Why you can't compare Covid-19 vaccines

‘In the US, the first two available Covid-19 vaccines were the ones from Pfizer/BioNTech and Moderna. Both vaccines have very high "efficacy rates," of around 95%. But the third vaccine introduced in the US, from Johnson & Johnson, has a considerably lower efficacy rate: just 66%.

‘Look at those numbers next to each other, and it's natural to conclude that one of them is considerably worse. Why settle for 66% when you can have 95%? But that isn't the right way to understand a vaccine's efficacy rate, or even to understand what a vaccine does. And public health experts say that if you really want to know which vaccine is the best one, efficacy isn't actually the most important number at all.’

View here (Vox, Youtube, Mar 20, 2021)

Moderna begins study of Covid-19 vaccine in kids

‘Moderna Inc has begun dosing patients in a mid-to-late stage study of its COVID-19 vaccine, mRNA-1273, in children aged six months to less than 12 years, the company said on Tuesday (Mar 16). The study will assess the safety and effectiveness of two doses of mRNA-1273 given 28 days apart and intends to enrol about 6,750 children in the United States and Canada.’

Read here (Channel News Asia, Mar 16, 2021)

Coronavirus and the money behind vaccines

The FT explains how the vaccine market works – including the cost of a vaccine and the vaccine development process – and the impact of the Covid-19 pandemic. This short documentary features global experts including Bill Gates, the CEOs of Moderna and Gavi, and the lead scientist behind the Oxford/AstraZeneca vaccine. 

View here (Financial Times, Youtube, Mar 10, 2021)

From Pfizer to Moderna: Who's making billions from Covid-19 vaccines?

‘Among the biggest winners will be Moderna and Pfizer – two very different US pharma firms which are both charging more than $30 per person for the protection of their two-dose vaccines. While Moderna was founded just 11 years ago, has never made a profit and employed just 830 staff pre-pandemic, Pfizer traces its roots back to 1849, made a net profit of $9.6bn last year and employs nearly 80,000 staff.

‘But other drugmakers, such as the British-Swedish AstraZeneca and the US pharma Johnson & Johnson, have pledged to provide their vaccines on a not-for-profit basis until the pandemic comes to an end.’

Also carried in this story are: Sinovac, Sputnik V, Novavax, CureVac 

Read here (The Guardian, Mar 6, 2021)

Efficacy and safety of the mRNA-1273 SARS-CoV-2 vaccine

‘It is important to note that all the severe Covid-19 cases were in the placebo group, which suggests that mRNA-1273 is likely to have an effect on preventing severe illness, which is the major cause of health care utilization, complications, and death. The finding of fewer occurrences of symptomatic SARS-CoV-2 infection after a single dose of mRNA-1273 is encouraging; however, the trial was not designed to evaluate the efficacy of a single dose, and additional evaluation is warranted.

‘Overall, the safety of the mRNA-1273 vaccine regimen and platform is reassuring; no unexpected patterns of concern were identified. The reactogenicity associated with immunization with mRNA-1273 in this trial is similar to that in the phase 1 data reported previously. Overall, the local reactions to vaccination were mild; however, moderate-to-severe systemic side effects, such as fatigue, myalgia, arthralgia, and headache, were noted in about 50% of participants in the mRNA-1273 group after the second dose. These side effects were transient, starting about 15 hours after vaccination and resolving in most participants by day 2, without sequelae.’

Read here (New England Journal of Medicine, Feb 4, 2020)

A new vaccine to battle Covid-19 -- NEJM editorial

‘That the mRNA-1273 Covid-19 and the BNT162b2 Covid-19 vaccines protect with near-identical 94 to 95% vaccine efficacies — and that both vaccines were developed and tested in less than a year — are extraordinary scientific and medical triumphs. This happened because the scientific community was prepared from years of technology development for other vaccines, such as those against HIV, influenza, respiratory syncytial virus, and Zika, and because clinical trials consortia were established that rapidly carried out Covid-19 efficacy trials. If mRNA-LNP vaccines significantly contribute to control of the pandemic, mRNA technology has the potential to radically change vaccine design for future viral outbreaks.

‘Although the Covid-19 pandemic is currently raging, the prospects for control of this and future pandemics are bright. The recent FDA issuance of EUAs for these extraordinarily protective vaccines provide us with much-needed hope at a time when so many are suffering. The next challenge is to get these and the next Covid-19 vaccines to the people most at risk as quickly as possible.’

Read here (New England Journal of Medicine, Feb 4, 2020)

Can you still transmit Covid-19 after vaccination?

‘In fact, most vaccines don't fully protect against infection, even if they can block symptoms from appearing. As a result, vaccinated people can unknowingly carry and spread pathogens. Occasionally, they can even start epidemics. 

"Effective" or "sterilising" immunity: There are two main types of immunity you can achieve with vaccines. One is so-called "effective" immunity, which can prevent a pathogen from causing serious disease, but can't stop it from entering the body or making more copies of itself. The other is "sterilising immunity", which can thwart infections entirely, and even prevent asymptomatic cases. The latter is the aspiration of all vaccine research, but surprisingly rarely achieved.

What type of immunity do the Covid-19 vaccines provide? "In a nutshell we don't know, because they’re too new," says Neal. So far, the available Covid-19 vaccines have not been judged primarily on their ability to prevent transmission – though this is now being evaluated as a secondary endpoint for many of them. Instead, their efficacy was assessed by whether they could prevent symptoms from developing. "This means that we set our targets kind of pragmatically," says Danny Altmann, professor of immunology at Imperial College London.’

Read here (BBC, Feb 4, 2021)

How Singapore picked its Covid-19 vaccines

‘Last June, Singapore sealed its first deal to buy Covid-19 vaccines - before any of the more than 200 vaccine candidates had even started their phase three clinical trials. It decided not to wait for the trials, and even paid a premium on the price, in order to secure some early stock of vaccines for people here at high risk, such as healthcare workers and the elderly. That was for the Moderna mRNA vaccine, which has yet to be approved for use here.

‘Singapore signed two more purchase agreements in August - with Sinovac which produces a traditional vaccine, and Pfizer-BioNTech which also uses mRNA. These purchases should provide sufficient vaccines for the entire adult population. But Singapore is buying more. Dr Benjamin Seet, who chaired the panel that picked the vaccines for Singapore, said several late-stage discussions are still ongoing with a handful of other companies - as part of a contingency plan should there be disruptions in the supply of purchased vaccines, delays in the delivery, or even the need for further booster shots.’

Read here (Straits Times, Feb 1, 2021) 

Chinese health experts call to suspend Pfizer's mRNA vaccine for elderly after Norwegian deaths

‘Chinese health experts called on Norway and other countries to suspend the use of mRNA-based COVID-19 vaccines produced by companies such as Pfizer, especially among elderly people, due to the vaccines' safety uncertainties following the deaths of 23 elderly Norwegian people who received the vaccine. 

‘The new mRNA vaccine was developed in haste and had never been used on a large scale for the prevention of infectious disease, and its safety had not been confirmed for large-scale use in humans, a Chinese immunologist said. The death incidents in Norway also proved that the mRNA COVID-19 vaccines' efficacy was not as good as expected, experts said. 

‘As of Thursday, Norway has reported 23 deaths in connection with vaccination."So far, 13 of these have been assessed. Common side effects may have contributed to a severe course in frail elderly people," the Norwegian Medicines Agency said on its website. All the deaths have occurred in frail, elderly patients in nursing homes. All are over 80 years old and some of them over 90, Norwegian media NRK reported.’

Read here (Global Times, Jan 15, 2021)

Moderna CEO: World will have to live with COVID-19 ‘forever’

‘As new, more infectious variants of COVID-19 continue to pop up in the U.S. and other parts of the world, Stephane Bancel, CEO of Moderna, which is the maker of one of two coronavirus vaccines approved for use by the Food and Drug Administration, believes the virus could be around “forever.”

‘Speaking during a panel discussion at the annual JPMorgan Healthcare Conference, Bancel said he agrees with emerging data suggesting that “SARS-CoV-2 is not going away. We are going to live with this virus, we think, forever,” he said, according to a CNBC report.’

Read here (Christian Post, Jan 15, 2021)

Peter Doshi: Pfizer and Moderna’s “95% effective” vaccines—we need more details and the raw data

Peter Doshi: Pfizer and Moderna’s “95% effective” vaccines—we need more details and the raw data 

‘Five weeks ago, when I raised questions about the results of Pfizer’s and Moderna’s covid-19 vaccine trials, all that was in the public domain were the study protocols and a few press releases. Today, two journal publications and around 400 pages of summary data are available in the form of multiple reports presented by and to the FDA prior to the agency’s emergency authorization of each company’s mRNA vaccine. While some of the additional details are reassuring, some are not. Here I outline new concerns about the trustworthiness and meaningfulness of the reported efficacy results...’

Read here (BMJ, Jan 4, 2021) 

Feds may cut Moderna vaccine doses in half so more people get shots, Warp Speed adviser says

‘The federal government is in talks with Moderna about giving half the recommended dose of the company's Covid-19 shot to speed up immunization efforts, the head of the Trump administration's vaccine rollout said on Sunday.

‘Operation Warp Speed chief adviser Moncef Slaoui said there is evidence that two half doses in people between the ages of 18 and 55 gives “identical immune response” to the recommended one hundred micorogram dose, but said the final decision will rest with the FDA.’

Read here (Politico, Jan 3, 2021)

Suspicions grow that nanoparticles in Pfizer’s COVID-19 vaccine trigger rare allergic reactions

‘Severe allergy-like reactions in at least eight people who received the COVID-19 vaccine produced by Pfizer and BioNTech over the past 2 weeks may be due to a compound in the packaging of the messenger RNA (mRNA) that forms the vaccine’s main ingredient, scientists say. A similar mRNA vaccine developed by Moderna, which was authorized for emergency use in the United States on Friday, also contains the compound, polyethylene glycol (PEG).

‘PEG has never been used before in an approved vaccine, but it is found in many drugs that have occasionally triggered anaphylaxis—a potentially life-threatening reaction that can cause rashes, a plummeting blood pressure, shortness of breath, and a fast heartbeat. Some allergists and immunologists believe a small number of people previously exposed to PEG may have high levels of antibodies against PEG, putting them at risk of an anaphylactic reaction to the vaccine.’

Read here (Science magazine, Dec 21, 2020)

European Commission embarrassed by Covid-19 vaccine price leak

‘The tweeted information gave the following price per dose for each vaccine maker, in either euros or US dollars according to the respective contract:

1. AstraZeneca: €1.78
2. Johnson & Johnson: US$8.50
3. Sanofi/GlaxoSmithKline: €7.56
4. Pfizer/BioNTech: €12.00
5. Curevac: €10.00
6. Moderna: US$18.00’

Read here (Malay Mail, Dec 18, 2020) 

WHO to make decisions on Pfizer, Moderna, AstraZeneca COVID-19 vaccines in weeks

‘The World Health Organization expects to make decisions on whether to give emergency use approval to COVID-19 vaccines from Pfizer, Moderna and AstraZeneca in the coming weeks, its chief scientist said on Friday (Dec 11).

‘Soumya Swaminathan said the global health body could decide on Pfizer's vaccine candidate in the next "couple of weeks", and later said it could also review Moderna's and AstraZeneca's candidates in a few weeks.’

Read here (Channel News Asia, Dec 12, 2020)

The science behind an RNA vaccine

‘In just 10 months, a vaccine developed by Pfizer and BioNTech has been approved by Britain for emergency use to prevent Covid-19. Another by Moderna is being evaluated for emergency use authorisation by several regulators, including the United States Food and Drug Administration...

‘This 10-month timeline for vaccines to get from concept to licensing is ground-breaking; most take more than 10 years to reach this stage. There are several other RNA vaccines in the pipeline, including the one our team at Duke-NUS Medical School is working on in partnership with Arcturus Therapeutics. Here is the science behind such vaccines...’

Read here (Straits Times, Dec 7, 2020)

What you need to know about the Pfizer, Moderna and AstraZeneca vaccines

‘All three drugmakers have moved at record speed, and the first shots of the Pfizer and Moderna vaccines could be given in the coming weeks. This article answers a list of questions that ordinary people need to know before they commit to the vaccinations.’

Read here (Washington Post, Nov 30, 2020)

Moderna's chief medical officer says that vaccine trial results only show that they prevent people from getting sick — not necessarily that recipients won't still be able to transmit the virus

‘Moderna Chief Medical Officer Tal Zaks told Axios that the public should not "over-interpret" the vaccine trial results to assume life could go back to normal after adults are vaccinated. "They do not show that they prevent you from potentially carrying this virus transiently and infecting others," Zaks told Axios.  While he believes, based on the science, that it's likely that vaccine does prevent transmission, but said there's still no solid proof of that yet. "I think it's important that we don't change behavior solely on the basis of vaccination," he said.’

Read here (Business Insider, Nov 24, 2020)

Doctors say CDC should warn people the side effects from Covid vaccine shots won’t be ‘a walk in the park’

‘The CDC must be transparent about the side effects people may experience after getting their first shot of a coronavirus vaccine, doctors urged during a meeting Monday with CDC advisors. Dr. Sandra Fryhofer said that both Pfizer’s and Moderna’s Covid-19 vaccines require two doses and she worries whether her patients will come back for a second dose because of potentially unpleasant side effects after the first shot. Both companies acknowledged that their vaccines could induce side effects that are similar to symptoms associated with mild Covid-19, such as muscle pain, chills and headache.’

Read here (CNBC, Nov 23, 2020)

The end of the pandemic is now in sight

‘Both vaccines, from Moderna and from Pfizer’s collaboration with the smaller German company BioNTech, package slightly modified spike-protein mRNA inside a tiny protective bubble of fat. Human cells take up this bubble and simply follow the directions to make spike protein. The cells then display these spike proteins, presenting them as strange baubles to the immune system. Recognizing these viral proteins as foreign, the immune system begins building an arsenal to prepare for the moment a virus bearing this spike protein appears... This overall process mimics the steps of infection better than some traditional vaccines, which suggests that mRNA vaccines may provoke a better immune response for certain diseases...

‘All of this is how mRNA vaccines should work in theory. But no one on Earth, until last week, knew whether mRNA vaccines actually do work in humans for COVID-19. Although scientists had prototyped other mRNA vaccines before the pandemic, the technology was still new. None had been put through the paces of a large clinical trial. And the human immune system is notoriously complicated and unpredictable. Immunology is, as my colleague Ed Yong has written, where intuition goes to die. Vaccines can even make diseases more severe, rather than less. The data from these large clinical trials from Pfizer/BioNTech and Moderna are the first, real-world proof that mRNA vaccines protect against disease as expected. The hope, in the many years when mRNA vaccine research flew under the radar, was that the technology would deliver results quickly in a pandemic. And now it has.’

Read here (The Atlantic, Nov 19, 2020)