Alnylam’s ONPATTRO to Treat Patients with Hereditary ATTR Amyloidosis in Adults
Our research focused on developing ion-pairing HPLC methods with UV detection for the precise determination of two widely used chelating agents: ethylenediaminetetraacetic acid (EDTA) in Abilify® oral solution and diethylenetriaminepentaacetic acid (DTPA) in Yervoy® intravenous formulation. Since EDTA and DTPA lack chromophores, we introduced transition metal ions (Cu2+, Fe3+) during sample preparation to form stable metallocomplexes that enhance UV detection. This novel approach utilizing metallocomplexes in ion-pairing chromatography enabled us to achieve the desired sensitivity and selectivity. Copper was employed for EDTA determination, while iron was utilized for DTPA determination.
For EDTA analysis, a gradient mobile phase effectively separated the formulation components from the analyte. In the case of DTPA, the active drug substance, ipilimumab, was eluted in the void. Additionally, we explored optimizing the ion-pairing reagent concentration to enhance retention of aminopolycarboxylic acids (APCAs) such as EDTA and DTPA, ultimately improving method specificity. The development of these analytical methods took into account the chromatographic properties of the analytes, the nature of the sample matrix, and the intended purpose of the method.
Validation data were presented for both methods, demonstrating their accuracy and reliability. Ultimately, these methods proved successful in determining the fate of the chelates, providing valuable insights into their behavior.
