Activated carbon particles as anti-cancer drug carrier into regional lymph nodes.

The effect of a new dosage form for anti-cancer agents was studied on tissue distribution and compared with the aqueous solution form. The new dosage form, developed in order to distribute a greater amount of the agent to regional lymph nodes, comprises polyvinylpyrrolidone and small activated carbon particles adsorbing pepleomycin (PEP-CH) or mitomycin C (MMC-CH) in saline. Pepleomycin at 500 micrograms/kg or mitomycin C at 250 micrograms/kg were injected into the gastric wall of dogs in the new dosage form or the aqueous solution form. The activity level of the agents in tissues was bioassayed within 24 h after injection by the thin agar plate method. Statistically, the new dosage form maintained an activity level in lymph nodes that was significantly higher than the aqueous solution form (ratio of PEP-CH to solution form, 6-32 times in 24 h; MMC-CH, 100-1000 times in 6 h; p less than 0.05-0.01), and a concentration in blood that was significantly lower (PEP-CH, about 1/2 times in 2 h; MMC-CH, 1/10-1/5 times in 1 h; p less than 0.05).