Nose Spray Vaccines Could Quash COVID Virus Variants

The relentless evolution of the COVID-causing coronavirus has taken a bit of the shine off the vaccines developed during the first year of the pandemic. Versions of the virus that now dominate circulationOmicron and its subvariants—are more transmissible and adept at evading the body’s immune defenses than its original form. The current shots to the arm can still prevent serious illness, but their ability to ward off infection completely has been diminished. And part of the reason may be the location of the jabs, which some scientists now want to change.

To block infections entirely, scientists want to deliver inoculations to the site where the virus first makes contact: the nose. People could simply spray the vaccines up their nostrils at home, making the preparation much easier to administer. There are eight of these nasal vaccines in clinical development now and three in phase 3 clinical trials, where they are being tested in large groups of people. But making these vaccines has proven to be slow going because of the challenges of creating formulations for this unfamiliar route that are both safe and effective.

What could be most important about nasal vaccines is their ability to awaken a powerful bodily defender known as mucosal immunity, something largely untapped by the standard shots. The mucosal system relies on specialized cells and antibodies within the mucus-rich lining of the nose and other parts of our airways, as well as the gut. These elements move fast and arrive first, stopping the virus, SARS-CoV-2, before it can create a deep infection. “We are dealing with a different threat than we were in 2020,” says Akiko Iwasaki, an immunologist at Yale University. “If we want to contain the spread of the virus, the only way to do that is through mucosal immunity.

Iwasaki is leading one of several research groups in the U.S. and elsewhere that are working on nasal vaccines. Some of the sprays encapsulate the coronavirusspike proteins—the prominent molecule that the virus uses to bind to human cells—into tiny droplets that can be puffed into the sinuses. Others add the gene for the spike to harmless versions of common viruses, such as adenoviruses, and use the defanged virus to deliver the gene into nasal tissue. Still others rely on synthetically bioengineered SARS-CoV-2 converted into a weakened form known as a live attenuated vaccine.

Sourc: https://www.scientificamerican.com/

Pfizer-BioNTech begin Omicron vaccine trial

Pfizer and BioNTech have begun enrollment for a clinical trial to test the safety and immune response of their Omicron-specific Covid-19 vaccine in adults aged up to 55, the companies announced in a statement. The pharmaceutical giant could be ready to file for regulatory approval of the shot by March.

The company’s head of vaccine research Kathrin Jansen underscored that current data showed that boosters against the original Covid strain continued to protect against severe outcomes with Omicron. Still she recognizes the need to be prepared in the event this protection wanes over time and to potentially help address Omicron and new variants in the future.”

This study is part of our science-based approach to develop a variant-based vaccine that achieves a similar level of protection against Omicron as it did with earlier variants but longer duration of protection.”

The trial will involve 1,420 people aged 18-55. It did not include people older than 55 because the goal of the study was to examine the immune response of participants dosed, rather than estimate vaccine efficacy. The trial is taking place across the United States and South Africa, and the first participant was dosed in North Carolina. The volunteers are split into three groups. The first involves people who previously received two doses of the current Pfizer-BioNTech vaccine 90-180 days prior to enrollment, and will receive one or two doses of the Omicron vaccine. The second will be people who got three doses of the current vaccine 90-180 days prior to the study and will receive either another dose of the original shot or an Omicron-specific vaccine. The third and final group are people who have never previously received a Covid vaccine, and will receive three doses of the Omicron-specific vaccine.

The Pfizer-BioNTech vaccine was the first Covid shot to be authorized in the West, in December 2020.

Source: https://www.france24.com/

British Data Suggests Lower Hospitalisation Rate for Omicron Covid-19 Variant

Omicron is associated with a two-thirds reduction in the risk of Covid-19 hospitalisation. The preliminary studies — one paper from Scotland and the other from England — were cautiously welcomed by experts, who nonetheless stressed that any advantage in milder outcomes could still be negated by the new strain’s heightened infectiousness, which may still lead to more overall severe cases.

We’re saying that this is qualified good news — qualified because these are early observations, they are statistically significant, and we are showing a reduced risk of hospitalisations,” Jim McMenamin, a co-author of the Scottish research, told reporters on a call.

The Scottish paper examined Covid cases recorded in November and December, and grouped them by cases caused by Delta against those caused by Omicron. It found that “Omicron is associated with a two-thirds reduction in the risk of Covid-19 hospitalisation when compared to Delta,” while also showing that a booster vaccine offered substantial additional protection against symptomatic infection.

https://www.france24.com/

Omicron: two doses of Pfizer offer 70% protection against hospitalisation

Pfizer-BioNTech’s COVID-19 vaccine has been less effective in South Africa at keeping people infected with the virus out of hospital since the Omicron variant emerged last month, a real-world study published on Tuesday showed.

Between Nov. 15 and Dec. 7, people who had received two doses of the shot had a 70% chance of avoiding hospitalisation, down from 93% during the previous wave of Delta infections, the study showed. When it came to avoiding infection altogether, the study by South Africa’s largest private health insurance administrator, Discovery Health, showed that protection against catching COVID-19 had slumped to 33% from 80% previously.

The findings from the real-world analysis are some of the first about the protection vaccines offer against Omicron outside of laboratory studies, which have so far shown a reduced ability to neutralise the virus.

Source: https://www.reuters.com/

Boris Johnson: UK faces ‘tidal wave’ of omicron cases

Prime Minister Boris Johnson warned Sunday that Britain faces a “tidal wave” of infections from the omicron coronavirus variant, and announced a huge increase in booster vaccinations to strengthen defenses against it. In a televised statement, Johnson said everyone age 18 and older will be offered a third shot of vaccine by the end of this month in response to the omicronemergency.” The previous target was the end of January.

He said cases of the highly transmissible variant are doubling every two to three days in Britain, and “there is a tidal wave of omicron coming.”

And I’m afraid it is now clear that two doses of vaccine are simply not enough to give the level of protection we all need,” Johnson said. “But the good news is that our scientists are confident that with a third dose – a booster dose – we can all bring our level of protection back up.”

He announced a “national mission” to deliver booster vaccines, with pop-up vaccination centers and seven-day-a-week getting extra support from teams of military planners and thousands of volunteer vaccinators. Johnson’s Dec. 31 target applies to England. The other parts of the U.K. — Scotland, Wales and Northern Ireland — are also expected to speed up their vaccination campaigns.

The U.K. Health Security Agency says existing vaccines appear less effective in preventing symptomatic infections in people exposed to omicron, though preliminary data show that effectiveness appears to rise to between 70% and 75% after a third vaccine dose.

Source: https://www.startribune.com/