The FDA has warned patients of the risk of developing progressive multifocal leukoencephalopathy after taking the immunosuppressive drug Rituxan. Rituxan is used to treat patients who have B cell leukemia, autoimmune disorders, B cell non-Hodgkin’s lymphoma, and rheumatoid arthritis. Despite the risk of progressive multifocal leukoencephalopathy, many patients have died, or have developed chronic brain damage. The drug manufacturer Genentech has made billions of dollars in drug sales after mismarketing the drug and still produces more Rituxan capsules even after years of warnings.

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What Is Rituxan?

Rituxan is a medication immunosuppressant that is used to treat patients who have B cell leukemia, autoimmune disorders, B cell non-Hodgkin’s lymphoma, and rheumatoid arthritis. This drug is part of a class of drugs called monoclonal antibodies which are lab proteins used to fight off germs.

What Is B-Cell Leukemia?

B-cell leukemia, or chronic lymphocytic leukemia, is a cancer that lives within the blood cells in the bone marrow. In particular, B-cell leukemia affects the “B lymphocytes” that help the body fight off infections. When the cells in the bone marrow become compromised in leukemia, it can cause symptoms such as pain, fever, night sweats, weight loss, and a weakened immune system.

What Is B-Cell Non-Hodgkin’s Lymphoma?

B-cell non-Hodgkins’s lymphoma is one of the most common subtypes of lymphoma. It’s considered a cancer of the lymphatic system, where white blood cells start growing abnormally and turning into tumors. Symptoms of B-cell non-Hodgkin’s lymphoma include swelling of the neck’s lymph nodes, drastic weight loss, chest pain, and chronic fatigue.

What Are Autoimmune Disorders?

Autoimmune disorders, or autoimmune disease, is when the immune system stops protecting the body from unwanted bacteria or parasites, and instead starts attacking it. Typically, healthy cells are meant to communicate with the organs in the body to keep your immune system functioning properly. Many experts still don’t know the exact cause of autoimmune disorders, however, some medications or illnesses can cause chronic symptoms. These symptoms are typically bloating, rashes, hair loss, swelling, and ongoing pain or inflammation.

What Is Rheumatoid Arthritis?

Rheumatoid Arthritis is a disorder characterized by chronic inflammation of the joints. This inflammation is usually caused when the immune system attacks its tissues, which leads to painful swelling and sometimes erosion of the joints. Symptoms of rheumatoid arthritis include joint stiffness, tenderness, fever, or fatigue.

What Is Rituxan Made From?

Rituxan, also known as rituximab, is a highly purified amino acid antibody that is produced in mammalian cell culture. These antibodies are used to treat some types of cancer and autoimmune disorders with ingredients such as Chinese hamster ovary cells.

When Did the FDA approve Rituxan?

Rituxan was created by Genentech, a subsidiary of Roche Group. Later, it was approved on November 26, 1997, by the FDA. Currently, three other similar medications to Rituxan are available on the market that act as immunosuppressant drugs. 

What Are the Side Effects of Rituxin?

Rituxin side effects vary from person to person, but in some people, the symptoms can be long-lasting or permanent. However, evidence suggests that taking Rituxan may result in an increased risk of both progressive multifocal leukoencephalopathy and death. 

Short-term side effects of taking Rituxin include: 

  • Confusion
  • Dizziness
  • Loss of Balance

What Is Confusion?

Confusion can occur due to disruptions in brain activity. Everybody can become confused at times, however, when it becomes chronic or perhaps a state of delirium, it can be a serious medical condition. Medically advanced confusion is not a small mix-up, but instead an altered mental status that affects one’s ability to focus or remember important events.

What Causes Confusion?

There is usually not one thing that confuses, but a combination of many factors. Some instances that may cause a patient to experience confusion include: 

  • Brain bleeds
  • Alcohol intoxication
  • Brain lesions
  • Brain cancer
  • Endocrine disorders
  • Temperature disruptions
  • Stroke
  • Mental health conditions
  • Head injuries
  • Migraines
  • Infections

What Are the Symptoms of Confusion?

Medical confusion, unlike common forgetfulness, can have clear differences. Someone who has confusion may have: 

  • Memory disruptions
  • Impaired thinking
  • Disorientation
  • Hallucinations

What Is Dizziness?

Dizziness is used to describe the uneasy feeling of faintness or a sense that your vision has become blurry or body unstable. Dizziness is typically not a serious emergency, however, it may signal a lack of blood flow to the brain.

What Are the Symptoms of Dizziness?

Dizziness may often accompany a brain condition, or it could be due to a lack of nutrients such as iron. Symptoms of dizziness can include: 

  • Lightheadedness
  • Loss of balance
  • Feeling faint
  • Vertigo, or a feeling that something is spinning

What Are the Risk Factors Associated With Dizziness?

Factors that can increase the risk of or effects of dizziness include: 

  • Anxiety 
  • Anemia
  • Low blood sugar
  • Overheating
  • Dehydration

What Is Loss of Balance?

Loss of balance can occur due to a variety of reasons. It could stem from a neurological problem, joint problems, or a combination of a lack of interconnectedness between the nervous system. Lack of balance can sometimes occur in healthy people, however, consistent balance problems may signal a disconnect that should be explored.

What Are the Symptoms of Loss of Balance?

Balance loss symptoms usually encompass a combination of symptoms, similar to feeling dizzy. This can include things such as: 

  • Faintness
  • Lightheadedness
  • Vision changes
  • Confusion
  • Unsteadiness
  • Lack of sensory motion detection

What Are the Risk Factors Associated With Loss of Balance?

Factors that can increase the risk of or effects of balance loss include: 

  • Ear infection
  • Head injury
  • Medications
  • Unstable joints

Why Is Rituxan Under Scrutiny?

Rituxan is under scrutiny due to its link to a dangerous condition: progressive multifocal leukoencephalopathy, or PML. As an immunosuppressant, the treatment has been used for lymphoma patients. However, the drug has been shown to have severe side effects on the brain and central nervous system.

Additionally, many professionals feel that the dangers and potential side effects accompanying Rituxan were not represented in industry-sponsored marketing. 

What Is Progressive Multifocal Leukoencephalopathy (PML)?

Progressive multifocal leukoencephalopathy is a brain infection that can slowly lead to progressed neurological disabilities. If the root cause is not treated the infection could become severe and shorten life expectancy to only 6 to 12 months after diagnosis.

What Are the Symptoms of PML?

Common symptoms of PML include:

  •       Coma
  •       Ataxia
  •       Vision loss
  •       Mental deterioration
  •       Seizures
  •       Paralysis
  •       Disturbances in speech
  •       Facial weakness
  •       Memory failure
  •       Cognitive failure
  •       Hemiparesis

Who Is More at Risk of PML?

People who already have cancer or other progressive diseases could be at risk of developing PML. The most common illnesses or people that are at increased risk are:

  • HIV/AIDS patients
  • People who have taken immunosuppressant medicines 
  • Lymphoma patients
  • Organ donors
  • Leukemia patients

What Complications Can PML Cause?

Brain health is essential to our everyday functioning and understanding of the world. It’s interconnected to our bodies and can control everything from motor movements to decision-making. Complications from PML brain infections can include:

  • Difficulty moving
  • Mental impairment
  • Vision problems
  • Sensory deficit 
  • Loss of coordination
  • Weakness
  • Slurred speech
  • Personality changes
  • Paralysis

How Does Rituxan Cause Progressive Multifocal Leukoencephalopathy (PML)?

Rituxan has been shown to result in progressive multifocal leukoencephalopathy in patients with weakened immune systems. Since the drug suppresses a patient’s immune system, it can lead to more vulnerability to infection, especially of the brain. An infection of the brain can occur when the myelin of the brain cells targets the white matter of the brain, leading to dysfunction.

Why Are There Rituxan Lawsuits?

While the FDA approved Rituxan for use in conditions such as lymphoma, the drug manufacturers did not adequately warn patients about the severe side effects such as the development of PML. Many people reported having symptoms of the condition after taking the immunosuppressive drug, and some patients eventually died. Due to the severity of the drug’s effects and the lack of warning, patients went to court to receive compensation for the long-lasting health damage.

What Are Plaintiffs Claiming About Rituxan?

Plaintiffs have claimed that taking Rituxin has led to brain infections causing symptoms such as seizures, memory loss, paralysis, and more. Additionally, plaintiffs also claim that the company manufacturing, Genentech, Rituxan has failed to warn patients and medical professionals about the dangers of taking the prescription. 

Are There Rituxan Lawsuit Settlements?

Previously in 2011, Genentech paid a 20 million dollar settlement after claims were made that the manufacturer marketed the drug for off-label uses as well as trained sales representatives on how to avoid being caught by the FDA doing so. As of 2023, there are still pending Rituxan lawsuits, and the drug is still being used in combination with other medicines for treatments under the production of Genentech.

Are There Any Active Rituxan Lawsuits?

In the U.S. District of Court New Jersey, there are active lawsuits regarding Rituxan and similar immunosuppressive drugs as of 2023.

What Are the FDA’s Warnings About Rituxan?

In 2013, the FDA sent out a drug safety communication warning public individuals about changes to the label with a black box warning as a result of the fact that Rituxan can lead the hepatitis B virus to be reactivated in individuals who were carriers for the virus or previously had hepatitis B. Reactivation of hepatitis B can include problems such as hepatic failure, fulminant hepatitis, and death. The FDA has also warned about the possibility of PML brain infection after taking Rituxan.

Is Rituxan Still on the Market?

Despite many serious cases of PML infection and numerous lawsuits, Rituxan is still on the market and the medication has generated annual sales of approximately $2.3 billion. Additionally, other drug manufacturers have been pushing to create off-brand versions of Rituxan to put on the market as well.

Notwithstanding claims relating to this product, the drug/medical device remains approved by the U.S. FDA. 


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