BEIJING, Sept. 26 (Xinhua) -- Chinese official pledged to optimize processes and spare no efforts in putting COVID-19 vaccines on market as early as possible while adhering to laws and regulations and ensuring safety and effectiveness.

The safety and effectiveness of the COVID-19 vaccines must comply with relative standards, pass the process validation of mass production and set up controllable quality standards, said Yang Sheng, an official with the National Medical Products Administration, at a press conference in Beijing on Friday.

Up till now, there have been 11 Chinese COVID-19 vaccines entering clinical trials, with four in phase-3 clinical trials.

The duration of phase-3 clinical trials depends on many factors including the number of participants and the speed of their participation, said Yang.

Facing the new virus of COVID-19, China quickly arranged five technical routes for vaccine development, said Wang Junzhi, an academician with the Chinese Academy of Engineering.

This is by virtue of the country's accumulation in vaccine development ability, technology and experience over the years, Wang said.

Chinese vaccine production enterprises have signed cooperative agreements with institutions from a number of countries to jointly implement phase-3 clinical trials in accordance with the laws and regulations.

Two inactivated COVID-19 vaccines developed by the China National Biotec Group (CNBG) are under phase-3 clinical trials in the Middle East, with more than 35,000 people inoculated, according to Wu Yuanbin, an official with the Ministry of Science and Technology.

The trials in the Middle East have so far shown good safety and no serious adverse reactions, Wu said.

Another inactivated COVID-19 vaccine developed by Sinovac Biotech Co., Ltd. is undergoing phase-3 clinical trials in some countries in South America and Southeast Asia in accordance with the laws, Wu said.

An adenovirus vector vaccine developed by the Institute of Military Medicine under the Academy of Military Sciences and CanSino Biologics Inc. was approved to conduct phase-3 clinical trials in some countries in Europe and Asia, Wu said.