Bio-Bridge Science completes major construction of vaccine facility in China

US biotechnology firm Bio-Bridge Science, whose ambition is to develop an HIV vaccine, has finished major construction of a good manufacturing practice (GMP) research and manufacturing facility in Beijing.

The company will use the $3m (€2.4m) facility as a research and production environment for its vaccine products as well as pre-clinical and clinical trials.

These products include its HIV vaccine, HIV-PV Vaccine I, which is now completing pre-clinical trials, and vaccines for human papillomavirus infection and mucosal tumors, such as colonic and cervical cancers.

Because HIV infection occurs through the mucosal surface and infected cells also reside in the intestinal mucosa, intestinal mucosal immune responses to HIV are very important for controlling the infection.

Bio-Bridge's HIV vaccine is designed to induce both mucosal and systemic HIV-specific neutralising antibodies and cytotoxic T lymphocytes, claiming to be the ideal vaccine.

The company's strategy is to develop, test and obtain regulatory approval for HIV-PV Vaccine I in China first and then in the United States and Japan.

"We develop the vaccines in China because the cost is very low, we estimate it to be below 10 per cent of that in the US," Bio-Bridge Science CEO Liang Qiao told In-PharmaTechnologist.com.

"The facility may be used for small scale production, but once we get approval from China's State Food and Drug Administration (SFDA), we will expand the facility and we expect that this expansion will cost an additional $3m."

The facility already completed encompasses an area 2,200 of square metres, which includes the main facility, where research and production will take place.

The research area consists of an 815 square metre clean air surface area, which includes a 470 square metre 100,000 purity grade clean air environment, and a 345 square metre 10,000 purity grade clean air environment.

There will also be several 100 purity grade clean air environments within the 10,000 purity grade area, while the facility also includes a 750 square metre general working area and a 435 square metre electricity and water area.

The interior and exterior construction was completed according to GMP requirements, though construction of the high and low voltage electricity and installation of steam equipment is still taking place with local suppliers.

Bio-Bridge has licensed its vaccine technology, which is based on the production of papilloma pseudovirus, in China, the US and Japan.

Human papilloma or bovine papilloma pseudovirus is made by disrupting their virus-like particles, mixing them with plasmids or DNA vaccine, and reassembling them into pseudoviruses, virus-like particles with plasmids inside.

These pseudoviruses do not cause any disease and thus can be applied in gene therapy or used as a vaccine or an adjuvant.

The gene of interest can be inserted into a plasmid that is then packaged into virus-like particles which also can be modified to carry antigens of interest.

Oral administration of the pseudovirus will deliver the genes or antigens to intestinal mucosal, systemic lymphoid tissues, and mucosal epithelium.

The pseudovirus is different from other vaccines or gene-delivery vectors because most of them can only be injected subcutaneously or intramuscularly, but can't be given orally.

Moreover, most of the vaccines can induce only systemic immune responses, but not mucosal immune responses.

Because many pathogens are transmitted through mucosa, this pseudovirus can induce effective immune responses to prevent and to treat mucosal infections caused by pathogens.

These pathogens include bacteria such as salmonella and viruses such as HIV.

In addition, this pseudo-virus can be used to induce immune responses to treat tumors, in particular, mucosal tumors such as cervical cancer and colon cancer.

This pseudovirus also induces much stronger immune responses than DNA vaccines in addition to its advantage as a delivery vector to mucosa.

Bio-Bridge expects its therapeutic HIV-PV Vaccine I will be available in China in 2008 and its preventative HIV-PV Vaccine I will be available in approximately 2011.