Impact of mono- and poly-ester fractions on polysorbate quantitation using mixed-mode HPLC-CAD/ELSD and the fluorescence micelle assay.

Determination of excipient content in drug formulation is an important aspect of pharmaceutical formulation development and for analytical testing of the formulation. In this study, the influence of polysorbate subspecies, in particular mono- and poly-esters, for determining polysorbate (PS) content were investigated by comparing three of the most widely used PS quantitation approaches, the Fluorescence Micelle Assay (FMA) and Mixed-Mode High Performance Liquid Chromatography coupled with Charged Aerosol Detection (MM-CAD) or Evaporative Light Scattering Detection (MM-ELSD). FMA and MM-CAD were employed to investigate the quantitation behavior of PS20 and PS80 subspecies and corresponding degradation products in placebo formulations using forced degradation conditions at 40°C for up to 12 weeks.

The immunogenicity of antibody aggregates in a novel transgenic mouse model.

Purpose: Protein aggregates have been discussed as a potential risk factor related to immunogenicity. Here we developed a novel human IgG transgenic (tg) mouse system expressing a mini-repertoire of human IgG1 antibodies (Abs) for the assessment of immunogenic properties of human mAb preparations.

Methods: Transgenic mice were generated using germline versions of the human Ig heavy chain γ1 (IgH-γ1), and the human Ig light chain (IgL) κ and λ genes.

Structure and function of purified monoclonal antibody dimers induced by different stress conditions.

Purpose: To investigate structure and function of different monoclonal antibody (MAb) dimers.

Methods: MAb dimers were induced by process-related, low pH and UV light stress. Dimers were isolated and purified by chromatography and extensively characterized by biochemical, structural and functional methods.

The Hershey access clinic: a model for improving patient access.

Background: When waiting times for new and return patient visits at Hershey Medical Center's Department of Dermatology approached 4 and 2 months, respectively, the Hershey access clinic was implemented to increase access for patients with acute problems.

Objective: The purpose of this study was to assess the impact of the Hershey access clinic on patient care.

Results: The great majority of patients were satisfied with the access clinic.