DepoDur (morphine sulfate) extended-release liposome injection is a sterile suspension of multivesicular liposomes using proprietary DepoFoam® formulation technology containing morphine sulfate, intended for epidural administration.

Chemically, morphine sulfate is 7, 8-didehydro-4, 5α-epoxy-17-methylmorphinan-3, 6α -diol sulfate (2:1) (salt) pentahydrate with a molecular weight of 758. Morphine sulfate pentahydrate has the following structural formula:

Morphine base has a pK_a of 7.9, with an octanol/water partition coefficient of 1.42 at physiologic pH 7.4. At this pH, morphine's tertiary amino group is mostly ionized, making the molecule water-soluble.

DepoDur (morphine sulfate xr liposome injection) is a sterile, non-pyrogenic, white to off-white, preservative-free suspension of multivesicular lipid-based particles containing

Morphine Sulfate, USP. The median diameter of the liposome particles is in the range of 17 to 23 µm. The liposomes are suspended in a 0.9% sodium chloride solution. Each vial contains morphine sulfate (expressed as the pentahydrate) at a nominal concentration of 10 mg/mL. Inactive ingredients and their approximate concentrations are: 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 4.2 mg/mL; cholesterol, 3.3 mg/mL; 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG), 0.9 mg/mL; tricaprylin, 0.3 mg/mL; and triolein, 0.1 mg/mL. The pH of DepoDur (morphine sulfate xr liposome injection) is in the range of 5.0 to 8.0.

After the administration of DepoDur into the epidural space, morphine sulfate is released from the multivesicular liposomes over a period of time.

Liposomal encapsulation or incorporation in a lipid complex can substantially affect a drug's functional properties relative to those of the unencapsulated or nonlipid-associated drug. In addition, different liposomal or lipid-complexed products with a common active ingredient may vary from one another in the chemical composition and physical form of the lipid component. Such differences may affect functional properties of these drug products. DO NOT SUBSTITUTE.

Last reviewed on RxList: 10/13/2009
This monograph has been modified to include the generic and brand name in many instances.