RT Journal Article
SR Electronic
T1 Stability of Cyclophosphamide in Lyophilized Cakes, II. Urea. Polyvinylpyrrolidone, and Dextran as Excipients
JF PDA Journal of Pharmaceutical Science and Technology
JO PDA J Pharm Sci Technol
FD Parenteral Drug Association (PDA)
SP 165
OP 173
VO 42
IS 5
A1 Kovalcik, Thomas R.
A1 Guillory, J. Keith
YR 1988
UL http://journal.pda.org/content/42/5/165.abstract
AB Lyopilized products containing cyclophosphamide and one of the following excipients: urea, polyvinylpyrrolidone (PVP-40), or dextran, were prepared. All of the products were well-formed cakes. Cyclophosphamide in these lyophilized cakes was found to undergo rapid(t90 (30 days) degradation in the solid state at room temperature. The lyophilized cakes were humidified with five microliters of water. In the cake containing urea, differential scanning calorimetry, and X-ray diffraction showed that cyclophosphamide was converted from the amorphous to the monohydrate form when exposed to moisture, and exhibited improved stability. In the case of the cake containing PVP-40, the incorporation of moisture resulted in formation of a clear, semi-solid possessing poor stability. The cyclophosphamide/dextran cake remained intact upon humidification. Differential scanning calorimetry and X-ray diffraction showed that cyclophosphamide in this cake was not converted from the amorphous form to the monohydrate form, and exhibited no improvement in stability.