Lyophilized Formulations of Recombinant Tumor Necrosis Factor

Recombinant tumor necrosis factor-alpha (TNF), an investigational biological response modifier, is a protein and is susceptible to particulate generation during handling in dilute aqueous solutions. TNF is prone to formation of nonreducible dimers and oligomers during formulation, lyophilization, and storage. The effect of various parameters, such as the pH, protein concentration, and nature of excipients present during lyophilization, on the formation of nonreducible dimers and oligomers was investigated. The results of these studies indicate that these parameters can significantly alter the rate of this reaction. Inclusion of an amorphous buffer and an appropriate amount of a crystallizing sugar (mannitol) combined with a suitable quantity of an amorphous protectant (dextran, sucrose, trehalose, or 2-hydroxypropyl--cyclodextrin) was shown to reduce the formation of these dimeric and oligomeric species during lyophilization. Representative lyophilized formulations of TNF based on selected amorphous excipients were found to be fully bioactive and stable over 9 months.