History’s Seven Deadliest Plagues

CanSino Unveiled The World's First Inhalable Covid-19 Vaccine In China's Hainan

HAIKOU /China/, Nov. 17. /TASS/. China's pharmaceutical company CanSino Biologics Inc., presented the world's first inhalable Covid-19 vaccine at the 5th Hainan International Healthcare Industry Exhibition, the Hainan Daily reports. The vaccine was developed by the biotech company itself.

"The coronavirus mainly enters the human body through the cells of the mucous membrane of the respiratory tract. [The membrane's] immune function is of paramount importance," said Zhao Guojun, Deputy Sales Director of CanSino. "Creating a reliable immune response in the mucous membrane allows the virus to be destroyed before it affects the tissue."

The inhalable vaccine creates a kind of protective shield for the human respiratory system, he said. "It's effective in preventing the spread of infection," the deputy director added.

He assured that this type of vaccine causes the immune system to generate antibodies quicker than after getting the traditional shot. Zhao Guojun said it also lasts longer than conventional vaccination.

In February, the National Medical Products Administration (NMPA) of the People's Republic of China granted conditional approval for the sale of the CanSino inhalable vaccine on the Chinese market. It has already been widely used in the PRC. According to the manufacturer, the drug is not only safe and painless, but also highly effective.

The Hainan International Health Industry Exhibition is considered to be one of the key events of the province during the 14th Five-Year Plan period (2021-2025). It is an important platform for establishing partnerships between the southernmost Chinese region and other countries in the field of medicine. It has gradually shaped the world's perception of Hainan as an important regional center for high quality medical services.

China's CanSino Defends Coronavirus Vaccine Candidate After Experts Cast Doubt

SHANGHAI--China's CanSino Biologics Inc. Said on Wednesday that expert opinion on its high-profile coronavirus vaccine candidate should not be followed "blindly" without sufficient clinical trial data.

Scientists outside the company have expressed concern that the effectiveness of CanSino's candidate Ad5-nCoV, which is based on a common cold virus to which many people have been exposed, could be limited. They said existing antibodies against the common cold virus might undermine Ad5-nCoV.

"Vaccine development is a practice-based science, and we should not blindly follow experts," Zhu Tao, chief scientific officer, said during an investor conference.

He said there were instances in which vaccines created using methods doubted by experts had obtained regulatory approvals after clinical trials proved they worked.

No evidence showed that existing antibodies against the common cold could have a major adverse impact on Ad5-nCoV's ability to trigger antibodies against the novel coronavirus, Zhu said, citing results from 128 participants tested with a lower dose of the vaccine candidate in a mid-stage trial.

Ad5-nCoV, still in final-stage trials, has been approved for use in the Chinese military.

Vaccine companies normally have to collect data in large-scale, late-stage trials to obtain regulatory approval for mass use.

It is unscientific to compare the antibody levels generated by different vaccine candidates so far, because varied testing methods could distort results, Zhu said.

AstraZeneca Plc on Tuesday said it paused a late-stage trial of one of its leading experimental viral vector-based vaccine, which uses a technology similar to CanSino's, after an unexplained illness in a study participant.

The hiccup does not mean all viral-vector based experimental vaccines are risky, Zhu said, adding that it was not rare for clinical trials to be paused.

CanSino's shares were up 6% at HK$181.50 ($23.42) on Wednesday afternoon in Hong Kong.

First Published Data Backs CanSino's Inhaled COVID Vaccine

Early-stage clinical data with CanSino Biologics' inhaled COVID-19 vaccine show that it was able to stimulate neutralising antibodies against SARS-CoV-2 at a dose well below that required with intramuscular administration.

Published in The Lancet, a phase 1 study conducted in China showed that a two-dose regimen of aerosolised Ad5-nCoV was similar to that achieved with a single, intramuscular dose of the same vaccine.

Administration of the new version was painless and the regimen well tolerated in the phase 1 trial, write the authors of the study. It was also found to stimulate both neutralising antibodies and T cell responses – the latter is thought to play a role in recognising and killing infected cells and stimulating antiviral cytokines – after a single dose.

The study also hints that aerosol vaccination could trigger a higher ratio of neutralising antibodies to total antibodies than intramuscular vaccinations, and that a combination of an intramuscular first dose followed by an aerosol second may provide the best results overall.

The researchers acknowledge however that the study is small, so those hypotheses will have to be tested in ongoing phase 2 and 3 trials.

Ad5.NCoV is already approved in China and other countries around the world as a one-dose jab called Convidecia, and was shown to be around 66% protective in a clinical trial reported in February. CanSino moved the inhaled formulation into clinical testing in April.

While the current injected COVID-19 vaccines are effective, the majority of people around the world remain unvaccinated, and there remains a need for new options that are easy to administer.

In the case of Ad5-nCoV, the dose needed was 20% or 40% of that needed with the injected version, which could make supplies of the vaccine stretch further, and it needs standard refrigeration temperatures so is easy to store and ship.

The hope is that inhaled vaccines may also be more effective at stimulating mucosal immunity in the lungs, which provides a first line of defense against respiratory pathogens, and the researchers suggest their early data on antibody and cellular responses back up this hypothesis.

CanSino is working with the Beijing Institute of Biotechnology on the inhaled vaccine, which is delivered using a nebuliser.

Other groups are also working on alternative means of COVID-19 vaccine delivery, including UK's Imperial College London, which is running a small trial of its mRNA-based candidate and the AstraZeneca/Oxford University vaccine to see if they can be delivered to the lungs rather than by injection into the muscle.

Intranasal delivery is also being explore, although one front runner in this category – Altimmune – abandoned its candidate after finding weaker-than-expected immune responses in a phase 1 trial.

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