Cervical cancer caused by HPV infection is a common malignant tumor that seriously endangers women's health. Preventive vaccination against cervical cancer can effectively prevent HPV-induced infection, thereby preventing the incidence of cervical cancer. According to statistics from International Agency for Research on Cancer (IARC) in 2018, there are approximately 569,800 new cases of cervical cancer and approximately 311,400 people die from cervical cancer worldwide each year. China's National Cancer Center reported that 98,900 people were diagnosed with cervical cancer in China and the number of deaths was 30,500 in 2015.
Human papillomavirus belongs to the Papillomaviridae family and is a class of small non-enveloped DNA viruses that mainly cause proliferative lesions in the skin and mucosa of humans or animals. Papillomaviruses of different species have similar morphological characteristics. They are usually icosahedrons with a diameter of 52-60 nm. The core is a single copy of viral genomic DNA, and the shell is composed of the major coat protein L1 and the minor coat protein L2. Five L1 protein molecules aggregate to form a pentameric shell, and the viral shell is composed of 72 shell particles assembled in an icosahedral manner with T = 7.
Up to now, three HPV vaccine varieties based on the formation of virus-like particles (VLPs) by recombinant L1 coat protein have been launched worldwide, including the GlaxoSmithKline's bivalent HPV16/18 vaccine Cervarix as well as the quadrivalent HPV vaccine Gardasil and 9-valent HPV vaccine Gardasil9 of Merck & Co., Inc.
The HPV vaccine series products of Jiangsu Rec-Biotechnology Co., Ltd. include: 9-valent HPV vaccine (HPV types-6/11/16/18/31/33/45/52/58), bivalent HPV16/18 vaccine and bivalent HPV6/11 vaccine, all of which are currently in clinical trials. Among them, the 9-valent HPV vaccine has entered phase III clinical trial.