Formulations of bendamustine

A long term storage stable bendamustine-containing composition, comprising:

• a) bendamustine or a pharmaceutically acceptable salt thereof;
• and
• b) a pharmaceutically acceptable fluid comprising
• i) 90% polyethylene glycol and 10% propylene glycol;
• ii) sodium hydroxide in an amount sufficient to obtain a pH of from about 6.5 for the polyethylene glycol, as measured using the USP monograph for polyethylene glycol;
• and
• iii) thioglycerol at a concentration of about 5 mg/mL;
• said bendamustine-containing composition having less than about 5% total polyethylene glycol esters and propylene glycol esters, on a normalized peak area response (“PAR”) basis as determined by high performance liquid chromatography (“HPLC”) at a wavelength of 223 nm, after at least about 15 months of storage at a temperature of from about 5° C. to about 25° C.

A long term storage stable bendamustine-containing composition, comprising:

• a) bendamustine or a pharmaceutically acceptable salt thereof at a concentration of about 25 mg/mL;
• and
• b) a pharmaceutically acceptable fluid comprising
• i) 90% polyethylene glycol and 10% propylene glycol;
• ii) sodium acetate in an amount sufficient to obtain a pH of about 6.5 for the polyethylene glycol, as measured using the USP monograph for polyethylene glycol;
• and
• iii) thioglycerol at a concentration of about 5 mg/mL;
• said bendamustine-containing composition having less than about 5% total polyethylene glycol esters and propylene glycol esters, on a normalized peak area response (“PAR”) basis as determined by high performance liquid chromatography (“HPLC”) at a wavelength of 223 nm, after at least about 15 months of storage at a temperature of from about 5° C. to about 25° C.

A long term storage stable bendamustine-containing composition, comprising:

• a) bendamustine or a pharmaceutically acceptable salt thereof;
• and
• b) a pharmaceutically acceptable fluid comprising
• i) a mixture of polyethylene glycol, and propylene glycol;
• ii) an organic compound or an inorganic compound in an amount sufficient to obtain a pH of from about 3.3 to about 4.2 for the long term storage stable bendamustine-containing composition, as measured using the USP monograph for polyethylene glycol;
• and
• iii) a stabilizing amount of an antioxidant;
• said bendamustine-containing composition having less than about 5% total polyethylene glycol esters and propylene glycol esters, on a normalized peak area response (“PAR”) basis as determined by high performance liquid chromatography (“HPLC”) at a wavelength of 223 nm, after at least about 15 months of storage at a temperature of from about 5° C. to about 25° C.