Kidney Week

Abstract: SA-PO156

Impact of the 2021 CKD-EPI Equation on Anticancer Drug Eligibility and Dosing in Black and Non-Black Patients

Session Information

• Onconephrology: Clinical and Research Advances - II
  November 05, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
  Abstract Time: 10:00 AM - 12:00 PM

Category: Onconephrology

• 1600 Onconephrology

Authors

• Butrovich, Morgan Alexandra, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania, United States

Morgan Alexandra Butrovich,

• Qin, Jiyue, Albert Einstein College of Medicine, Bronx, New York, United States

Jiyue Qin,

• Xue, Xiaonan, Albert Einstein College of Medicine, Bronx, New York, United States

Xiaonan Xue,

• Ivy, S. Percy, National Cancer Institute, Bethesda, Maryland, United States

S. Percy Ivy,

• Nolin, Thomas D., University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania, United States

Thomas D. Nolin,

• Beumer, Jan Hendrik, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania, United States

Jan Hendrik Beumer,

Background

Cancer and kidney disease disproportionately impact Black patients, and kidney function is a key consideration in anticancer pharmacotherapy decision-making. In 2021, the new CKD-EPI equation that omits race was recommended to replace the 2009 CKD-EPI equation. The current study evaluated the impact of using the 2021 vs 2009 CKD-EPI equation to determine anticancer drug eligibility and dosing in Black and non-Black patients.

Methods

A retrospective analysis of patients enrolled in phase 1 CTEP-sponsored studies from 1995-2010 was performed. eGFR was calculated by the 2021 and 2009 CKD-EPI equations (eGFR₂₀₂₁ and eGFR₂₀₀₉, respectively) and converted to absolute eGFR (i.e., mL/min) by multiplying by BSA/1.73 m². Dosing simulations based on eGFR₂₀₂₁ and eGFR₂₀₀₉ were performed for ten anticancer drugs with renal eligibility or dosing cutoffs. Discordance in eligibility and dosing recommendations for eGFR₂₀₂₁ and eGFR₂₀₀₉ were compared between races by χ² test. Difference in drug eligibility based on eGFR equation was assessed by GEE logistic regression.

Results

3931 patients were included, 8.6% of whom were Black. The mean change between eGFR₂₀₂₁ and eGFR₂₀₀₉ for Black (-10.5 ml/min) and non-Black (4.1 ml/min) patients was significantly different (p<0.001). The proportion of patients with discordant recommendations did not differ between Black and non-Black patients. However, Black patients were 48% (95% CI: 14%–94%) more likely to be ineligible for cisplatin using eGFR₂₀₂₁ vs eGFR₂₀₀₉, controlling for sex, age, and BSA. Non-Black patients were 27% (95% CI: 18%–35%) less likely to be ineligible for cisplatin using eGFR₂₀₂₁ vs eGFR₂₀₀₉.

Conclusion

Although discordance rates in eligibility and dosing were similar between Black and non-Black patients, eGFR₂₀₂₁ was lower than eGFR₂₀₀₉ for Black patients, translating to Black patients being more likely than non-Black patients to be deemed ineligible for drugs when using eGFR₂₀₂₁. eGFR₂₀₂₁ is negatively biased for Black patients at lower eGFRs, where most drug eligibility and dosing cutoffs lie; this may lead to inappropriate exclusion of therapy for some Black patients. These findings highlight the importance of clinical judgement and use of confirmatory kidney function tests when prescribing anticancer agents, particularly in Black patients with low GFR.

Funding

• Other NIH Support