In the long process of human struggle with tumors, the immune system plays a big role. Cancer appears when the immune system is suppressed and overwhelms cancer cells. In the past two years, cancer immunotherapy has developed very rapidly, especially for PD1/PD-L1 immune checkpoint inhibitors, drugs have emerged in an endless stream, imported drugs and domestic original research drugs have added up to more than ten kinds, domestic prices have dropped significantly, but also for patients to provide more choices.
Today we introduce a broad-spectrum immune checkpoint inhibitor that has just been listed in the domestic original research - slulizumab.
On March 24, 2022, the innovative PD-1 inhibitor Slulizumab independently developed by The Mainland was officially approved for marketing by the State Drug Administration of China (NMPA) for the treatment of adult patients with advanced solid tumors of unresectable or metastatic microsatellites (MSI-H). In layman's terms, as long as MSI-H is present through genetic testing, slulizumab can be used regardless of any kind of advanced cancer.
What is a microsatellite highly unstable solid tumor?
Microsatellites (MS), also known as simple repeat sequences, ARE found throughout the human genome and are thought to play an important role in maintaining genome stability and regulating gene expression. Insertion or deletion at the time of DNA replication causes a change in the length of the microsatellite sequence, known as "microsatellite" instability (MSI). Highly microsatellite instability, MSI-H, is a type of cancer cell that has more genetic markers than normal cells, namely short, repetitive DNA sequences. Mismatched DNA is usually repaired when cells copy DNA, and cancer cells with a large number of microsatellites may have defects in this function, also known as mismatch repair defects, or dMMR. MSI-H and dMMR account for 5% to 15% of patients with solid tumors. It is most commonly found in colorectal, endometrial, gastric, and thyroid cancers, but may also occur in lung, breast, prostate, bladder, and thymus cancers, but at a lower rate.
The approval of Slullizumab for marketing is based on the "Key Phase II Clinical Study on the Treatment of MSI-H/dMMR Solid Tumors by Slullizumab" led by Qin Shukui and Professor Li Jin (ASTRUM010 study). The results showed that the objective response rate (ORR) of the colorectal cancer subgroup was as high as 46.7% in 45 patients with sensitivity efficacy analysis, and the disease control time of patients was long, and the 12-month survival (OS) rate of 58 patients with sensitive efficacy analysis was 82.4%. In terms of safety, the overall tolerance of patients is good.
In fact, slulizumab is currently the fourth pan-tumor immunotherapy drug approved in mainland China, imported O drugs and K drugs have long been approved for MSI-H/dMMR cancer patients, and the domestic PD-L1 inhibitor envolumab was also approved for MSI-H/dMMR advanced cancer patients in November 2021.
It is worth mentioning that in December 2021, the first-line treatment of slullizumab for extensive phase Iii of small cell lung cancer reached the main endpoint, which is the first PD-1 monoclonal antibody drug to achieve a breakthrough in the field of small cell lung cancer. It is estimated that in the near future, slulizumab will be approved as an indication for small cell lung cancer, which also brings hope to the majority of small cell lung cancer patients.