From the Guidelines
Kisqali (ribociclib) can cause several adverse effects, including QT interval prolongation, severe liver problems, and low white blood cell counts (neutropenia), with the most recent and highest quality study 1 reporting neutropenia in 43.8% of patients and liver-related AEs in 8.3% of patients.
Adverse Effects of Kisqali (Ribociclib)
The adverse effects of Kisqali (ribociclib) can be categorized into serious and common side effects.
- Serious side effects include:
- QT interval prolongation, which can cause abnormal heart rhythms
- Severe liver problems
- Low white blood cell counts (neutropenia)
- Common side effects include:
- Fatigue
- Nausea
- Diarrhea
- Vomiting
- Hair loss
- Headache
- Constipation
- Rash
- Decreased appetite
- Abdominal pain
- Abnormal liver function tests
Blood Disorders and Infections
Blood disorders are frequent, with anemia and low platelet counts occurring alongside neutropenia, as reported in the study 1.
- Respiratory infections and urinary tract infections may occur more frequently while taking this medication.
Monitoring and Management
Patients should be monitored regularly with blood tests and ECGs, especially during the first few cycles of treatment, as recommended by the study 1.
- Dose adjustments or temporary discontinuation may be necessary if severe side effects develop.
- Ribociclib works by inhibiting cyclin-dependent kinases 4 and 6 (CDK4/6), which regulate cell division, explaining why bone marrow suppression and other proliferation-related side effects occur.
Patient Reporting
Patients should report any unusual symptoms to their healthcare provider immediately, particularly severe fatigue, yellowing of skin/eyes, dark urine, or signs of infection like fever, as these may indicate serious adverse effects. The most recent study 1 provides the highest quality evidence for the adverse effects of Kisqali (ribociclib), and its findings should be prioritized in clinical practice.
From the FDA Drug Label
KISQALI may cause serious side effects, including: The most common side effects of KISQALI in people with early breast cancer include: • decreased white blood cell counts • decreased red blood cell counts • increased liver function tests • infections • increased kidney function test • decreased platelet counts • nausea • headache • tiredness The most common side effects of KISQALI in people with advanced or metastatic breast cancer include: • decreased white blood cell counts • decreased red blood cell counts • increased liver function tests • infections • nausea • increased kidney function test • tiredness • decreased platelet counts • diarrhea • vomiting • headache • constipation • hair loss • cough • rash • back pain • low blood sugar level
The adverse effects of Kisqali (ribociclib) include decreased white blood cell counts, infections, nausea, headache, and tiredness. Kisqali may also cause decreased red blood cell counts, increased liver function tests, and decreased platelet counts. Other possible side effects include diarrhea, vomiting, constipation, hair loss, cough, rash, back pain, and low blood sugar level 2.
From the Research
Adverse Effects of Kisqali (Ribociclib)
The adverse effects of Kisqali (ribociclib) have been reported in several studies. Some of the most common adverse reactions observed in 20% or more of patients taking ribociclib include:
- Neutropenia
- Nausea
- Fatigue
- Diarrhea
- Leukopenia
- Alopecia
- Vomiting
- Constipation
- Headache
- Back pain 3
Specific Adverse Effects
In addition to the common adverse reactions, ribociclib has also been associated with:
- Liver function test abnormalities, which can be a concern for patients with pre-existing liver conditions 4
- QTc prolongation, which can be a risk for patients with cardiac morbidities or other risk factors for QTc prolongation 4
- Neutropenia, which was the most common reason for dose reduction in patients taking ribociclib 5
- Abnormal liver enzymes, which were also a common reason for dose reduction in patients taking ribociclib 5
Real-World Outcomes
Real-world studies have also reported on the adverse effects of ribociclib. For example, a study of patients with HR+/HER2- metastatic breast cancer found that:
- 56% of patients had at least one dose reduction, with neutropenia and abnormal liver enzymes being the most common reasons 5
- 11% of patients discontinued treatment due to toxicity, with no treatment-related deaths reported 5
Comparative Safety
Comparative studies have also been conducted to evaluate the safety of ribociclib versus other CDK4/6 inhibitors. For example, a study found that:
- There were no significant overall survival differences between ribociclib, abemaciclib, and palbociclib in combination with an aromatase inhibitor for patients with HR+/HER2- metastatic breast cancer 6
- The safety profiles of the three CDK4/6 inhibitors were similar, with no significant differences in adverse effects reported 6