The present invention relates to compositions and methods of formulating nanoparticle drugs for cancer treatment in particular for intravenous administration in particular nanoparticle formulations containing cytotoxic drugs for the treatment of cancer. The compositions may have properties which facilitate the release of drugs into the patient including being unstable in plasma/blood, having low AUC, low Cmax, high Vd, CMC above theoretical Cmax of the drug, high tumor/plasma AUC. The present invention also provides for methods of administration and compositions which are unstable after administration to a patient so that the cytotoxic drug may bind to endogenous proteins such as albumin and be delivered to tumors in the patient.