Small cell lung cancer (SCLC) is a rapidly developing, invasive lung cancer that accounts for about 15% of all lung cancer cases. Among them, about three-quarters of patients with small cell lung cancer are already in the “extensive phase” when they are diagnosed, which means extensive metastasis has occurred in their lungs or other parts of the body. After the initial platinum-based chemotherapy, patients are prone to relapse and the prognosis is extremely poor. According to statistics, only 6% of patients with small cell lung cancer can survive more than 5 years. Therefore, they need more effective therapies to control the disease. In recent years, immune checkpoint inhibitors have shown promise for the treatment of lung cancer. Since cancer cells sometimes use checkpoints to avoid being attacked by the immune system, we can use drugs that target these checkpoints to treat patients with SCLC. Durvalumab and Pabolizumab are the two most promising inhibitor drugs for the treatment of lung cancer.
Imfinzi is qualified for FDA priority review
Recently, AstraZeneca announced that the US FDA has accepted its supplementary biologics license application (sBLA) for its immunotherapy Imfinzi (durvalumab) and granted priority to the application for review. Before the end of the first quarter of next year, the FDA will make a reply. Targeting at patients with small cell lung cancer who have not previously been treated, Imfinzi is expected to be the second PD-L1 inhibitor approved for first-line treatment of small cell lung cancer soon after Roche’s Tecentriq.
As a PD-L1 inhibitor, Imfinzi has shown positive results in a phase 3 clinical trial called CASPIAN. When combined with standard chemotherapy, it can significantly extend the overall survival (OS) of patients. Data show that patients can reduce their risk of death by 27%, with a median overall survival of 13.0 months. In comparison, the control group using only standard chemotherapy had data of 10.3 months. After 18 months of treatment, 33.9% of patients in the treatment group were still alive, while in the control group this number was only 24.7%.
Pembrolizumab helps to treat advanced lung cancer
The median overall survival of patients with lung cancer who had received Taxotere chemotherapy in the past was only 5.7 months, and meanwhile, there are many side effects that would affect patients’ quality of life. A recent study showed that the median overall survival of pembrolizumab, an immunotherapy anti-PD-1 drug, was 12 months, which is relatively good result compared with Taxotere.
Pembrolizumab is the first drug approved by the US FDA as an immunotherapy for squamous and non-squamous metastatic non-small cell lung cancer. Research data show that nearly 90% of patients with PD-L1 high expression lung cancer have tumor shrinkage after treatment with pembrolizumab, and nearly 60% of patients with low expression of PD-L1 have the same positive response. In addition, the anti-PD-1 drug pembrolizumab has high safety, and the adverse event rate is as low as 1-2%. At the same time, multiple studies have shown that pembrolizumab has a positive effect in the treatment of various cancer treatments.