Automating and Miniaturizing Immunoassays

Toxicokinetics (TK) is generation of kinetic data for systemic exposure and toxicity assessment of the drug. These studies help us to estimate the observed toxicity to that dose. TK evaluation is very important in drug development phase in both regulatory and scientific perspective. There are several guidelines to conduct TK study in animals recommended by regulatory bodies (OECD). TK evaluation is useful in selection of dose, dosing form, alternative dosing route, evaluation of toxicological mechanism, and also used for the setting safe dose level in clinical phases. This TK studies also used to reduces the animal number (replacement, reduction and refinement). On the other hand, TK data are practically used for the purpose of drug discovery such as lead-optimization and candidate-selection. Email: marketing@medicilon.com.cn Web:www.medicilon.com

Miniaturizing immunoassays can deliver tremendous savings in sample volumes, animal use, and reagent consumption. Although reducing assay volumes in manual ELISA immunoassays is possible, it is tedious to carry out and challenging to maintain assay performance. Both issues may ultimately erode anticipated cost savings. In contrast, assay miniaturization on an automated platform not only delivers operational cost savings, it also promotes greater certainty by enabling more experiments and generating more data points from each sample. The study below illustrates one successful example of assay miniaturization on Gyrolab.

Case Study: Reduced Sample Volume Boosts Rodent Studies at Eli Lilly

A research group at Eli Lilly wanted to use their anti-drug antibody (ADA) acid dissociation and toxicokinetic assays in rodent studies. However, performing reliable assays on the limited sample volumes available from small animals required significant changes in both productivity and performance. What’s more, their previous attempts to convert these assays to other ELISA formats, such as electrochemiluminescence (ECL) and solid-phase extraction with acid dissociation (SPEAD), had been unsuccessful in achieving the required improvements. Converting to the Gyrolab platform resolved this dilemma. Researchers were able to reduce the sample volume (per duplicate) from 25 µL to 4 µL and shorten the time-to-result from 23 hours to just 4 hours. A notable improvement in drug tolerance was also observed. Table 1 summarizes these results.

Increasing assay transfer efficiency between collaborating groups

The smooth transfer of assays from biotherapeutic development groups to entities such as CROs and CMOs for validation, clinical sample testing, and other downstream processes are also areas where significant gains can be made. Using a shared automated technology platform such as Gyrolab greatly facilitates data analysis and interpretation among collaborating groups. The case study summarized below demonstrates the successful transfer and cross-validation of a Gyrolab pharmacokinetic (PK) assay in three countries to meet the needs of a clinical trial.

Case Study: Transfer and Cross-Validation of a Gyrolab Platform Assay across Three Different Countries on Two Continents

The Gyrolab platform was chosen for its ability to deliver fast turnaround using small sample volumes. The PK assay was first validated at the drug discovery and development company Novimmune in Switzerland before being transferred to a CRO in the U.K. for validation. This was followed by a transfer to a second CRO in the U.S. for further validation. Finally, the assay was cross-validated at all three sites.

The assay delivered a working range of 62.5–8000 ng/mL and passed the criteria for the initial validation, including intra- and interaccuracy and precision (±20% or less relative error [RE] and coefficient of variation [CV] or 25% RE and CV for lower limit of quantification [LLOQ]/upper limit of quantification [ULOQ]), matrix effects, dilutional linearity (up to 1 in 2000), lack of hook effect, short-term stability at room temperature after five freeze–thaw cycles, and long-term stability at –20 and –80°C.

Cross-validation at the three sites to assess ruggedness involved blinded tests on 30 samples at the CROs . The relative percentage difference between the reference result (Novimmune) and observed result (CRO) was better than ±25% for 87% of the samples, which surpassed the set acceptance criteria. This demonstrates the equivalence of the assay across the three sites, and therefore this assay could be relied upon to deliver the data needed in the multisite project.