Ribociclib and Renal Stones
Ribociclib does not cause renal stones. There is no evidence in the medical literature, FDA labeling, or clinical trial data linking ribociclib to nephrolithiasis or renal stone formation.
Evidence from Clinical Trials and Safety Data
The major clinical trials evaluating ribociclib (MONALEESA-2, -3, and -7, plus NATALEE) have not reported renal stones as an adverse event at any grade 1. The known renal adverse effects of ribociclib are distinctly different:
Documented Renal Adverse Effects of Ribociclib
- Creatinine elevation is the primary renal concern, occurring in approximately 20% of patients receiving ribociclib plus letrozole, though most elevations are mild (grade 1-2) 2
- Acute kidney injury (AKI) has been reported rarely, with grade 3-4 AKI causing treatment discontinuation documented in isolated case reports but not in the pivotal trials 2
- Drug-drug interactions affecting renal function can occur, particularly with metformin in patients with preexisting renal impairment, leading to lactic acidosis rather than stone formation 3
Renal Dosing Considerations
- No dose adjustment is required for patients with mild to moderate renal impairment, as ribociclib exposure at steady state is comparable across these renal function groups 4
- A reduced dose is recommended for patients with severe renal impairment 4
- Ribociclib is eliminated primarily by hepatic metabolism (~84% of total elimination), mostly via CYP3A4, with minimal renal excretion 5
Clinical Context for Your Patient
For a patient with metastatic rectal adenocarcinoma and a history of kidney issues, ribociclib would not be an appropriate therapy regardless of renal stone concerns, as:
- Ribociclib is FDA-approved exclusively for hormone receptor-positive, HER2-negative breast cancer, not for colorectal malignancies 1
- The drug has no established role or efficacy data in gastrointestinal cancers 1
If Renal Stones Develop During Cancer Treatment
If your patient develops renal stones, investigate alternative causes:
- Chemotherapy-related tumor lysis syndrome
- Dehydration from chemotherapy-induced nausea/vomiting
- Metabolic abnormalities from cancer or its treatment
- Concurrent medications (not ribociclib)
- Underlying metabolic stone disease
The development of renal stones in a cancer patient should prompt evaluation for these common etiologies rather than attribution to ribociclib, which has no documented association with nephrolithiasis.