Weight gain has been reported in 11% of patients being treated with Truxima (rituximab) for non-Hodgkin’s lymphoma (NHL). Be sure to contact your doctor or 911 right away if you have a rapid or unexplained weight gain or fluid retention (edema), nausea, vomiting, diarrhea, or lack of energy when using Truxima, because you may need immediate medical care.

Tumor Lysis Syndrome (TLS) is a serious side effect that can occur with Truxima and could be a cause of weight gain (due to fluid retention). TLS can happen within 12 to 24 hours after an infusion of Truxima.

Non-Hodgkin's lymphoma (NHL) is a blood cancer that begins in your immune system. White blood cells called lymphocytes grow abnormally and can form tumor growths throughout the body. Truxima is approved by the FDA to treat certain a certain form of NHL.

Why is Truxima prescribed?

Truxima (rituximab-abbs) injection from Celltrion was the first biosimilar approved to Rituxan (rituximab) for the treatment of adults with CD20-positive, B-cell non-Hodgkin’s lymphoma (NHL), alone or with other chemotherapy medicines.

• It is now also approved, when added to other treatments, for adults with chronic lymphocytic leukemia (CLL), rheumatoid arthritis, granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA).
• It is given as an intravenous (IV) infusion. Your healthcare provider will calculate your dose.
• Common side effects, depending upon use, include: infusion reactions, fever, low level of white blood cell), chills, diarrhea, headache, infections, weakness (asthenia), upper respiratory tract infection, common cold symptoms, urinary tract infection, and bronchitis, muscle spasms, anemia, or peripheral edema, among others.

Study: Weight Gain with Truxima

In one study (NHL 6 Study) evaluating the use of Truxima in patients with Non-Hodgkin’s lymphoma, weight gain was reported more frequently in 11% of patients receiving Truxima (rituximab) following chemotherapy (first-line cyclophosphamide, vincristine, and prednisone [CVP]) compared to 4% of patients who received no further treatment.

• In NHL Study 6 a total of 322 patients with previously untreated low-grade, B-cell NHL who did not progress after 6 or 8 cycles of CVP chemotherapy were enrolled in an open-label, multicenter, randomized trial.
• Patients received either rituximab, 375 mg/m² intravenous (IV) infusion, once weekly for 4 doses every 6 months for up to 16 doses or no further therapeutic intervention.
• Results showed a reduction in the risk of cancer progression, relapse, or death (hazard ratio estimate 0.36 to 0.49) for patients randomized to rituximab as compared to those who received no additional treatment

In addition to weight gain, other side effects in this study that occurred in 5% or more of patients receiving Truxima vs. no treatment included:

• fatigue (39% vs. 14%)
• anemia (35% vs. 20%)
• weakness
• numbness, pain or tingling; usually in the hands and feet (30% vs. 18%)
• infections (19% vs. 9%)
• pulmonary toxicity (18% vs. 10%)
• liver / bile duct / gallbladder toxicity (17% vs. 7%)
• rash and/or itching (17% vs. 5%)
• joint pain (12% vs. 3%)

Why does Truxima cause weight gain?

A serious side effect called Tumor Lysis Syndrome (TLS) can occur with Truxima, and may be one reason why weight gain occurs. TLS can happen within 12 to 24 hours after an infusion of Truxima. Your doctor may give you a medicine to help prevent this problem, especially if you are higher risk.

What is Tumor Lysis Syndrome (TLS)?

Tumor Lysis Syndrome (TLS) can be life-threatening, and can occur when dying cancer cells break down quickly after treatment. The cancer cells release large amounts of substances into the blood (like potassium, phosphate, calcium, and uric acid), which can be dangerous to your organs if not treated. TLS is a problem frequently seen with cancer therapy and can be fatal if not prevented or treated.

In TLS, heart problems can cause abnormal heart rhythms or kidney problems may lead to kidney failure. It most commonly happens after chemotherapy or radiation treatment for cancer, but may also occur after other forms of treatment.

The most common cancers associated with tumor lysis syndrome (TLS) include non-Hodgkin lymphoma (30%), solid tumors (20%), acute myeloid leukemia (19%), and acute lymphocytic leukemia (13%).

Signs and symptoms of tumor lysis syndrome (TLS) include:

• fluid retention (swelling or edema), rapid weight gain, swelling / distention in face or abdomen (stomach)
• fatigue, extreme tiredness
• confusion
• nausea, vomiting
• diarrhea
• muscle weakness
• muscle cramps, or spasms
• tingling around your mouth or in your hands or feet (neuropathy)
• abnormal heart rhythm: heart fluttering, or beats faster or slower than normal
• seizures

You should seek immediate medical care or call 911 if you have: a seizure, heart palpitations, repeated vomiting, the feeling of pins and needles in mouth, hands or feet, muscle weakness or cramps, confusion, blood in your urine, you are urinating less than normal or not at all.

Follow your doctor's instructions exactly when be treated with Truxima. If you have questions or concerns about side effects, ask your healthcare provider. Be sure to read the FDA-approved patient labeling (Medication Guide).

This is not all the information you need to know about Truxima (rituximab-abbs) for safe and effective use and does not take the place of your doctor’s directions. Review the full product information and discuss this information and any questions you have with your doctor or other health care provider.