Tag: COVID vaccine

Categories : COVIDTags :

Moderna Narrowly Beats Pfizer in Effectiveness

On By ModernMedia
Image of a syringe for vaccination
Photo by Mika Baumeister on Unsplash

In the first head-to-head comparison of the effectiveness of the Pfizer-BioNTech and Moderna COVID vaccines, researchers examined the electronic health records of veterans who had received each vaccine and found Moderna to be slightly more effective.

The Moderna vaccine’s increased level of protection included a 21% lower risk of documented infection and 41% lower risk of hospitalisation, according to the research team, whose findings were published in the New England Journal of Medicine.

“Both vaccines are incredibly effective, with only rare breakthrough cases,” said Dr J.P. Casas, a member of the research team. “But regardless of the predominant strain – Alpha earlier and then Delta later – Moderna was shown to be slightly more effective.”

Researchers designed their comparative effectiveness study to address the previously unanswered question of which of the two mRNA vaccines is more effective. Effectiveness outcomes were: documented COVID, symptomatic disease, hospitalisation, ICU admission, and death. The investigators drew on the database of US veterans who received one of the two COVID vaccines between early January 2021 and mid-May 2021.

As initially designed, the research focused on the Alpha variant that predominated at the time. The study matched 219 842 recipients of the Pfizer vaccine to the same number of recipients of the Moderna vaccine. The two groups were matched based on a variety of clinical and demographic factors that could affect outcomes.

Over the study’s 24-week follow-up period, the estimated risk of documented infection was 4.52 events per 1000 people in the Moderna vaccine group and 5.75 per 1000 in the Pfizer group, an excess of 1.23 cases per 1000. The investigators also observed smaller excesses of symptomatic COVID (0.44 events), hospitalisation (0.55 events), ICU admission (0.10 events), and death (0.02 events) per 1000 people in the Pfizer group relative to the Moderna group.

This pattern of a lower risk for Moderna held up when Delta was the main strain. In this comparison, excess risk of documented infection over 12 weeks was 6.54 events per 1000 people for the Pfizer vaccine, compared to Moderna. Given the shorter time frame available for this supplementary research, infection was the only outcome researchers analyzed. Also, the estimates were considered less precise because a smaller number of individuals were eligible for this analysis.

Randomised trials comparing the mRNA vaccines against placebos had previously shown both vaccines to be very effective against symptomatic COVID infection (95% effectiveness for Pfizer-BioNTech, 94% for Moderna), borne out by real-world vaccine use.

“Given the high effectiveness of both the Moderna and Pfizer vaccines, confirmed by our study, either one is recommended to any individual offered a choice between the two,” said first author Dr Barbra A. Dickerman. “However, while the estimated differences in effectiveness were small on an absolute scale, they may be meaningful when considering the large population scale at which these vaccines are deployed. This information may be helpful for larger decision-making bodies.”

The massive Veteran Association records system supported a very large sample size. This, in turn, allowed the study to identify even small differences in effectiveness between the Pfizer and Moderna vaccines. The researchers used a methodology known as causal inference to mirror a gold standard randomised trial as closely as possible. Causal inference is a type of data analysis that helps researchers draw firm conclusions about cause and effect.

Using the VA database, vaccine recipients were closely matched on age, sex, race, geographic location, and other attributes that could affect COVID-related outcomes.

“After this careful matching, we found that the two vaccine groups were extremely similar in terms of variables with respect to an extensive set of demographic, geographic, and health-related attributes,” Dr Dickerman said. “This allowed our observational analysis to produce exceptionally credible results during a global emergency, when answers are needed fast and randomised trials can be impractical.”

As the global pandemic continues to unfold, the research team is working on answers relating to the comparative safety, versus effectiveness, of the Pfizer and Moderna vaccines. Dr Dickerman characterises comparative safety as an “additional piece of the puzzle to support vaccine decision-making.”

Even beyond this analysis, further evaluation of the vaccines’ comparative effectiveness and safety is needed, the authors concluded. Meanwhile, given the evidence at hand, the authors concluded about the Pfizer and Moderna vaccines considered in their study, “Given the high effectiveness and safety profile of both mRNA vaccines, either one is strongly recommended.”

Source: EurekAlert!

Categories : COVIDTags :

Six Different Booster Vaccines Found to be Safe and Effective

On By ModernMedia
Image by Ivan Diaz on Unsplash

The first randomised trial of COVID boosters, published in The Lancet, has shown that six are safe and provoke strong immune responses. Participants have previously received a two-dose course of ChAdOx1-nCov19 (Oxford–AstraZeneca [ChAd]) or BNT162b2 (Pfizer-BioNTech [BNT]). The announcement comes just as the Omicron variant is beginning to spread around the world.

ChAd has now been deployed in more than 180 countries and BNT in more than 145 countries. Several studies show that two doses of ChAd and BNT confer 79% and 90% protection, respectively, against hospitalisation and death after six months. However, protection against COVID infection wanes in time, which has led to the consideration of boosters. However, there are currently little data on the comparative safety of COVID vaccines, and the immune responses they stimulate, when given as a third dose.

The COV-BOOST study looked at safety, immune response (immunogenicity) and side-effects (reactogenicity) of seven vaccines when used as a third booster jab. The vaccines studied were ChAd, BNT, NVX-CoV2373 (Novavax [NVX]), Ad26.COV2.S (Janssen [Ad26]), Moderna [mRNA1273], VLA2001 (Valneva [VLA]), and CVnCov (Curevac [CVn]).

“The side effect data show all seven vaccines are safe to use as third doses, with acceptable levels of inflammatory side effects like injection site pain, muscle soreness, fatigue. Whilst all boosted spike protein immunogenicity after two doses of AstraZeneca, only AstraZeneca, Pfizer-BioNTech, Moderna, Novavax, Janssen and Curevac did so after two doses of Pfizer-BioNTech”, commented Professor Saul Faust, trial lead.

“It’s really encouraging that a wide range of vaccines, using different technologies, show benefits as a third dose to either AstraZeneca or Pfizer-BioNTech. That gives confidence and flexibility in developing booster programmes here in the UK and globally, with other factors like supply chain and logistics also in play”, added Prof Faust.

“It’s important to note that these results relate only to these vaccines as boosters to the two primary vaccinations, and to the immune response they drive at 28 days. Further work will generate data at three months and one year after people have received their boosters, which will provide insights into their impact on long-term protection and immunological memory. We are also studying two of the vaccines in people who had a later third dose after 7-8 months although results will not be available until the new year.”

A randomised, phase 2 trial of seven booster vaccines was conducted, with the third doses given 10-12 weeks after initial two-dose courses of ChAd or BNT. The trial involved 2878 healthy participants between June 1st and June 30th 2021. Participants had received their first doses of ChAd or BNT in December 2020, January or February 2021, and second doses at least 70 days before enrolment for ChAd and at least 84 days for BNT. About half of participants received two doses of ChAd and half two doses of BNT. The control vaccine used was a meningococcal conjugate vaccine (MenACWY).

Participants were aged 30 or older, roughly half of whom were 70 or older. The average age of participants who received ChAd was 53 years in the younger age group and 76 years in the older age group. Average ages for BNT were 51 and 78 years, respectively.

Thirteen experimental and control arms of the trial (seven vaccines plus three at half dose and three control arms) were split into three participant groups. Group A received NVX, half dose NVX, ChAd, or a control. Group B received BNT, VLA, half dose VLA, Ad26 or a control. Group C received Moderna, CVn (development of which was halted in October 2021), half dose BNT, or a control.

Primary outcomes were adverse effects seven days after receiving a booster, and levels of antibodies targeting the SARS-CoV-2 Spike protein after 28 days, compared to controls. Secondary outcomes included the response of T cells to wild type, Alpha, Beta, and Delta variants. 

Increases in anti-spike protein antibody levels after 28 days varied across the vaccines. After two doses of ChAd these ranged from 1.8 times higher to 32.3 times higher according to the booster vaccine used. Following two doses of BNT, the range was 1.3 times higher to 11.5 times higher. Significant T-cell responses were reported in several combinations.

At 28 days, all booster results were similar for participants aged 30-69 years and those aged 70 years or older. Boost ratios should be interpreted with caution, the authors caution, since they relate to immunogenicity rather than protection against disease, and the relationship between antibody levels at day 28 and long-term protection and immunological memory is unknown.

Reactions to all seven vaccines were similar, with fatigue, headache, and injection site pain most often reported. These were more commonly reported by those aged 30-69. 912 of the 2878 participants experienced a total of 1036 adverse events, 24 of which were severe.

Source: EurekAlert!

Categories : COVID VaccinesTags :

Mechanism Behind AstraZeneca and J&J Vaccine Blood Clots Found

On By ModernMedia
A cloud of platelet factor 4 proteins interacting with the electrostatic surface of the Oxford vaccine, as seen through the computational microscope.
Credit: Chun Kit Chan, Arizona State University

An international team of scientists believe they may have found a molecular mechanism behind the extremely rare blood clots linked to adenovirus vaccines.

Scientists led by a team from Arizona State University, Cardiff University and others worked with AstraZeneca to investigate vaccine-induced immune thrombotic thrombocytopenia (VITT), also known as thrombosis with thrombocytopenia syndrome (TTS), a life-threatening condition seen in a very small number of people after receiving the Oxford-AstraZeneca or Johnson & Johnson vaccines.

“The mechanism which results in this condition, termed vaccine-induced immune thrombotic thrombocytopenia (VITT), was unknown,” said Abhishek Singharoy, an Arizona State University scientist and corresponding author of the study who teamed up to lead an international effort to tease out the details. 

Together, the team worked to solve the structural biology of the vaccine, and see the molecular details that may be at play, utilising state-of-the cryo-EM technology to analyse the AstraZeneca vaccine in minute detail. They sought to understand whether the ultra-rare side effect could be linked to the viral vector which is used in many vaccines, including those from Oxford/AstraZeneca and Johnson & Johnson.

Their findings suggest it is the viral vector – in this case, an adenovirus used to shuttle the coronavirus’ genetic material into cells – and the way it binds to platelet factor 4 (PF4) once injected that could be the potential mechanism.

In very rare cases, the scientists suggest, the viral vector may enter the bloodstream and bind to PF4, where the immune system then views this complex as foreign. They believe this misplaced immunity could result in the release of antibodies against PF4, which bind to and activate platelets, leading to clustering and blood clotting.

“It’s really critical to fully investigate the vector-host interactions of the vaccine at a mechanistic level,” said Singharoy. “This will assist in understanding both how the vaccine generates immunity, and how it may lead to any rare adverse events, such as VITT.”

Their findings were published in Science Advances.

Adenovirus expert Professor Alan Parker said: “VITT only happens in extremely rare cases because a chain of complex events needs to take place to trigger this ultra-rare side effect. Our data confirms PF4 can bind to adenoviruses, an important step in unravelling the mechanism underlying VITT. Establishing a mechanism could help to prevent and treat this disorder.”

“We hope our findings can be used to better understand the rare side effects of these new vaccines – and potentially to design new and improved vaccines to turn the tide on this global pandemic.”

The AstraZeneca and Johnson & Johnson vaccines both use an adenovirus to carry SARS-CoV-2 Spike proteins to trigger an immune response.

Since VITT was seen in both vaccines, scientists wondered whether the viral vector was involved. Additionally, neither the Moderna nor Pfizer vaccines, both mRNA vaccines, showed this effect.

Using cryo-EM technology to flash-freeze preparations of ChAdOx1, the adenovirus used in the AstraZeneca vaccine, they produce microscopic images of the vaccine components.

They were then able to view the viral capsid structure and other critical proteins that allow entry of the virus into the cell.

In particular, the team outlined the details for the structure and receptor of ChAdOx1, which is adapted from chimpanzee adenovirus Y25 – and how it interacts with PF4. They believe it is this specific interaction – and how it is then presented to the immune system – that could cuase the immune system to see it as foreign and release antibodies against this self-protein.

The research team also used computational models to show that one of the ways the two molecules tightly bind is via electrostatic interactions. The group showed that ChAdOx1 is mostly electronegative, attracting other positively charged molecules to its surface.

First author Dr Alexander Baker said: “We found that ChAdOx1 has a strong negative charge. This means the viral vector can act like a magnet and attract proteins with the opposite, positive charge, like PF4.” Baker is a member of ASU’s Biodesign Center for Applied Structural Discovery and an Honorary Research Fellow at Cardiff University School of Medicine.

“We then found that PF4 is just the right size and shape that when it gets close to ChAdOx1 it could bind in between the negatively charged parts of ChAdOx1’s surface, called hexons.”

The research team are hopeful that armed with a better understanding of what may be causing rare VITT they can provide further insights into how vaccines and other therapies, which rely on the same technology, might be altered in the development of the next generation vaccines and therapies.

“With a better understanding of the mechanism by which PF4 and adenoviruses interact there is an opportunity to engineer the shell of the vaccine, the capsid, to prevent this interaction with PF4. Modifying ChAdOx1 to reduce the negative charge may reduce the chance of causing thrombosis with thrombocytopenia syndrome,” said Baker.

The team likened it to the ‘two birds, one stone’ effect. The key contacts of individual amino acids that are essential to the capsid protein’s proteins interaction with PF4 can removed or substituted.

“The modification of the ChAdOx1 hexons to reduce their electronegativity may solve two problems simultaneously: reduce the propensity to cause VITT to even lower levels, and reduce the levels of pre-existing immunity, thus helping to maximize the opportunity to induce robust immune responses, said Singharoy.”

Source: EurekAlert!

Categories : COVIDTags :

Pharma Giants Draw Their Plans Against Omicron

On By ModernMedia
Image by Ivan Diaz on Unsplash

As world leaders seek to reassure an anxious world about the emergence of Omicron, Moderna’s CEO believes that vaccines will not have the same level of effectiveness against the new variant. Meanwhile, other major vaccine developers such as Oxford University maintain that it is still too early as yet to draw conclusions, and existing vaccines can be updated in a matter of months.

In an interview with the Financial Times, Moderna CEO Stéphane Bancel said that “in no world” would vaccines protect against Omicron at the same level as they did against Delta. He added that he thought it would be “material drop”, though data was still to come. However, the scientists he spoke to had all said “‘This is not going to be good’.” This is because 32 of the variant’s 50 mutations are on the Spike protein, which current vaccines are designed to target.

He noted the reduced effectiveness of existing vaccines against Delta, saying that scientists had not expected such a high level of mutation to emerge for another two to three years. His comments come in stark contrast to others who stress that there is no information yet to suggest that Omicron is any more serious than previous variants, or that vaccines are less effective against it.

Oxford University released a statement saying they were monitoring the situation, but stood ready to produce a new vaccine if necessary.

“Despite the appearance of new variants over the past year, vaccines have continued to provide very high levels of protection against severe disease and there is no evidence so far that Omicron is any different.

“However, we have the necessary tools and processes in place for rapid development of an updated COVID vaccine if it should be necessary.”

Pfizer’s CEO Albert Bourla said in an interview with CNBC that his company had already started work on an updated vaccine, which would be ready in 100 days.

In the Netherlands, scientists from the country’s National Institute of Public Health said that they had detected Omicron on flights that had arrived from Southern Africa before the official announcement of the discovery by South Africa. The country is now trying to locate and isolate some 5000 individuals who arrived in the country from the region. 

Categories : COVIDTags :

Europe to Return Millions of Locally-filled J&J Vaccines

On By ModernMedia

The European Union has agreed to return millions of COVID vaccines doses partially produced in South Africa back to the African continent.

South Africa’s Aspen Pharmacare operates the plant that is partially producing Johnson & Johnson vaccines, where vaccine substance from Europe is sent to be bottled and shipped.

The plant is supposed to produce 400 million doses for the AU’s African Vaccine Acquisition Trust through 2022, to be purchased by African nations using World Bank financing. Shipments started in August, with 6.4 million doses delivered to countries, but they have been limited due to the manufacturing plant’s production capacity.

The announcement came as Africa struggles to immunise its population against COVID, partly due to a lack of supply resulting from wealthier countries buying up most vaccines, and also from widespread vaccine hesitancy. 

“All the vaccines produced at Aspen will stay in Africa and be distributed to Africa,” said Strive Masiyiwa, special African Union envoy. “This issue has been corrected and corrected in a very positive way.”

The announcement came after a meeting in Berlin between South African President Cyril Ramaphosa and European Commission President Ursula Von der Leyen, he said, adding that the first supplies were expected this month.

“In addition, the Europeans committed to give us 200 million doses before the end of December,” Masiyiwa said at the briefing by the Africa Centres for Disease Control and Prevention.

About 2.93% of people who have been fully immunised against COVID, said Africa CDC director John Nkengasong. The World Health Organization meanwhile warned that eight out of 10 African countries were likely to fall short of the “crucial” goal of vaccinating the most vulnerable 10% of their populations against COVID by the end of the month.

Source: Eyewitness News

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Pfizer Vaccine Fully Approved in US

On By ModernMedia
Photo by Mat Napo on Unsplash

On Monday, the US Food and Drug administration approved the Pfizer/BioNTech COVID vaccine, the first vaccine against the novel coronavirus to receive full approval.

The vaccine, which will be marketed as Comirnaty, can be used for individuals ages 16 and older for COVID prevention. However, the vaccine is still under emergency use authorisation (EUA) for adolescents ages 12-15, the agency said.

FDA Acting Commissioner, Janet Woodcock, MD, said in a statement: “While this and other vaccines have met the FDA’s rigorous, scientific standards for emergency use authorisation, as the first FDA-approved COVID vaccine, the public can be very confident that this vaccine meets the high standards for safety, effectiveness, and manufacturing quality the FDA requires of an approved product.”

At a media briefing, Peter Marks, MD, PhD, the director for the Center for Biologics Evaluation and Research at FDA, detailed the meticulous process used for conducting a review of a biologics license application for full approval, including invidivual analysis of adverse events.

Since 11 December, 2020, the vaccine has been under an EUA for individuals ages 16 and older. Evidence for the full approval comes from expanded phase III trial safety and efficacy data released by the manufacturer this April. An analysis of 927 confirmed cases in the trial’s 44 000 participants found that 7 days after the second dose, Comirnaty had a 91.3% efficacy against symptomatic COVID through 6 months.

More than half of the participants had over 4 months of safety data, including 12 000 people who were followed up through 6 months. Injection site pain, fatigue, headache, muscle or joint pain, and fever were the most common adverse events. A slight increase in risk for myocarditis and pericarditis up to 7 days after the second dose was noted, particularly in males under 40 (peaking in ages 12-17), but symptoms resolved completely.

Trial data was collected before the Delta variant became the dominant strain in the US, Dr Marks noted, Israeli “real world” suggest the vaccine still retains effectiveness but wanes. This is something the agency will follow. 

Former FDA commissioner Dr. Mark McClellan, who now directs the Duke-Margolis Center for Health Policy, spoke to the media about the approval, saying surveys showed that it will help sway vaccine holdouts.

“I do think it will make a difference. Maybe not a large number of people running out and getting a vaccine today. At this point we’ve got a little bit over 70 percent of Americans who are eligible for the vaccine have gotten at least one dose. That’s about 87 million Americans who are eligible who haven’t. Out of those, according to some recent surveys, about 30 percent say the full approval of the Pfizer vaccine would make a difference in their decisions.”

Source: MedPage Today

Categories : COVIDTags :

New Study Sheds More Light on AstraZeneca Blood Clots

On By ModernMedia
Credit: National Institutes of Health

A UK study has furthered the understanding of the novel blood-clotting condition associated with the Oxford/AstraZeneca vaccine.

Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is characterised by a blockage of veins and a marked platelet reduction. The rare condition was first identified in the UK by Professor Marie Scully (University College of London Institute of Cardiovascular Science), also a Consultant Haematologist at UCLH, and Dr Will Lester from University Hospitals Birmingham NHS Foundation Trust.

In a paper published in the New England Journal of Medicine (NEJM), the first 220 cases of definite and probable VITT in the UK are detailed.

The cases were presented by 182 consultant haematologists, and builds on understanding about the condition outlined in an April 2021 NEJM paper led by Professor Scully.

Meanwhile, a study led by Dr Richard Perry (UCL Queen Square Institute of Neurology and UCLH) published in the Lancet earlier this month provided the most detailed observations so far of cases of cerebral venous thrombosis (CVT). one of the commonest and severest manifestations of VITT.

The overall mortality rate of those presenting to hospitals with definite or probable VITT was 23%, the paper reported. The condition almost entirely manifested between five and 30 days after their first vaccination, with no sex differences seen, and no predisposing prior medical conditions.

The chances of death increased significantly the lower the platelet count and the greater the activation of the blood clotting system, increasing to 73% in patients with a very low platelet count and intracranial haemorrhage following blood clots in the brain.

Overall, 41% of patients had no previous medical diagnoses and 85% were less than 60 years old. Overall incidence in individuals under 50 was estimated to be 1 in 50 000 – in line with reports from other countries.

Though optimal treatment was still uncertain, it was being continually refined in real time, the researchers wrote. For instance, the introduction of the use of plasma exchange in the most severe cases has led to survival rates that were significantly better than would be predicted based on baseline characteristics.

The research adds to evidence for use of non-heparin-based blood thinners to tackle blood clotting in cases of VITT, and that use of intravenous immunoglobin was associated with better outcomes.

Professor Scully said: “As a new condition we are still learning about how best to diagnose and manage VITT, but as time goes on, we have been able to refine our treatment approaches and improve rates of survival and chance of recovery. This continuous learning in real time has been made possible thanks to collaboration between colleagues across the UK.”

Lead author Dr Sue Pavord, at Oxford University Hospitals NHS Foundation Trust, said: “We have worked relentlessly to understand and manage this new condition, so that the hugely successful vaccine roll out can continue, which is the most viable solution to the global pandemic.”

Source: University College London

Categories : COVID VaccinesTags :

Second J&J Dose Needed for Delta Variant

On By ModernMedia
Photo by Ivan Diaz on Unsplash

Johnson & Johnson’s COVID vaccine is much less effective against the Delta and Lambda variants than against the original wild-type virus, according to a new study posted on the BioRxiv preprint server on Tuesday.

Though a cause for concern, the results come from in vitro tests, and may not reflect the real world vaccine performance. However, the authors said this adds to evidence that the 13 million people inoculated with the J&J vaccine may need a second dose, preferably an mRNA vaccine, the authors said.
The findings, which are still to be peer reviewed, are however consistent with observations that a single dose of the AstraZeneca vaccine, which is similar to the J&J one, shows only about 33 percent efficacy against developing symptoms with the Delta variant.

“The message that we wanted to give was not that people shouldn’t get the J&J vaccine, but we hope that in the future, it will be boosted with either another dose of  J&J or a boost with Pfizer or Moderna,” said study leader Nathaniel Landau, a virologist at NYU’s Grossman School of Medicine.

Other experts said the results are what they would have expected, because all of the vaccines seem to work better when given in two doses. “I have always thought, and often said, that the  J&J vaccine is a two-dose vaccine,” said John Moore, a virologist at Weill Cornell Medicine in New York.

Dr Moore pointed to several studies in monkeys and people that have shown greater efficacy with two doses of the J&J vaccine, compared with one dose. The new study was particularly credible, he said, because it was published by a team not linked to any vaccine manufacturer.

But the data from the new study “do not speak to the full nature of immune protection,” said Seema Kumar, a spokeswoman for J&J. “Studies sponsored by the company indicate that the vaccine “generated strong, persistent activity against the rapidly spreading Delta variant,” she said.

The Delta variant is the most transmissible of the SARS-CoV-2 variants, and has become dominant in South Africa. 

Several studies have suggested that the mRNA vaccines made by Pfizer-BioNTech and Moderna will maintain their efficacy against the coronavirus, including all variants identified so far. One recent study showed, for example, that the vaccines trigger a persistent immune reaction in the body that may protect against the coronavirus for years. The J&J vaccine is newer, and has had fewer studies.

The J&J vaccine has had reports of rare blood clots and extremely rare neurological disorders, as well as problems with contamination at a US manufacturing plant. This is still not as bad as the disastrous news that the AstraZeneca vaccine was virtually ineffective against the Beta variant which was then the dominant strain in South Africa.

Small studies by J&J affiliated researchers suggested that the vaccine was only slightly less effective against the Delta variant than against the wild-type virus, and that antibodies stimulated by the vaccine grew in strength over eight months.

Dr Dan Barouch, a virologist at Beth Israel Deaconess Medical Center in Boston said it was important to consider the vaccine’s strength over time.

“Fundamentally I don’t see that there’s any discordance,” he said. “The question is that of kinetics, it’s not just magnitude, because immune responses are not static over time.” The new study also did not consider other components of immune defence, he added.

Dr Landau and his colleagues had compared blood samples taken from 17 people who had two doses of an mRNA vaccine and 10 who had one J&J vaccine dose.

The  J&J vaccine started out with a lower efficacy than the mRNA vaccines and showed a bigger drop in efficacy against the Delta and Lambda variants. “The lower baseline means that what’s left to counter Delta is very weak,” Dr Moore said. “That is a substantial concern.”

Very few vaccines are given as a single dose, because the second dose is needed to amp up antibody levels, noted Akiko Iwasaki, an immunologist at Yale University. People who were inoculated with the J&J vaccine “are relying on that primary response to maintain high levels of antibodies, which is difficult, especially against the variants,” she said.

Boosting immunity with a second dose should raise the antibody levels high enough to counter the variants, she said.

Source: New York Times

Categories : COVID Diseases, Syndromes and ConditionsTags :

A Report of Two Sequential Cases of Facial Palsy after COVID Vaccines

On By ModernMedia

The case of a patient who experienced two facial palsies, both immediately after receiving the Pfizer-BioNTech vaccine, strongly suggests that they are linked to the vaccine, wrote in the journal BMJ Case Reports.

The case report of two separate unilateral facial nerve palsies, where muscles on one side of the face become weak or paralysed, occurring shortly after each dose of a COVID vaccine, is the first in medical literature.

“The occurrence of the episodes immediately after each vaccine dose strongly suggests that the Bell’s palsy was attributed to the Pfizer-BioNTech vaccine, although a causal relationship cannot be established,” the authors said.

Single episodes of unilateral facial nerve palsies were reported in the initial clinical trials of Pfizer-BioNTech, Moderna and Oxford/Astra Zeneca and there have been subsequent case reports.

In phase 3 trials, four cases of facial palsy of unknown cause (Bell’s palsy) were reported in volunteers who received the Pfizer-BioNTech mRNA vaccine and none in the placebo group, and three cases were reported in volunteers who received the Moderna mRNA vaccine compared with one in the placebo group. Three cases of facial nerve palsy were also reported in volunteers who received the Oxford/AstraZeneca vaccine, and there were three cases in the placebo group.

This case report describes a 61-year-old Caucasian male with no previous history of facial nerve palsy who experienced an episode of Bell’s palsy on the right side of his face five hours after receiving his first dose of the Pfizer-BioNTech vaccine, and a more severe episode of Bell’s palsy on the left side of his face two days after receiving the second dose. The patient had a high BMI, hypertension, hypercholesterolaemia and type 2 diabetes.

After the first episode, the patient went to the emergency department, with incomplete eye closure and no forehead movement and was diagnosed with Bell’s palsy. Blood tests and a CT head scan revealed no pathologies and he was discharged with a course of steroids, and the right-sided facial nerve palsy completely resolved.

Two days after his second shot, he developed a more severe left-sided facial nerve palsy. The symptoms included dribbling, difficulty swallowing and again, incomplete left eye closure. He went to the emergency department, where he was again prescribed a course of steroids. He was also referred to an emergency Ear Nose and Throat clinic, which continued the steroids and referred him to ophthalmology.

The authors reported that the patient is almost back to normal. “The patient has been advised to discuss future mRNA vaccines with the GP on a case-by-case basis, taking into account risk versus benefit of having each vaccine,” they said.

Bell’s palsy is believed to be related to facial nerve inflammation and oedema from viral infection. In 2004 the inactivated intranasal influenza vaccine was shown to significantly increase the risk of Bell’s palsy and was discontinued. Increased incidence of Bell’s palsy has also been seen following administration of other influenza and meningococcal vaccines. The annual incidence is 15 to 20 per 100 000 and the lifetime risk is 1 in 60, with an 8% to 12% recurrence rate.

While most cases of Bell’s palsy recover on their own over time, the symptoms can cause significant temporary disability, affecting facial expression and eating and drinking. Risk factors for the condition include diabetes, obesity, hypertension, pregnancy, pre-eclampsia and upper respiratory disease.

Source: EurekAlert!

Categories : COVID VaccinesTags :

ImmunityBio COVID Booster Gets Go-ahead for South African Trials

On By ModernMedia
Photo by Mufid Majnun on Unsplash
Photo by Mufid Majnun on Unsplash

Immunotherapy company ImmunityBio has been authorised by the South Africa Health Products Regulatory Authority (SAHPRA) to proceed with the South Africa Sisonke T-Cell Universal Boost trial. 

The Phase 1/2/3 study, starting in the second third quarter of 2021, is designed to evaluate hAd5 Spike + Nucleocapsid (S+N) as a boost for South African healthcare workers previously vaccinated with an S (Spike)-only vaccine.

“With the virus continuing to spread, moving forward with this boost trial is crucial,” said Leonard Sender, MD, Chief Operating Officer of ImmunityBio. “We are encouraged by the preliminary safety findings in our ongoing Phase 1 studies in both the U.S. and South Africa. In addition, our U.S. data show that just a single prime subcutaneous vaccination with our COVID-19 vaccine candidate induces a 10-fold increase in T cell response—equivalent to T cell responses from patients previously infected with SARS-CoV-2. We have also shown that the T-cell responses are maintained against variants, which is critical to providing protection against this ever-changing virus.”

In the trial, the effect of combining vaccination by subcutaneous (SC) and sublingual (SL) routes will be assessed. This combination has the potential to deliver protection from the virus with a single injection followed by droplets placed under the tongue. Methods that do not require injection such as SL, intranasal, and oral capsule offer potential advantages depending on the participant’s needs or situation. Sublingual administration offers the most rapid absorption, while nasal spray or oral capsule delivery have the potential to provide mucosal immunity, which could reduce both the chance of infection and potential spread of the virus via the respiratory tract. The three non-injection formulations do not need a trained healthcare worker to administer them and are easier to transport and store. The SL and nasal routes of administration are also currently being tested in a separate Phase 1 trial in South Africa.

“The number of new cases in South Africa is frightening, particularly when you consider recent data suggesting currently available COVID-19 vaccines may not provide the immune memory needed to fend off infection from future variants. This highlights an urgent need for a boost dose that confers long-term protection by activating both antibodies and T cells, ” said Patrick Soon-Shiong, MD, Founder and Executive Chairman of ImmunityBio.

“Several peer-reviewed studies demonstrate that patients who have recovered from SARS-CoV in the 2003 outbreak possess long lasting memory T cells reactive to the nucleocapsid protein of SARS-CoV 17 years after infection. While antibodies block infection when present, T cells are vital for long-term immune memory. We are excited to begin this controlled, randomized trial of boosting a previously administered DNA-based viral vector vaccine with our own Ad5 dual-antigen S plus N vaccine to see if it can augment protection in participants who have received the S-based vaccine alone,” added Dr Soon-Shiong.

Source: BusinessWire