Consistent manufacturing and quality control of a highly complex recombinant polyclonal antibody product for human therapeutic use.

The beneficial effect of antibody therapy in human disease has become well established mainly for the treatment of cancer and immunological disorders. The inherent monospecificity of mAbs present limitations to mAb therapy which have become apparent notably in addressing complex entities like infectious agents or heterogenic endogenous targets. For such indications mixtures of antibodies comprising a combination of specificities would convey more potent biological effect which could translate into therapeutic efficacy. Recombinant polyclonal antibodies (rpAb) consisting of a defined number of well-characterized mAbs constitute a new class of target specific antibody therapy. We have developed a cost-efficient cell banking and single-batch manufacturing concept for the production of such products and demonstrate that a complex pAb composition, rozrolimupab, comprising 25 individual antibodies can be manufactured in a highly consistent manner in a scaled-up manufacturing process. We present a strategy for the release and characterization of antibody mixtures which constitute a complete series of chemistry, manufacturing, and control (CMC) analytical methods to address identity, purity, quantity, potency, and general characteristics. Finally we document selected quality attributes of rozrolimupab based on a battery of assays at the genetic-, protein-, and functional level and demonstrate that the manufactured rozrolimupab batches are highly pure and very uniform in their composition.

Allergen-specific polyclonal antibodies reduce allergic disease in a mouse model of allergic asthma.

BACKGROUND: Recombinant allergen-specific immunoglobulin G (IgG) antibody therapy can reduce allergic asthma symptoms by inhibiting the immunoglobulin E (IgE)-mediated allergic response. This study investigated the effect of intranasally administered allergen-specific monoclonal (mAb) and polyclonal (pAb) antibody on airway inflammation and hyperresponsiveness (AHR) in a mouse model of human asthma. METHODS: Ovalbumin (OVA)-specific IgG2b antibodies were generated by phage display using spleens from OVA-immunized mice, and screening against OVA and finally expressed in CHO cells. Sensitized mice were treated intranasally with either a recombinant anti-OVA mAb (gc32) or a polyclonal preparation comprising seven selected antibodies (including gc32). Control mice received diluent only, OVA only, a control polymeric IgG or dexamethasone. Following challenge with nebulized OVA, investigators assessed airway inflammation by histology and cellular composition of the bronchoalveolar fluid, and methacholine-induced airway hyperresponsiveness (AHR). Serum levels of total and OVA-specific IgE were measured by ELISA. RESULTS: Sensitized mice developed airway inflammation and AHR in response to OVA challenge. Intranasally administered OVA-specific murine polyclonal or monoclonal IgG2b antibodies both reduced OVA-induced lung inflammation. Polyclonal, but not anti-OVA mAb, also reduced AHR and eosinophil influx into the airway lumen. Both anti-OVA antibody preparations reduced levels of specific IgE with no effect on total IgE levels. CONCLUSIONS: Intranasal treatment with allergen-specific pAb reduces pulmonary inflammation and AHR in a mouse model of allergic asthma, but allergen-specific mAb reduces inflammation only. Allergen-specific recombinant pAb offers a potentially valuable therapeutic approach to the management of allergic asthma.

Characterization of different cell culture media for expression of recombinant antibodies in mammalian cells: Presence of contaminating bovine antibodies.

Several new cell culture media designed specifically for the expression of recombinant antibodies in Chinese hamster ovary (CHO) cells were investigated for the presence of bovine IgG. Three serum-free media, three protein-free (animal component free) media, as well as one chemically defined medium were included in the study. Employing a combination of affinity chromatography (Protein G or A columns), SDS-PAGE analysis, and peptide mass fingerprinting, two of the serum-free media were found to contain bovine IgG in the range of approximately 0.5 mg/L. The other five media did not contain detectable levels of contaminating Protein A or G-binding proteins such as bovine IgG.