Anti-SN-38 payload antibody in PK study in ADC drug development

Anti-SN-38 antibodies are particularly used in pharmacokinetic (PK) investigations to quantify the SN-38 and its conjugates’ concentrations in biological matrices. SN-38 is the active metabolite of irinotecan which is a chemotherapeutic agent used mainly for treating colon cancer. It is also used as the payload in antibody–drug conjugates (ADCs), which use a specific antibody to bring SN-38 to cancer cells, providing better efficacy with reduced toxicity.

**Product list of GeneMedi's anti-SN-38 antibody**
Cat No.	Product Description	Fc	Products Information
GTU-Bios-SN-38-Ab	Anti-Exatecan-monoclonal-antibody (mAb)	hFc/mFc	Details

All Payloads of ADCs

Application

Competitive immunoassay validation (CompetitiveELISA) and other Immunoassay,
PK & PD assay for MMAE payload of Antibody-drug Conjugate (ADC)

Highlight:

Purity: ≥95% (SDS-PAGE)
High affinityand specificity validated
High sensitivity verified by ADCs binding assay

Application
Technical Resource

Why Use Anti-SN-38 Antibody in ADC drug development?

Specificity and Sensitivity:These antibodies are essential since both free and conjugated SN-38 forms can be accurately measured alongside free antibody control while reducing interference from immunogenicity. Such antibodies allow the assays to correctly differentiate between SN-38 and its inactive carrier molecule, irinotecan, as well as other metabolites to facilitate useful pharmacokinetic evaluations.
Understanding Drug Dynamics: The application of these antibodies assists scientists in identifying where SN-38 stays within the body, how it is processed, and in which form it is ejected from the body. This involves analysis on the rate of SN-38 liberation from ADCs, the longetivity of the drug conjugation, and the availability of the free drug.
Therapeutic Monitoring and Safety: Original Title: The establishment of maintaining concise quantity for SN-38 in the body for check on therapeutic value of the drug and avoidance of toxicity. SN-38, in particular, has been reported to posses high cytotoxicity and, therefore, careful measurement of the compound’s amount is advisable.

How to use Anti-SN-38 Antibody in ADC drug development?

Development of Immunoassays: Anti-SN-38 antibodies can be utilized in sensitive immunoanalytical procedures including enzymo-linked immunosorbent assay (ELISA or radioimmunoassay(RIA)) for estimation of SN-38 in different biological fluids (plasma, serum, urine etc…). These assays are specifically intended to measure the total of both bound and free drug which includes ADC and free SN-38 and the free drug only.
Sample Collection and Analysis: In a PK study, blood, urine or tissue samples are collected at different time intervals after giving the drug. These samples are then analyzed using the developed immunoassays that incorporate anti-SN-38 antibodies developed in this study. This step is important in producing information on the likes of SN-38 and its ADC, its metabolism, distribution and excretion from the body.
Data Interpretation and Application: The data from such assays is beneficial in determination of the pharmacokinetics of SN-38 and thereby also helps in devising the dosing schedule, the toxicity issues and subsequently the therapeutic outcome of the drug. In regulatory approval and clinical trials also, the PK data are used where the trials are designed with them in mind.

Anti SN-38 antibody usage in PK studies is thus essential towards the further development and practical applicability of SN-38 based treatments such as ADCs. They make it possible to improve the quality of pharmacokinetic data that underlies therapeutic planning and achieve the best outcomes for patients and their cancer treatment.