Determining the Clearance of Degraded Protein via a Monoclonal Antibody Purification Process in Support of Cleaning Carryover Limits in Multiproduct Facilities.

Cleaning validation acceptance criteria in multiproduct facilities are established using maximum allowable carryover calculations. Carryover calculations incorporate the shared equipment surface area between two products to ensure that an acceptable limit for residue from the previously manufactured product to the subsequent product is determined. The shared surface area can be limited to areas where carryover presents the highest risk to product quality or patient safety. In these cases, specifically for biologic drug substance manufacturing, the shared surface area is limited to equipment after the purification process based on the assumption that the purification process would remove potential product fragment residues from the previous product. Until now, this assumption has been based on empirical knowledge without experimental data quantifying the clearance or removal of potential residues. We present a three-part study that determined the effects of cleaning conditions on selected monoclonal antibodies (mAbs) and the generation of degraded fragments and evaluated the clearance of both the degraded mAb1 in a laboratory setting and the degraded fragments in the presence of a subsequent product, assessing the risk of co-purification. Several analytical techniques were used, including gel electrophoresis, capillary zone electrophoresis/laser-induced florescence detection, and liquid chromatography-mass spectrometry. Protein fragment generation was demonstrated for five different mAbs from different immunoglobulin G subclasses. The clearance of the degraded fragments in the absence and presence of the subsequent product was demonstrated by calculating fold clearance and log reduction value (LRV) for each chromatography step. The data showed that the fragments generated during cleaning could be removed by the purification process. The fold clearances were determined to be values of 5400 (3.7 LRV) in the absence of subsequent product and 4428 (3.6 LRV) in the presence of subsequent product. The results supported the removal of product residues from shared surface areas by the purification process in multiproduct biologic drug substance manufacturing facilities.

Mitigation options for sediment and phosphorus loss from winter-sown Arable Crops.

Sediment and P inputs to freshwaters from agriculture are a major problem in the United Kingdom (UK). This study investigated mitigation options for diffuse pollution losses from arable land. Field trials were undertaken at the hillslope scale over three winters at three UK sites with silt (Oxyaquic Hapludalf), sand (Udic Haplustept), and clay (Typic Haplaquept) soils. None of the mitigation treatments was effective in every year trialled, but each showed overall average reductions in losses. Over five site years, breaking up the compaction in tramlines (tractor wheel tracks) using a tine reduced losses of sediment and P to losses similar to those observed from areas without tramlines, with an average reduction in P loss of 1.06 kg TP ha(-1). Compared to traditional plowing, TP losses under minimum tillage were reduced by 0.30 kg TP ha(-1) over five site years, TP losses under contour cultivation were reduced by 0.30 kg TP ha(-1) over two site years, and TP losses using in-field barriers were reduced by 0.24 kg TP ha(-1) over two site years. In one site year, reductions in losses due to crop residue incorporation were not significant. Each of the mitigation options trialled is associated with a small cost at the farm-scale of up to pound5 ha(-1), or with cost savings. The results indicate that each of the treatments has the potential to be a cost-effective mitigation option, but that tramline management is the most promising treatment, because tramlines dominate sediment and P transfer in surface runoff from arable hillslopes.