Industry Perspective on Temperature Cycling Studies to Meet Regulatory Temperature Excursion Support Requirements: Survey Outcome and Recommendations.

Temperature cycling stability studies can be appropriately designed and utilized to ensure that drug product quality, efficacy, and safety are not compromised when materials are subjected to short term temperature excursions from intended storage that may occur during e.g., shipping, transport, or patient use. Some countries, such as Australia and Brazil, impose specific regulations that specify the need to conduct stability studies that are supportive of "real world" excursions as part of licensing approval requirements. These temperature cycling stability studies extend beyond what is described in ICH Guidelines Q1A(R2) and Q5C, and companies may be challenged in designing studies that not only satisfy country specific regulations, but also satisfy all global regulatory health authority expectations. This article focuses on responses to a cross-industry survey conducted within the International Consortium for Innovation and Quality (iqconsortium.org) member companies, regarding practices related to temperature cycling stability studies, in order to determine how these requirements are being interpreted and met. The results indicate that while there is no one-size-fits-all approach to performing temperature cycling stability studies, there are common and best practices that can be followed to satisfy global health authority regulatory guidelines and requirements. PURPOSE: The purpose of this paper is to describe the outcome of an industry survey and common/best practices on temperature cycling stability studies performed on drug product (DP) to satisfy the requirements established for marketing authorizations in Australia and Brazil or any other countries that may have similar requirements. The framework is proposed within the context of late phase and commercial development of common biological and/or large molecule modalities, such as monoclonal antibodies (mAbs, including bispecific antibodies), fusion proteins, complex proteins, oligonucleotides, and antibody-drug conjugates (ADCs), but many of the general principles involved may be applied to other therapeutics, such as Virus Like Particles (VLP), gene or cell therapies (GTx or CTx), or vaccines. For the purposes of this paper, temperature cycling stability studies refer to studies that are designed, in part, to support short term temperature excursions that drug product may be subjected to during shipping and storage activities and is outside of the labeled storage condition of the product.

Cartilage tissue enhances proteoglycan retention by nucleus pulposus cells in vitro.

OBJECTIVE: To investigate the effect of cartilage on nucleus pulposus (NP) tissue in an in vitro model. METHODS: Cells were isolated from bovine NP or articular cartilage and allowed to form tissue in vitro. The NP tissue was grown either alone or in the presence of cartilage tissue (coculture) for up to 4 weeks and examined for histologic appearance, gene expression, and biochemical composition. For selected experiments, NP tissue was grown in coculture with fragments of cartilage end-plate. RESULTS: Coculture of in vitro-formed NP tissue with cartilage end-plate tissue resulted in a significant increase in proteoglycan content in the NP tissue by 2 weeks, compared with NP tissue grown alone. Substituting in vitro-formed cartilage tissue for cartilage end-plate also had a positive effect on the NP tissue, suggesting that it was an appropriate substitute for cartilage end-plate. Coculture of NP with in vitro-formed cartilage for 2 weeks increased aggrecan and collagen gene expression compared with that in NP tissue grown alone, and also reduced expression of matrix metalloproteinase 3 (MMP-3), MMP-13, and ADAMTS-5. NP cells from older and younger animals responded similarly to in vitro-formed cartilage. Expression of genes for tumor necrosis factor α (TNFα) and TACE in NP cells was higher when grown in the absence of cartilage. This corresponded with increased TNFα protein levels in the absence of cartilage. CONCLUSION: The data suggest that chondrocytes may secrete a factor(s) that positively enhances tissue growth, perhaps by inhibiting TNFα production. This could be a potential mechanism explaining how loss of the cartilage end-plate may contribute to the development of NP degenerative changes.

Drosophila melanogaster Cad99C, the orthologue of human Usher cadherin PCDH15, regulates the length of microvilli.

Actin-based protrusions can form prominent structures on the apical surface of epithelial cells, such as microvilli. Several cytoplasmic factors have been identified that control the dynamics of actin filaments in microvilli. However, it remains unclear whether the plasma membrane participates actively in microvillus formation. In this paper, we analyze the function of Drosophila melanogaster cadherin Cad99C in the microvilli of ovarian follicle cells. Cad99C contributes to eggshell formation and female fertility and is expressed in follicle cells, which produce the eggshells. Cad99C specifically localizes to apical microvilli. Loss of Cad99C function results in shortened and disorganized microvilli, whereas overexpression of Cad99C leads to a dramatic increase of microvillus length. Cad99C that lacks most of the cytoplasmic domain, including potential PDZ domain-binding sites, still promotes excessive microvillus outgrowth, suggesting that the amount of the extracellular domain determines microvillus length. This study reveals Cad99C as a critical regulator of microvillus length, the first example of a transmembrane protein that is involved in this process.