Abstract: The present invention provides a general method to retard the precipitation inception time for poorly water-soluble camptothecin analogues from a supersaturated solution by a chemical conversion approach via pH alteration. This method is successfully utilized to prepare stable parenteral formulations for silatecan 7-t-butyldimethylsilyl-10-hydroxycamptothecin (DB-67), a poorly water-soluble lipophilic camptothecin analogue, in aqueous solutions containing &bgr;-cyclodextrin sulfobutyl ether (SBE-CD) or other solubilizing agents. The formulations manufactured by this method are more simple and cost-effective, of higher doses and better quality in terms of manufacture loss and formulation stability, and can be free of organic solvents (e.g., DMSO or N-methyl-2-pyrrolidinone).