Chromic Phosphate Cr-51 is a radiopharmaceutical compound that has been extensively used in nuclear medicine. When administered intraperitoneally, the particulate form of chromic phosphate is pocketed in various areas of the peritoneum, or filtered out by the first lymph nodes encountered, because of the too large particle size, whereas the colloidal form is carried over to the lymphatic system. The larger particles originally present in its size spectrum or formed in vivo by aggregation of smaller particles are trapped by the first line of lymph nodes, and the remainder goes into the thoracic duct, with posterior incorporation into the blood circulation and final removal by the reticuloendothelial system: liver, spleen and bone marrow.

Mannose 6-phosphate (M6P) has type-I integral membrane receptors. M6P-receptors bind and transport M6P-enzymes to lysosomes, but it can also modulate the activity of a variety of extracellular M6P-glycoproteins (i.e., latent TGFbeta precursor, urokinase-type plasminogen activator receptor, Granzyme B, growth factors, Herpes virus). M6P has been demonstrated to reduce active TGF-β1 expression on cultured tendon fibroblasts and improved range of movement in a rabbit flexor tendon injury model. Studies of M6P in relation to skin scarring demonstrate improvement in scar cosmesis and accelerated return of normal dermal architecture. Juvidex, a formulation of M6P, inhibits the activation of TGF-beta1 and TGF-beta2, which are present at high levels in adult wounds that scar. On the other hands, M6P in a 600 mM hypertonic solution (Adaprev) potentially acts via a physical, non-chemical, hyperosmotic effect.

Oxi0-4503 (now known as combretastatin A1 phosphate), a diphosphate prodrug of combretastatin A1, was developed by Mateon therapeutics as a second-generation, dual-mechanism vascular disrupting agent from the combretastatin family. On November 21, 2012, Oxi-4503 has been granted orphan designation by the US Food and Drug Administration for the treatment of acute myelogenous leukemia. It is known that the orphan drug designation qualifies a company for several benefits, including the potential for market exclusivity, development grants, and tax credits. Oxi0-4503 is currently participating in phase I/II clinical trial the treatment of patients with acute myelogenous leukemia or myelodysplastic syndrome. In addition, phase I clinical trial was successfully completed where was studied the safety of Oxi0-4503 in patients with advanced solid tumors.

Norcodeine is the N-demethylated derivative of codeine. It has relatively little opioid activity in its own right, but is formed as a metabolite of codeine following ingestion. Codeine and its other major metabolites codeine-6-glucuronide and norcodeine have weak affinity to opioid μ-receptors.

Fosbretabulin (Combretastatin A4 phosphate, CA4P) is the lead compound of a relatively new class of agents termed vascular disrupting agents that target existing tumor blood vessels. Rapid tumor blood flow shutdown has been demonstrated in preclinical models and patients by various techniques such as dynamic contrast-enhanced MRI, perfusion computed tomography and PET scans following CA4P infusion. CA4P typically induces rapid tumor necrosis in the center of the tumor and leaves a rim of viable cells in the periphery. In oncology, CA4P does not appear to be that active by itself, but may be more efficacious when combined with chemotherapy, antiangiogenic therapy and radiation therapy. Combretastatin was initially isolated from the root bark of the South African Bush willow Combretum caffrum in 1982 by Pettit and colleagues at the Arizona State University (AZ, USA). Combretastatin A4 phosphate binds avidly to tubulin at the colchicine-binding site to inhibit microtubule assembly and destabilize the cytoskeleton. CA4P is a tubulin-binding agent that binds at or near the colchicine binding site of β-tubulin (Kd = 0.40 uM), inhibits tubulin assembly with IC50 of 2.4 uM. Fosbretabulin has orphan drug status in the EU and the US for the treatment of ATC (Anaplastic Thyroid Cancer). Later the development of this drug was discontinued.