In Vivo Anti-Tumor Activity of Polypeptide HM-3 Modified by Different Polyethylene Glycols (PEG)

HM-3, designed by our laboratory, is a polypeptide composed of 18 amino acids. Pharmacodynamic studies in vivo and in vitro indicated that HM-3 could inhibit endothelial cell migration and angiogenesis, thereby inhibiting tumor growth. However, the half-life of HM-3 is short. In this study, we modified HM-3 with different polyethylene glycols (PEG) in order to reduce the plasma clearance rate, extend the half-life in the body, maintain a high concentration of HM-3 in the blood and increase the therapeutic efficiency. HM-3 was modified with four different types of PEG with different molecular weights (ALD-mPEG5k, ALD-mPEG10k, SC-mPEG10k and SC-mPEG20k), resulting in four modified products (ALD-mPEG5k-HM-3, ALD-mPEG10k-HM-3, SC-mPEG10k-HM-3 and SC-mPEG20k-HM-3, respectively). Anti-tumor activity of these four modified HM-3 was determined in BALB/c mice with Taxol as a positive control and normal saline as a negative control. Tumor weight inhibition rates of mice treated with Taxol, HM-3, ALD-mPEG5k-HM-3, ALD-mPEG10k-HM-3, SC-mPEG10k-HM-3 and SC-mPEG20k-HM-3 were 44.50%, 43.92%, 37.95%, 31.64%, 20.27% and 50.23%, respectively. Tumor inhibition rates in the Taxol, HM-3 and SC-mPEG20k-HM-3 groups were significantly higher than that in the negative control group. The efficiency of tumor inhibition in the SC-mPEG20k-HM-3 group (drug treatment frequency: once per two days) was better than that in the HM-3 group (drug treatment frequency: twice per day). In addition, tumor inhibition rate in the SC-mPEG20k-HM-3 group was higher than that in the taxol group. We conclude that SC-mPEG20k-HM-3 had a low plasma clearance rate and long half-life, resulting in high anti-tumor therapeutic efficacy in vivo. Therefore, SC-mPEG20k-HM-3 could be potentially developed as new anti-tumor drugs

Inequality, Inc

To engage with inequality, I explore how corporate governance theory is based on inherently contingent ideas of the legal and organizational structuring of the modern public corporation in a corporate ‘architecture’ and how these contingent ideas affect the distribution of privileges, protections and proceeds to different types of actors. I argue that the currently dominant corporate governance theory ignores a specific corporate architecture that provided internal and external legitimacy to the modern public corporation by embedding a set of trade-offs between constituent groups and cementing those trade-offs into a broader institutional setting. Ignoring this architecture leads to the redirection of the privileges and protections embodied in the modern corporation to the exclusive benefit of an implicit coalition of market value-oriented shareholders and managers, while the risks to all other actors, interests and timeframes are relegated to the status of ‘externalities’. I explore how a focus on contingent conceptions of the modern corporation and of corporate governance provides an organizational-level explanation for growing inequality with which existing sectoral and state-centric approaches and means for engagement can be complemented

The global biopharma industry and the rise of Indian drug multinationals: implications for Australian generics policy

This article provides a synopsis of the new dynamics of the global biopharma industry. The emergence of global generics companies with capabilities approximating those of 'big pharma' has accelerated the blurring of boundaries between the innovator and generics sectors. Biotechnology-based products form a large and growing segment of prescription drug markets and regulatory pathways for biogenerics are imminent. Indian biopharma multinationals with large-scale efficient manufacturing plants and growing R&D capabilities are now major suppliers of Active Pharmaceutical Ingredients (APIs) and generic drugs across both developed and developing countries. In response to generic competition, innovator companies employ a range of life cycle management techniques, including the launch of 'authorised generics'. The generics segment in Australia will see high growth rates in coming years but the prospect for local manufacturing is bleak. The availability of cheap generics in international markets has put pressure on Pharmaceutical Benefits Scheme (PBS) pricing arrangements, and a new policy direction was announced in November 2006. Lower generics prices will have a negative impact on some incumbent suppliers but industrial renewal policies for the medicines industry in Australia are better focused on higher value R&D activities and niche manufacturing of sophisticated products