OncoSec Medical Inc (ONCSQ)

[guti]

TitanV, those results look very promising, with the addition of one patient exhibiting locoregional shrinkage of distant untreated melanoma nodules. It is incredible that the 62yr old experienced a complete clinical resolution of all treated lesions after only 1 cycle of IL-12 and 2 cycles of pembrolizumab.

It is also encouraging that the one 69-year-old female patient after 2 cycles of IL-12 and 4 cycles of pembrolizumab experienced a positron emission tomography (PET)/computed tomography (CT). It confirmed complete response of the target lesion, and had no other sites of disease by the fifth cycle of treatment. I am not sure if it was done without the use of a tracer, but I am thinking that’s what they meant.

A positron emission tomography (PET) scan is an imaging test that helps reveal how tissues and organs are functioning. A PET scan uses a radioactive drug (tracer) to show this activity. The tracer may be injected, swallowed or inhaled, depending on which organ or tissue is being studied by the PET scan. The tracer collects in areas of the body that have higher levels of chemical activity, which often correspond to areas of disease. On a PET scan, these areas show up as bright spots. It seems the reaction of IL-12 with anti PD-1 is allowing those areas to show without the use of radiation that is found in the tracer. PET scanning with the tracer fluorine-fluorodeoxyglucose (FDG) is widely used in clinical oncology. A typical dose of FDG used in an oncological scan has an effective radiation dose of 14 mSv.

Most tissues cannot remove the phosphate added with the FDG. This means that FDG is trapped in any cell that takes it up, until it decays. This results in intense radiolabeling of tissues with high glucose uptake, such as the brain, the liver, and most cancers. As a result, FDG-PET can be used for diagnosis, staging, and monitoring treatment of cancers, particularly in Hodgkin's lymphoma, non-Hodgkin lymphoma, and lung cancer. That would be great for doctors if they can look for progress without the need of radiation, especially keeping in mind that patients are non-responders. The more quickly information can be gathered, the higher percentage of survival.

http://www.cancernetwork.com/oncology-journal/review-novel-intralesional-therapies-melanoma-emphasis-potential-combination-approach