An in vitro, light responsive, retinal model for accurate predictions of in vivo outcomes you can have confidence in.
aProximate™ platform: The most advanced near-physiological high throughput kidney proximal tubule cells (PTC) model is available from a range of species to allow cross species comparison and in vitro-in vivo extrapolation (IVIVE) to improve clinical outcomes predictions in humans.
Validated model: The aProximate™ platform is validated for a range of species allowing direct cross species comparison of drug transport pathways. The use of such a reliable in vitro tool helps de-risk drug discovery.
Drug handling in different species
Cross-species drug handling and transport assays are performed on mouse knock-out (KO) model or other preclinical species. However due to species differences, those models are not always as predictive of human responses as expected. A more detailed understanding of how new drugs are transported and eliminated through the kidney at the transporter level in the chosen preclinical models is paramount to mitigating the risk of renal toxicity in humans. To this end robust comparative in vitro models, such as the aProximate™ platform, are needed to improve vitro-in vivo extrapolation (IVIVE).
Case study: Cross species comparison of PAH excretion
Para-aminohippurate (PAH), a derivative of hippuric acid, is used as a diagnostic agent for the measurement of renal plasma flow. When infused intravenously (IV), PAH is largely extracted from the blood by OAT1, the classic PAH transporter. Addition of probenecid, an OAT1 inhibitor, reduces PAH clearance due to drug-drug interactions at the transporter level.
Handling of PAH
Handling of PAH is known to be different in different preclinical species with a net excretion of PAH in humans and rats compared to a net absorption in dogs. PAH excretion was evaluated in vitro using aProximate™ PCTs from 4 different species to determine if the differences in PAH handling could be detected in vitro.
Cross species differences (Human, dog, rat)
The cross species difference in PAH drug handling observed in vivo was confirmed in vitro by comparing PAH flux data in human, rat and dog aProximate™ PTCs in the absence and presence of probenecid, which reduces OAT1 transport. Measure of PAH apical to basolateral flux (JAB), basolateral to apical flux (JBA) and net flux (JNet) showed a net secretion of PAH in human, non-human primates, and rat aProximate™ PTCs and a net absorption in dogs. In summary, aProximate™ is an ideal model to test drug handling and drug safety in different species in vitro prior to selecting preclinical species. The ability to reliably predict drug transport mechanisms contributes to the Nc3R (National Centre for replacement, refinement, and reduction of animals in research) goals, aiming to reduce animal studies for investigational studies of the kidney.
Newcells aProximate™ platform: De-risk your drug discovery pipeline
Accelerate your research with a reliable and consistent supply of proximal tubule cells validated for drug safety & efficacy as well and drug transporter assays. The highly predictive platform provides detailed mechanistic insights into drug handling.
Using in vitro aProximate™ platform accelerates and de-risk drug discovery and reduces the requirement for animal experiments for investigational studies of the kidney.
aProximate™ The most advanced near-physiological high throughput kidney proximal tubule cell (PTC) model.
Recapitulates Proximal tubule physiology
- Expression of all key renal transporters
- High throughput solution for industry
- Outperforms competitor in vitro models
- FDA approved kidney biomarkers
- Enables mitochondrial health monitoring
Have any questions? Check out our Frequently Asked Questions.
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Predictive in vitro primary proximal tubule models for understanding nephrotoxicity in drug develppment programs. Brown C., March 2020, Webinar
Reducing compound attrition by predicting renal tubular toxicity with in vitro PTEC models. Brown C., Sept 2020, Webinar