Many customers have asked us how our liposome doxorubicin, Doxoves™, compares to the commercial product Doxil®. Doxoves™ is prepared by scientists from the former Sequus Pharmaceuticals that developed Doxil®, by the same methodology as Doxil®. Doxoves™ contains the same lipid composition and drug/lipid ratio. Liposome down-sizing is achieved by extrusion using a Lipex extruder, and the transmembrane ammonium gradient is established by diafiltration, the proper technique for large scale manufacturing of liposome products. Doxoves™ exhibits comparable physical characteristics regarding particle size (approx. 85nm), narrow distribution, and drug encapsulation efficiency (>98%), and uses the same bulk buffer solution (10wt% sucrose, 10mM histidine, pH 6.5). Doxoves™ is sterile filtered and filled in autoclaved glass vials for long-term stability. However, Doxoves™ is provided at 4mg/mL drug concentration (compared to 2mg/mL Doxil®) in order to allow researchers to conduct experiments at much higher drug concentrations/doses.
Below you will find some results which we have obtained from research with Doxoves™. Cryo-TEM conducted at NanoImaging Services showed consistent particle size, predominantly unilamellar structure and the rod-like structures of the doxorubicin/sulfate co-crystals inside the liposomes. Results from a recent PK study in rats showed a similar plasma drug PK profile to that of Doxil® with a plasma drug half-life of 30 - 40 hrs. The two batches of Doxoves™ showed identical PK profiles and parameters. You will also find a typical certificate of analysis of Doxoves™ here.
However, please keep in mind that although we have confidence in the quality of Doxoves™, it nevertheless is a research grade liposomal doxorubicin product. It is not manufactured under cGMP conditions. We have not conducted any investigations regarding its biodistributions in tissues and/or in tumors, toxicity and/or antitumor efficacy in house or sponsored by FormuMax.
Pharmacokinetic studies of Doxoves™ in Rats