Is Enhertu Nephrotoxic?
Enhertu (trastuzumab deruxtecan) is not considered nephrotoxic and does not require dose adjustment in patients with mild to moderate renal impairment. 1
Renal Safety Profile
The FDA label explicitly addresses renal considerations for Enhertu:
No dose adjustment required for patients with:
- Mild renal impairment (creatinine clearance 60-89 mL/min)
- Moderate renal impairment (creatinine clearance 30-59 mL/min) 1
Important caveat: Patients with moderate renal impairment have shown a higher incidence of Grade 1 and 2 interstitial lung disease (ILD)/pneumonitis, requiring more frequent monitoring 1
The recommended dosage has not been established for severe renal impairment (creatinine clearance <30 mL/min) 1
Context Within HER2-Targeted Therapies
While some anticancer agents targeting HER2 and EGFR can cause renal toxicity—particularly when combined with traditional chemotherapy 2—trastuzumab deruxtecan specifically does not demonstrate direct nephrotoxic effects. The broader KDIGO guidelines on onco-nephrology identify various targeted cancer agents that cause kidney injury (including tyrosine kinase inhibitors causing tubulointerstitial injury and anti-angiogenesis drugs causing proteinuria and thrombotic microangiopathy) 3, but trastuzumab deruxtecan is not among the agents flagged for renal toxicity.
Primary Toxicity Concerns
The dominant safety concern with Enhertu is ILD/pneumonitis (occurring in 10-15% of patients, with rare fatal cases), not nephrotoxicity 4, 5. Other common adverse events include:
- Gastrointestinal effects
- Hematologic toxicity (neutropenia in ~9% at grade ≥3) 5
- Musculoskeletal symptoms 6
Clinical Monitoring Recommendations
For patients with moderate renal impairment receiving Enhertu:
- Monitor more frequently for ILD/pneumonitis symptoms (dyspnea, cough, fever)
- Standard renal function monitoring is appropriate
- No specific nephrotoxicity surveillance protocols are required beyond routine care
Kidney impairment should not be considered a contraindication to Enhertu therapy in patients with mild to moderate dysfunction, as the drug does not demonstrate direct renal toxicity 1, 2.