Yes, carboplatin, pemetrexed, and pembrolizumab can all cause acute kidney injury, both individually and in combination, with the risk increasing when all three agents are used together.
Individual Nephrotoxic Mechanisms
Each component of this regimen carries distinct renal toxicity risks:
Carboplatin has limited nephrotoxic potential compared to cisplatin, but the FDA label explicitly warns that concomitant treatment with other nephrotoxic agents increases renal toxicity 1. It can cause acute tubular injury.
Pemetrexed is clearly nephrotoxic, causing acute tubular injury and acute tubular necrosis as its primary mechanism 2. The KDIGO guidelines specifically list pemetrexed among common anticancer drugs associated with acute kidney injury, noting it can also cause proximal tubulopathy, Fanconi syndrome, and nephrogenic diabetes insipidus 2.
Pembrolizumab causes immune-mediated acute kidney injury, primarily through acute tubulointerstitial nephritis 2, 3. The FDA label documents acute kidney injury occurring in 21% of patients receiving pembrolizumab with lenvatinib, with 5% experiencing grade 3-4 toxicity 4. ASCO guidelines report AKI incidence of 1-2% with pembrolizumab monotherapy, but emerging data suggest rates of 9.9-29% when including all stages of AKI 3.
Combination Therapy Risks
The combination significantly amplifies kidney injury risk. In the KEYNOTE-021 trial, acute kidney injury occurred in 3% of patients receiving pembrolizumab plus carboplatin/pemetrexed (grade 3 or worse) 5. More recent real-world data shows the highest rate of early AKI (16.7%) occurs specifically with the pemetrexed/pembrolizumab/carboplatin combination 6.
A critical 2024 case report demonstrates how these agents can mask each other's nephrotoxicity: a patient developed kidney injury that initially appeared to be pemetrexed-induced chronic tubulointerstitial damage, but after pemetrexed discontinuation, the injury worsened, revealing underlying pembrolizumab-induced acute tubulointerstitial nephritis 7. This highlights that concurrent drug-induced nephrotoxicity must be considered when combining immune checkpoint inhibitors with chemotherapy.
Clinical Implications and Monitoring
Early AKI (within 21 days of the fourth cycle) is associated with significantly reduced 12-month survival (HR 1.733,95% CI 1.060-2.835) 6. The median time to onset for pembrolizumab-induced AKI is 91 days (range 21-245 days) 3.
Key Risk Factors:
- Total number of pemetrexed cycles ≥10 (OR 7.94) 8
- Concomitant use of NSAIDs, ACEIs/ARBs, or diuretics (OR 6.30) 8
- Prior platinum therapy
- Baseline renal impairment 1
Monitoring Protocol:
- Check serum creatinine before every dose of pembrolizumab 3
- Monitor for proteinuria (>1 g/day warrants kidney biopsy consideration) 2
- Evaluate other causes when creatinine rises: IV contrast, medications, volume status 3
Management Algorithm
For Grade 1 toxicity: Resume routine creatinine monitoring if improved to baseline 3.
For Grade 2 toxicity: Hold therapy. If improved to grade 1, taper corticosteroids over ≥3 weeks before resuming treatment. If elevations persist >7 days or worsen, treat as grade 3 3.
For Grade 3-4 toxicity:
- Permanently discontinue pembrolizumab 3
- Consult nephrology immediately 3
- Administer corticosteroids (1-2 mg/kg/day prednisone equivalent) 3
- Consider kidney biopsy to distinguish between pemetrexed-induced tubular injury versus pembrolizumab-induced tubulointerstitial nephritis 7, 9
- If no improvement after 3-5 days (grade 3) or 2-3 days (grade 4), add additional immunosuppression such as mycophenolate 3
Common pitfall: Assuming kidney injury is solely from one agent and continuing the others. The case series demonstrates that pathologic findings can be mixed or sequential, requiring biopsy for definitive diagnosis when injury persists or worsens despite discontinuing the presumed offending agent 7, 9.