From the Guidelines
When taking ribociclib and letrozole combination therapy, patients should monitor for signs of liver problems, heart rhythm abnormalities, and bone marrow suppression, and follow a strict schedule of blood tests and medication intake to minimize the risk of adverse effects, as recommended by the most recent guidelines 1. The combination of ribociclib and letrozole has been shown to improve progression-free survival (PFS) in postmenopausal women with HR-positive, HER2-negative recurrent or metastatic breast cancer, with a median PFS of 25.3 months compared to 16.0 months with letrozole alone 1. Key precautions for patients taking this combination therapy include:
- Monitoring for signs of liver problems, such as yellowing of skin/eyes, dark urine, and abdominal pain
- Watching for heart rhythm abnormalities
- Reporting any fever over 100.4°F immediately, as this could indicate infection due to lowered white blood cell counts
- Completing all blood tests as scheduled, typically every two weeks for the first two cycles, then monthly
- Taking ribociclib once daily for 21 days followed by a 7-day break, while letrozole is taken daily without interruption
- Avoiding grapefruit products, which can increase drug levels
- Using effective contraception during treatment and for at least 3 weeks after stopping, as these medications can harm a developing fetus
- Keeping all follow-up appointments to monitor for side effects, as early detection allows for dose adjustments or supportive care to manage complications effectively, as supported by the NCCN guidelines 1.
From the FDA Drug Label
Advise the patient to read the FDA-approved patient labeling (Patient Information) Interstitial Lung Disease/Pneumonitis Advise patients to immediately report new or worsening respiratory symptoms Severe Cutaneous Adverse Reactions Inform patients of the signs and symptoms of severe cutaneous adverse reactions QT Prolongation Inform patients of the signs and symptoms of QT prolongation Hepatobiliary Toxicity Inform patients of the signs and symptoms of hepatobiliary toxicity Neutropenia Advise patients of the possibility of developing neutropenia and to immediately contact their healthcare provider should they develop a fever, particularly in association with any suggestion of infection Embryo-Fetal Toxicity Advise pregnant women and females of reproductive potential of the potential risk to a fetus Lactation Advise lactating women not to breastfeed during treatment with KISQALI and for at least 3 weeks after the last dose Drug Interactions Inform patients to avoid strong CYP3A inhibitors, strong CYP3A inducers, and drugs known to prolong the QT interval Dosing Instruct patients to take the doses of KISQALI at approximately the same time every day and to swallow whole
The basic precautions for patients taking Ribociclib (Kisqali) include:
- Reporting new or worsening respiratory symptoms
- Being aware of the signs and symptoms of severe cutaneous adverse reactions
- Monitoring for QT prolongation
- Being aware of the signs and symptoms of hepatobiliary toxicity
- Monitoring for neutropenia
- Avoiding pregnancy and breastfeeding
- Avoiding certain drug interactions
- Following the prescribed dosing instructions 2 2
From the Research
Basic Precautions for Patients Taking Ribociclib (Kisqali) and Letrozole (Femara) Combination Therapy
- Patients should be aware of the potential for neutropenia, a common side effect of ribociclib, which can increase the risk of infection 3, 4, 5.
- Regular monitoring of blood counts and liver function is recommended to minimize the risk of adverse events 4, 6.
- Patients should be advised to report any signs of infection, such as fever or chills, to their healthcare provider promptly 4, 5.
- Dose reduction or interruption may be necessary to manage adverse events, such as neutropenia or elevated liver enzymes 4, 6.
- Patients with pre-existing kidney disease should be closely monitored for signs of acute kidney injury, as ribociclib has been associated with this adverse event 7.
- Healthcare providers should consider the potential for drug interactions and adjust the dose of ribociclib or other medications as needed 6.
Managing Adverse Events
- Neutropenia is a common adverse event associated with ribociclib, and patients should be monitored regularly for signs of infection 3, 4, 5.
- Elevated liver enzymes and acute kidney injury are potential adverse events that require close monitoring and prompt management 4, 7, 6.
- Patients experiencing adverse events should be advised to contact their healthcare provider promptly to determine the best course of action 4, 5.
Dose Modification and Management
- Dose reduction or interruption may be necessary to manage adverse events, such as neutropenia or elevated liver enzymes 4, 6.
- Patients with pre-existing kidney disease may require closer monitoring and dose adjustment to minimize the risk of acute kidney injury 7.
- Healthcare providers should consider the potential for drug interactions and adjust the dose of ribociclib or other medications as needed 6.