# Tubular secretion, kidney disease progression, and drug dosing in older adults

> **NIH NIH K23** · UNIVERSITY OF CALIFORNIA, SAN DIEGO · 2020 · $200,666

## Abstract

PROJECT SUMMARY
This is a second submission of a K23 application by Pranav Garimella, MD, MPH a nephrologist at the
University of California San Diego (UCSD). The proposal will establish Dr. Garimella as an independent
investigator in kidney tubule secretion. This project will rigorously evaluate how markers of tubular secretion
are associated with kidney histology, kidney function decline and drug clearance.
Candidate: The objective of this application is to support Dr. Garimella's career development into an
independent investigator and international leader in tubular secretion. Dr. Garimella's training objectives
through the K23 are; 1) to learn the design and implementation of pharmacokinetic (PK) studies; 2) to become
proficient at novel biomarkers methodology and translation to patient oriented research; 3) to gain expertise in
advanced statistical methods for biomarker analyses;) to evaluate how biomarkers are associated with
histology and clinical outcomes; and 5) to develop an independent research program. He has assembled a
multidisciplinary mentorship team comprised of a primary mentor, Dr. Joachim Ix, a renowned expert on
tubular aspects of kidney disease diagnosis and prognostication, and the following additional co-mentors and
advisors: Dr. Mark Sarnak, an authority on the non-glomerular kidney function in the elderly, Dr. Edmund
Capparelli a leader in PK studies and modelling; and Dr. Florin Vaida, an applied statistician who directs the
UCSD CREST biostatistics program and has expertise in biomarkers, cohort studies and pharmacometrics.
Research: Tubulointerstitial fibrosis (TIF) is common on biopsy, predicts kidney failure and is often present in
older adults despite seemingly normal creatinine values. TIF may result in the loss of important tubular
functions such as secretion which is the predominant mode of elimination of a number of drugs. Dr. Garimella's
overall hypothesis is that measurement of novel endogenous markers of secretion may improve our
understanding of TIF which is currently only assessed on biopsy, improve our ability to identify those at risk of
kidney disease progression, and improve our ability to more appropriately dose secreted medications. In Aim
1, he will identify endogenous markers of tubular secretion which are strongly associated TIF among 200
patients who have undergone native kidney biopsies. In Aim 2, he will perform a case control study to
determine whether endogenous secretion markers predict loss of kidney function in community-dwelling older
adults. Aim 3 will provide an important proof-of-concept study, dovetailing extensively with his planned training
in PK/PD and clinical pharmacology, in which Dr. Garimella will perform a PK study to determine whether the
same secretion markers identified in Aims 1 and 2 also predict clearance of penicillin; a highly secreted drug.
This research will lay the groundwork for the further studies in clinical pharmacology (to be proposed in an R01
at the end of t...

## Key facts

- **NIH application ID:** 9926239
- **Project number:** 5K23DK114556-03
- **Recipient organization:** UNIVERSITY OF CALIFORNIA, SAN DIEGO
- **Principal Investigator:** Pranav Garimella
- **Activity code:** K23 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $200,666
- **Award type:** 5
- **Project period:** 2018-07-01 → 2023-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9926239

## Citation

> US National Institutes of Health, RePORTER application 9926239, Tubular secretion, kidney disease progression, and drug dosing in older adults (5K23DK114556-03). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9926239. Licensed CC0.

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