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Saturday, January 2, 2021

Fauci on Vaccines, Virus Mutations, and 2021

 

  • There is some degree of immunity after the first dose of the COVID-19 vaccines, but it's not optimal and we don't know how long it will last. We do know definitively that immunity increases dramatically after the second dose and lasts considerably longer.

  • A "bridging study" in children will probably begin in mid-January to make sure that the COVID-19 vaccines' efficacy and safety data are comparable to those of the successful adult vaccine trials. It's not necessary to vaccinate children before we reopen schools.

  • April could be "open season" for the general public to start receiving COVID-19 vaccines, as long as the current rollout to priority groups goes smoothly. We could have "umbrella protection" across the country — establishing herd immunity — by the end of summer 2021.

  • People who are hesitant to get a COVID-19 vaccine should be reassured that the approval process has been independent and transparent, made by people who have no allegiance to the federal government or to pharmaceutical companies.

  • Like all RNA viruses, this coronavirus has been mutating, and a new variant that has shown up in the United Kingdom may be more contagious. However, there is no evidence that it is more virulent or that current vaccines will not be effective against it.

John Whyte, MD, MPH: Welcome, everyone. You're watching Coronavirus in Context. I'm Dr John White, chief medical officer at WebMD. Today I have a very special guest, Dr Anthony Fauci, the world's leading authority on infectious diseases. Dr Fauci, thanks for joining us.

Anthony Fauci, MD: Thank you. It's good to be with you.

Whyte: Dr Fauci, I heard that you got the vaccine today, so I wanted to ask you about your experience. How are you feeling?

Fauci: I'm feeling perfectly fine, normal. Nothing so far. I have no pain in my arm. I had nothing to even indicate that I had been vaccinated. That was about 3-4 hours ago. I'm doing great.

Whyte: People ask, "Does it feel cold?" They know the vaccines are kept at these super-frozen temperatures. Was there any tingling?

Fauci: No, you really don't feel it at all. I got it with a group of healthcare providers (and I'm also a healthcare provider), and all of us agreed that it was even less of a feeling than with the flu shot. Flu shots sometimes hurt a little. Didn't hurt at all. It was perfectly fine.

Whyte: I want to ask you about the vaccines because you've talked about how impressed you have been with the safety and efficacy data — both Pfizer and Moderna vaccines are 94%-95% effective. If the data are so compelling, why have the vaccines been authorized under emergency use authority (EUA) as opposed to full approval?

Fauci: That's a very good question. The reason is that you want to get it out as quickly as possible — do the full dotting of the i's and crossing of the t's of a biologics license application, the BLA. That would take several more months to do. When you do an EUA, particularly an EUA that's granted on the strength of these data, which is really quite impressive — both of these vaccines not only were safe, but they were 94%-95% efficacious in preventing any clinically recognizable disease, and even better in preventing severe disease.

So, we felt that we wanted to get it out quickly while in the process of putting in for the full license approval. We didn't want to have months go by without people having the advantage of the vaccine. Given the extraordinary situation in our country — as you well know, we're in a very difficult situation. We're having 200,000 and more cases per day and anywhere between 2000 and 3000 deaths per day. Hospitalizations have reached a record of 118,000. Places like California are being stressed to the point that they may run out of beds. So you don't want to be delaying vaccine merely because bureaucratically you have to go through a bunch of hoops to get the official approval. The data are quite strong to grant an EUA.

Whyte: Given the number of infections and deaths and the scarcity of the vaccine right now, some people have been saying, "Let's not focus on two doses. There's some significant efficacy after the first dose." Why not just start giving more people the first dose (one is better than none)? What are your thoughts about that approach?

Fauci: That has been discussed a fair amount, and what people don't appreciate, even though there is some degree of efficacy after a single dose, is that it is really not optimal at all and we don't know how long it lasts. We do know definitively that even though you do get some degree of immunity after the prime single dose, after the second dose it's dramatically higher and it lasts considerably longer.

Whyte: What about data and children, particularly those less than 12 years old? We know the journey of the disease in children; should we be worrying about vaccinating them vs teachers, essential workers, and other adults?

Fauci: Well, you want to do both. When we make and test the vaccine, we don't want to test it on children because children are vulnerable. They do not have the capability of giving informed consent, which is important. It's their life. Though they're very young, it's still their life. So you've got to take extra special care in safety.

The standard traditional thing we do is a vaccine study that's a phase 3 large study in adults. When you get good safety and data on efficacy, then you can feel justified in taking the risk of trying it in a child. You can do a phase 1, phase 2 in a child after you complete the vaccine trial in the adult, and then quickly get the children to get vaccinated by what's called a "bridging study."

A bridging study means you don't have to spend the entire time with tens of thousands of children the way we did with the adults. You can do a couple of thousand — 2000-4000 kids — show that it's safe, and show that it induces the kind of response that's comparable to the response that protected the adult. Then you can make the assumption that it will protect children, and then you license it because you've proven safety and you have a very good indication that it likely will protect children. We're going to start that probably in the middle to the end of January.

Whyte: Do we need to vaccinate kids before we can reopen schools?

Fauci: No, I don't think that that's necessary. I think that the default position should be, as best as possible, to keep the children in school or get them back to school if they're not in school. We know now that, all other things being equal, children in school get infected less than the adults in the community. If you have the capability of dealing with kids when they get infected, you have reasonably good surveillance — like maybe vaccinate the teachers to protect them in the school and prevent them from infecting the children.

Whyte: Those are on the next prioritization list as well. I want to ask you about vaccine confidence. You might have seen the data from a USA Today survey that just came out, which talks about Democrats being nearly twice as willing as Republicans to receive the vaccine. Even more concerning is that 36% of Republicans say they'll never take the vaccine. How do we get to 70%-80% herd immunity if we have these issues with confidence in the vaccine? What are the one or two things that we need to be doing now to inspire confidence?

Fauci: Well, I think we need outreach to the communities of all people — Republican and Democrat, minorities, and people in the general population. The way we have approached it is to not confront people who are hesitant or who have skepticism, but try to reason with them and say, "What are the reasons why you have skepticism?" And there are a couple of well-defined reasons.

If the reason is "Boy, this went really quickly. Was it careless and quick?", then you show that the fact that we went from a brand-new virus in January to a vaccine that we're putting into people in December is not compromising safety, nor is it compromising scientific integrity. It is a reflection of the extraordinary scientific advances that have been made in vaccine platform technology, which have allowed us to do things in months that normally would have taken years. There's no compromise in safety.

The next question people ask, understandably, is " You're saying that it's safe and you're saying that it's effective. Is that true or is this the government putting pressure on you? Is it the pharmaceutical companies wanting to make a lot of money?"

Whyte: So tell us: What's the answer?

Fauci: The answer is — and this is important —the decision of whether something is safe and effective. The data get examined by a totally independent data and safety monitoring board made up of vaccinologists, virologists, immunologists, statisticians, and others. They have no allegiance, don't answer to the federal government, don't answer to the pharmaceutical company. They're an independent group. When they decide that the vaccine data look really good and it's safe and effective, they then give the data to the company that presents it to the FDA. Then the career scientists at the FDA — not political appointees, but the career scientists — work with their own independent advisory committee; they have an established committee called the Vaccines and Related Biological Products Advisory Committee, or VRBPAC. They then say, "Okay, it's cleared. Let's give it."

So in reality, the entire process is independent and transparent, and that's what people need to know. And when they do, I believe they will be much more amenable to getting vaccinated.

Whyte: Everyone's talking about the variant and the concern about whether the vaccine will be effective. What are the countermeasures that we need to be taking now? You've been saying we don't want to overreact, and others are saying, "Now is the time that we need to be overly cautious in a way." What's your response to assuage people's concerns about what they might be hearing on the news or reading online about the impact of these potential variants?

Fauci: I think they need to understand something broadly at 40,000 feet: that this is an RNA virus, and RNA viruses mutate all the time. Their occupation is mutating. The more they replicate, the more they mutate. Most of the mutations do not have any functional significance or functional relevance. The one that's being looked at now, the one that's dominant in the United Kingdom, is one that appears — we don't know for sure — but it looks like it has a better capability of transmitting, of going from person to person. There's no evidence that it has any effect on its virulence or, namely, that it makes people more sick. It doesn't.

The other important issue is whether it's evading the protection of a vaccine, and it doesn't appear that that's the case at all. So, what we need to do is watch it very carefully, and we need to do surveillance in this country. Then there is discussion about: If it isn't already here — which it might well be and we don't know it yet — what do you do? I know the European Union is banning travel from the UK. I think that may be an overreaction now. I would not be against at least making sure that people who fly here, or come to the United States from the UK, be required to be tested before they get on the plane so that you know they're negative when they get here. That, I think, is something that might be considered. I'm not saying we should do it, but we should consider it.

Whyte: Those are all good points. You know, I always ask my colleagues, "What should we ask Dr Fauci?" So I want to give them an opportunity. The question was: "Many people have postponed their weddings from 2020 to March or April of 2021. Do they need to postpone it again?"

Fauci: You know, they should have postponed it until June or July.

Whyte: I don't think they'll be happy to hear that.

Fauci: I'm sorry, John. We don't know. I think it's going to work out that way if we do it efficiently. It depends on how efficient we are. If we get the priority people vaccinated, the ones that the ACIP (Advisory Committee on Immunization Practices) is recommending, by March or beginning of April, we could then start in April doing what I call "open season" on vaccinations — namely, anybody in the general population who wants to get vaccinated will get vaccinated. If that's the case (when we go through April, May, June, July), by the time we get into the middle or end of the summer, I believe we can have 70%-85% of the population vaccinated if we do it correctly. When that occurs, there will be an umbrella of protection over the entire country. The level of virus will be so low that you have essentially been able to establish herd immunity. So I'm looking forward to it as we finish the second quarter and go into the third quarter of 2021.

Whyte: And finally, I want to ask you about the "Fauci effect" — the impact that you're having on young students who are saying, "I want to go into medicine; I want to go into science." When you heard about the Fauci effect, how did you feel?

Fauci: Well, I felt good that young people want to go into a profession that I love and that I have been in for so many years. It goes beyond me. They're calling it the Fauci effect, and I'm very flattered that that's the case. But I think it also relates to the courage of the healthcare providers in the emergency rooms and in the intensive care units. People are seeing a face of medicine that they may not have seen before, of people who are really stepping up to the plate and doing their job. I'm doing it by trying to speak truth to the country and trying to be clear in the explanation of what is going on in a way that they understand. The healthcare providers are risking themselves, their health, and their lives every day to take care of people. So I think that the face of medicine is a much more attractive face now than it may have been in the past.

Whyte: My colleagues have also wanted me to ask you, "In terms of your professional career, you've dealt with HIV, Ebola, other pandemics around the world. Why has COVID-19 been so difficult? Is it the politics around this issue? Is it the impact of social media that didn't exist before? Why is it so hard now?"

Fauci: Whenever you have a public health outbreak — a really transforming outbreak, the likes of which we haven't seen in 102 years — everyone has got to pull together to get a maximum impact on addressing it. Unfortunately, we are living in a very divisive society. I think anybody that looks at what's going on in the United States has to realize that there is a lot of divisiveness. That makes it much more difficult because simple public health measures take on a political connotation.

You said it yourself when you gave the numbers. Why should there be any difference between a Republican and a Democrat as to whether they want to take a vaccine or not? There's no reason why there should be because it's a public health issue. I think it's just a reflection of the kind of divisiveness we see. So, you're right, that it has made it difficult, because it has led to mixed messaging. And when you get mixed messaging, people get confused as to what the best thing to do is. You've really got to be uniform and consistent when you're fighting something as serious as a pandemic.

https://www.medscape.com/viewarticle/943131

Vaccine's Slow Rollout Could Portend More Problems

 Three weeks into the most ambitious vaccination campaign in modern U.S. history, far fewer people are being protected against Covid-19 as the process moves slower than officials had projected and has been beset by confusion and disorganization in many states.

As a result, the federal government came nowhere close to vaccinating 20 million people by the end of 2020, as it had promised.

Of the more than 12 million doses of vaccines from Moderna Inc. and Pfizer Inc. with BioNTech SE that have been shipped, only 2.8 million have been administered, according to federal figures.

The shortfall is due in part to a lag in reporting data using new tools, government officials and health experts said. But as the federal government has left it to states to determine what to do with the vaccines it ships to them, and with some states pushing decision-making to local health departments and hospitals, the process has gone far from smoothly.

People in Florida are waiting in hourslong lines to get shots on a first-come, first-served basis. Some West Virginians got a Covid-19 treatment instead of vaccines. A medical practice in Texas had only two workers sign up to take the shots. While some states received fewer doses than they expected and some hospitals got their first ones this week, other health care providers have more doses than they know what to do with and are scrambling to find enough syringes to use them.

"Hospitals aren't vaccinating everyone at the flip of a light switch," said Claire Hannan, executive director of the Association of Immunization Managers, which represents state immunization officials. "There may have been an expectation from Operation Warp Speed or others that we'd give everyone the vaccine overnight....It was a logistics equation for them. If you've been in vaccines for a long time, you know that's the easy part. Getting it into actual arms is the hard part."

So far, vaccines have mostly gone to health care workers and residents of long-term care facilities, in line with guidelines from the Centers for Disease Control and Prevention. Essential workers like bus drivers or grocery clerks, plus older adults, are expected to be vaccinated next in 2021 as supplies increase and as more vaccination sites come online. The slow rate of vaccinations so far has raised questions about whether those groups will start getting shots this winter and the rest of Americans in the spring, as initially projected.

Moncef Slaoui, chief adviser for Operation Warp Speed, the U.S. government's coronavirus response program, and other federal officials said they hope the pace will increase. "We agree that that number is lower than what we hoped for," he said at a news briefing Wednesday. "We know that it should be better, and we're working hard to make it better."

Public health officials and states say uptake is lagging for several reasons, beginning with holiday seasons that have kept staff of hospitals and nursing homes away from work. They also note they are facing high percentages of people, including some health care workers, who are skeptical of taking the shots.

Hospitals and other sites are staggering appointments to avoid pulling too many workers from caring for patients amid a nationwide surge in Covid-19 cases, officials say. Administration of the vaccines also takes more time than a typical flu shot, particularly since they are being done socially distant, and may be preceded by a Covid-19 test.

In addition, people who receive vaccines are being monitored for at least 15 minutes in case of allergic reactions. At least 11 allergic reactions to Covid vaccines have been reported, according to the CDC. No serious safety concerns have been found, in line with findings from the clinical trials.

The federal government is sending vaccines to states based on their populations, and it has provided guidelines, but no rules, about how they should be distributed. State and local jurisdictions have been asking the federal government for more funding to support vaccine distribution than the $340 million disbursed so far. The economic stimulus package recently signed into law by President Trump contains an additional $8 billion.

Different state policies have led to confusion and shipment delays for hospitals, said Michael Wascovich, vice president of field pharmacy services for Premier Inc., a group purchasing organization whose members include 4,100 hospitals, 80% of which received doses.

"Every state is doing what they want to do," he said. "You could be in Philadelphia and it's completely different across the river if you're in Trenton or Camden."

Community Health Systems Inc., which operates 86 hospitals, is seeking state permission to redistribute doses across its Florida hospitals, while three hospitals in Indiana got no vaccine and workers must get shots elsewhere, complicating efforts to track company immunization rates. "It's not within our control," said Lynn Simon, the hospital system's chief medical officer. "It is a little anxiety producing."

In Grand Rapids, Mich., Spectrum Health had lowered supply estimates as the state repeatedly revised projections. Hospital officials were stunned to learn two days before Christmas they would get 60% more than expected of Pfizer's shot and more than double Moderna's, said Chad Tuttle, senior vice president of operations across Spectrum's 14 hospitals.

Many states are following CDC guidelines to start with front-line medical workers and people in long-term care facilities, but not all. Florida Gov. Ron DeSantis on Dec. 23 extended eligibility to people aged 65 and older.

Because each county and hospital in the state implemented its own approach, many people didn't know whether to call, log on or show up in person to secure a spot.

Officials in Lee County, home to Fort Myers, learned last Saturday that the county would be one of eight in the state receiving doses the following day to inoculate people 65 and older, said Kevin Ruane, chairman of the county commission. With the local health department thinly staffed, they rushed to enlist paramedics and others. They weren't able to set up a reservation system, leading to hundreds of people lining up before dawn.

"It's a logistical nightmare," said Fort Myers Mayor Kevin Anderson.

Frustrated by the slow pace of inoculations, Arizona Gov. Doug Ducey issued an executive order Wednesday directing the state health department to create a vaccine-allocation system and allowing the agency to take possession of doses for reassignment.

Forty-two people in West Virginia were mistakenly given Regeneron Pharmaceuticals Inc.'s antibody treatment designed to fight Covid-19 in those already infected instead of Moderna's vaccine. None are at risk of being harmed, according to the West Virginia National Guard.

In Hidalgo County, Texas, one medical practice received 1,000 doses for health-care workers, but only two people responded, said Ivan Melendez, the public health authority for the county near the Mexican border.

"I think there was an overestimation of the numbers," Dr. Melendez said. "All of a sudden, there's a glut of vaccines."

More than 167,000 doses have been administered at long-term medical care centers. Facilities are getting shots at varying rates via drugstore chains CVS Health Corp. and Walgreens Boots Alliance Inc. because states met the requirements to begin the distribution program at different times.

CVS has begun administering doses at nursing homes and facilities in 48 states and Washington, D.C., with most eligible residents agreeing to be vaccinated, said Chris Cox, a CVS executive who is overseeing the vaccination rollout for the pharmacy chain.

In some cases, residents haven't been vaccinated because of active outbreaks at facilities, while other facilities have taken longer than others to schedule their vaccination clinics, a challenge exacerbated by the holiday season, Mr. Cox said.

West Virginia is the only state to report having delivered the first of two vaccine doses to all of its approximately 200 long-term care facilities. More than 80% of eligible residents have been vaccinated because the state relied on some 50 local pharmacies, said Martin Wright of the West Virginia Health Care Association, a nursing home trade group.

Many hospitals saw an opportunity to inoculate more people after discovering Pfizer's vials yielded six or seven doses instead of five due to so-called overfill, which typically happens with vaccines. The development sent hospitals scouring for more syringes and needles to utilize the extra doses, said Mr. Wascovich of Premier.

"They all value it like it's worth its weight in gold," he said.

Now, some public health officials are concerned the country may not be ready for the next phase of vaccination, expected to include essential workers such as grocery store clerks or first-responders.

The U.S. health system and its stretched local health departments weren't prepared for the volume to vaccinate an entire country in a few months, according to Ms. Hannan, the director of the immunization association.

"The real challenge is around what happens when we get a larger supply and what happens when we have to vaccinate people that don't work in a hospital," she said, noting that fewer physicians' offices and health clinics have signed up as vaccination sites than she expected.

Vaccination for the next priority groups, 49 million elderly people and front-line essential workers, such as teachers and grocery store workers, is expected to begin in the coming weeks, according to health experts. Delays so far could push back the start dates of those programs, however.

In addition, states will likely make different determinations about who counts as essential and which groups go first, potentially frustrating the public, health experts warn. Prison guards in one state might get inoculated months before those in a neighboring one.

"Those could be points of confusion in the week ahead as people try to figure out, 'Where am I in line?' " said Dr. Kelly Moore, associate director of immunization education at the Immunization Action Coalition.

https://www.marketscreener.com/quote/stock/BIONTECH-SE-66771992/news/Covid-19-Vaccine-s-Slow-Rollout-Could-Portend-32109469/

India drug regulator's expert body recommends two COVID vaccines for emergency use

 Experts at India’s drug regulator have recommended emergency-use approval for the AstraZeneca/Oxford vaccine and another developed locally by Bharat Biotech and a state-run research body, the government said on Saturday.

https://www.reuters.com/article/health-coronavirus-india-vaccine-two/india-drug-regulators-expert-body-recommends-two-covid-vaccines-for-emergency-use-idUSKBN2970DS

Britain will allow mixing of COVID-19 vaccines on rare occasions

 Britain will allow people to be given shots of different COVID-19 vaccines on rare occasions, despite a lack of evidence about the extent of immunity offered by mixing doses.

In a departure from other strategies globally, the government said people could be given a mix-and-match of two COVID-19 shots, for example if the same vaccine dose was out of stock, according to guidelines published on New Year’s Eve. “(If) the same vaccine is not available, or if the first product received is unknown, it is reasonable to offer one dose of the locally available product to complete the schedule,” according to the guidelines.

Mary Ramsay, head of immunisations at Public Health England, said this would only happen on extremely rare occasions, and that the government was not recommending the mixing of vaccines, which require at least two doses given several weeks apart.

“Every effort should be made to give them the same vaccine, but where this is not possible it is better to give a second dose of another vaccine than not at all,” she said.

COVID-19 has killed more 74,000 people in Britain - the second-highest death toll in Europe, and health officials are racing to deliver doses to help end the pandemic as fears grow that the health service could be overwhelmed.

Earlier this week, the government reactivated emergency hospitals built at the start of the outbreak as wards fill up with COVID-19 patients.Britain has been at the forefront of approving the new coronavirus vaccines, becoming the first country to give emergency authorisation to the Pfizer/BioNTech and the AstraZeneca/University of Oxford vaccines last month.

Both vaccines are meant to be administered as two shots, given several weeks apart, but they were not designed to be mixed together.

The government’s new guidelines said there “is no evidence on the interchangeability of the COVID-19 vaccines although studies are underway”.

However, the advice said that while every effort should be made to complete the dosing regimen with the same vaccine, if the patient is at “immediate high risk” or is considered “unlikely to attend again” they can be given different vaccines.

Britain sparked controversy earlier this week by announcing plans to delay giving the coronavirus vaccine booster shot in an attempt to ensure more people could be given the more limited protection conferred by a single dose.

The top U.S. infectious diseases expert, Anthony Fauci, said on Friday he did not agree with the British approach of delaying the second dose up to 12 weeks.

“I would not be in favour of that,” he told CNN. “We’re going to keep doing what we’re doing.”

https://www.reuters.com/article/health-coronavirus-britain-vaccine/britain-will-allow-mixing-of-covid-19-vaccines-on-rare-occasions-idUSKBN2970CK

AstraZeneca to supply 2M doses of COVID-19 vaccine every week in UK

 

  • 2M doses of COVID-19 vaccine developed by AstraZeneca (NASDAQ:AZN) and the Oxford University will reach the U.K. every week by mid-January, The Times reportsciting an unnamed member of the Oxford-AstraZeneca team.
  • “The plan is then to build it up fairly rapidly - by the third week of January we should get to two million a week,” the report said.
  • The U.K. government has ordered 100M doses of the Oxford-AstraZeneca COVID-19 vaccine, more than 40M and 5M ordered from Pfizer (NYSE:PFE)/ BioNTech (NASDAQ:BNTX), and Moderna (NASDAQ:MRNA), respectively.
  • Meanwhile, amid the raging infection in the country, the U.K government has updated the COVID-19 vaccination guidelines allowing the second shot of both the BioNTech/Pfizer and Oxford/AstraZeneca vaccines to be delivered as much as three months after the first.
  • However, Pfizer, whose vaccine won the approval in early December, has questioned the move, reiterating the importance of the 21-day gap recommended for the booster dose.
  • Early this week, the Oxford-AstraZeneca COVID-19 vaccine that uses a replication-deficient chimpanzee viral vector was granted emergency approval in the U.K. with a delay of 12 weeks recommended between the two-dose regimen.
  • https://seekingalpha.com/news/3648177-astrazeneca-to-supply-2m-doses-of-covidminus-19-vaccine-every-week-in-u-k-times

Pfizer/BioNTech to speed up vaccination of placebo arm in COVID trial

 

  • In the ongoing late-stage trial for the COVID-19 vaccine developed by Pfizer (NYSE:PFE) and BioNTech (NASDAQ:BNTX), the participants in the placebo arm will now have the option to receive the investigational vaccine by March 01, 2021, according to an announcement on a website about the study
  • All subjects in the placebo arm will have two doses of the vaccine reserved. In the coming weeks, the volunteers will be offered the option to go unblind (To know if they were in the vaccine or placebo group) on a priority basis and receive the vaccine, the statement added.
  • Despite arguments against such a move by the FDA and its advisors, the Vaccine Transition Option arrives a few months ahead of the initial plan, according to STATNews, as the coronavirus pandemic rages across the U.S. with the total number of cases exceeding 20M
  • Meanwhile, citing the federal data, the Wall Street Journal reports that only 2.8M of 12M doses shipped by Pfizer/BioNTech and Moderna (NASDAQ:MRNA) have been administered, risking the smooth rollout of the next phase targeting the older adults and essential workers.
  • Involving 44,000 participants, the Phase 2/3 study of the COVID-19 vaccine from Pfizer/BioNTech is currently in progress across 150 clinical trial sites in the U.S.
  • https://seekingalpha.com/news/3648181-pfizer-biontech-to-speed-up-vaccination-of-placebo-arm-in-covidminus-19-trial

AstraZeneca receives emergency use nod for coronavirus vaccine in India