin condition)
- Lichenoid dermatitis (allergic condition representing many skin disorders)
- Vesiculobullous dermatitis (allergic condition representing many skin disorders)
- Toxic epidermal necrolysis (life-threatening skin condition)
These are extremely rare. If they occur, their onset is anywhere between 1 and 13 weeks following infusion.
PML is one of the rarest—and scariest—potential side effects of Rituxan. I remember when the Cochrane Collaboration reported on this a couple years ago. PML is a fatal brain virus that has been associated with Rituxan (and one or two other monoclonal antibodies). Patients exhibit symptoms that resemble Alzheimer's and die within months. It is extraordinarily rare, but it can happen, generally within 12 months of the last infusion.
Because Rituxan kills B-lymphocytes, patients are often immunocompromised and therefore more susceptible to infection. These infections can occur up to a year following the last infusion and include viral reactivation of a dormant virus in the body, such as:
- Hepatitis B
- Hepatitis C
- Cytomegalovirus
- Herpes simplex virus
- Parvovirus B19
- Varicella zoster virus
- West Nile virus
Or it can involve other bacterial or fungal infections.
According to clinical trial data, adverse reactions in patients receiving Rituxan for NHLs include the following, which were found to occur up to 12 months after Rituxan infusion:
Systemic reactions
More common: Fever, chills, infections, asthenia
Less common: headaches, abdominal pain, back pain
Lymphatic system reactions
More common: Lymphopenia
Less common: Leukopenia, neutropenia, thrombocytopenia
Skin/appendage reactions
More common: Night sweats, rash, pruritus
Respiratory reactions:
More common: Increased cough, rhinitis
Less common: Bronchospasm, dyspnea
In this case, reports of the so-called "Rituxan cough" seems to be on the rise, and it is one of the side effects of Rituxan worth watching out for.
Metabolic and nutritional disorders:
Less common: Angiodema, hyperglycemia, peripheral edema, LDH increase
Digestive system reactions:
Nausea, and to a lesser extent, diarrhea and vomiting
There were also small percentages of reports of people experiencing nervous system reactions, musculoskeletal reactions, and cardiovascular system reactions.
Full Prescribing Information for Rituxan (opens as PDF file)
Bonander, Ross. CancerTreatment.net, Rituxan