PEGylated recombinant human tumor necrosis factor alpha: pharmacokinetics and anti-tumor effects

The aim of the present work was to investigate and assess the merit of PEGylated recombinant human tumor necrosis factor-alpha (rHuTNF-alpha) following our previous work. The rHuTNF-alpha was modified using activated polyethylene glycol (PEG), N-succinimidyl succinnate monomethoxy polyethylene glycol (SS-PEG). The pharmacokinetics and anti-tumor effect were investigated. The experimental results showed that PEGylated rHuTNF-alpha could obviously alter in vivo behavioral characteristics of rHuTNF-alpha. Among the synthesized PEG-rHuTNF-alphas with different PEG molecules, PEG20000-rHuTNF-alpha demonstrated the longest circulating half-life (24.8 h) which was about 50 times longer than that of rHuTNF-alpha (28.8 min). In addition, there was much more PEG20000-rHuTNF-alpha distributed into tumor tissues than other PEG-rHuTNF-alphas or rHuTNF-alpha with time, and PEG20000-rHuTNF-alpha also showed the highest anti-tumor potency. These results indicated that PEG20000-rHuTNF-alpha was a useful long circulating molecule with selective localization in tumor tissues and enhanced anti-tumor activity of rHuTNF-alpha.