Gemcitabine is a new cytosine derivative. Like cytarabine, it enters the human body and is activated by deoxycytidine kinase and metabolized by cytidine deaminase. This product is a pyrimidine antitumor drug, the mechanism of action is the same as that of cytarabine, and its main metabolite incorporates DNA into the cell, mainly in the G1/S phase. However, the difference is that difluorodeoxycytidine inhibits ribonucleotide reductase in addition to DNA, resulting in a decrease in intracellular deoxynucleoside triphosphate; another difference from cytarabine is that it inhibits deoxygenation. Pyrimidine deaminase reduces the degradation of intracellular metabolites and has a self-enhancing effect. Clinically, this product and cytarabine have different anti-tumor profiles and are effective against a variety of solid tumors.
For patients with advanced pancreatic cancer, as a second-line medication after fluorouracil failure, it can improve the quality of life of patients; secondly, it is a first-line application for locally advanced (stage III) and already metastatic (stage IV) non-small cell lung cancer. Recent data indicate that this product has palliative effects on ovarian cancer, breast cancer, bladder cancer, cervical cancer, liver cancer, biliary tract cancer, nasopharyngeal cancer, testicular tumor, lymphoma, mesothelioma and head and neck cancer.
482.693°C at 760 mmHg
Cool,dry and hermetic place
The dose-limiting toxicity of this product is myelosuppression, which is more common in both neutrophils and platelets. The 4-week regimen (administered on days 1, 8, and 15) had a greater effect on blood levels than the 3-week regimen (administered on days 1 and 8). This product often causes mild to moderate digestive system reactions such as constipation, diarrhea, stomatitis and so on. In addition, it can cause fever, rash, and flu-like symptoms. A small number of patients may have proteinuria, hematuria, liver and kidney dysfunction and difficulty breathing.