The 2023 Nobel Prize: Karikó and Weissman

On 2 October 2023, the Nobel Assembly at Karolinska Institutet in Stockholm awarded the Nobel Prize in Physiology or Medicine to Katalin Karikó and Drew Weissman. This page is the record of that prize: the exact words of the citation, who made the decision and under which rules, what the committee wrote about the science, the lectures and the ceremony, the honours that came first, the question of who else built the mRNA vaccines, and the earlier Nobel prizes this one stands on. Every quotation comes from the Nobel documents on nobelprize.org, from the awarding bodies’ own pages, or from the scientific papers, and each source is listed at the foot of the page.

The two scientists’ personal story, and the full benefit-and-harm record of the vaccines their discovery made possible, are on our main Karikó & Weissman page. Readers who arrived from Dr. Bryan Ardis’s account of “snake venom phosphodiesterase” in the pair’s papers will find what the Nobel documents contain on that point in Section 9, and the papers’ own sentences on our Snake Venom Phosphodiesterase page.

Table of Contents

  1. The Announcement
  2. What the Committee Said They Discovered
  3. The Two Laureates
  4. The Lectures and the Ceremony
  5. The Honours Before the Nobel
  6. A Nobel Rewards a Discovery, Not a Product
  7. Who Else Built the mRNA Vaccines
  8. The Nobel Prizes Behind This One
  9. Questions Readers Ask
  10. Key Research Papers
  11. Connections
  12. Featured Videos

1. The Announcement

The decision was announced in Stockholm on 2 October 2023. The press release opens with one sentence that is the whole of the official citation:

“The Nobel Assembly at Karolinska Institutet has today decided to award the 2023 Nobel Prize in Physiology or Medicine jointly to Katalin Karikó and Drew Weissman for their discoveries concerning nucleoside base modifications that enabled the development of effective mRNA vaccines against COVID-19”

Three phrases carry the meaning. Nucleoside base modifications are small chemical changes to the letters of RNA (Section 2 explains them in plain words). Discoveries concerning those changes are what was rewarded. And the vaccines are named as what the discoveries enabled — the result, not the prize-winning work itself (Section 6).

Who decides

Alfred Nobel’s will, drawn up on 27 November 1895, left one part of the prize fund “to the person who shall have made the most important discovery within the domain of physiology or medicine,” and it named the judge: the prize “for physiological or medical works” is awarded “by Karolinska Institutet in Stockholm.” Under the statutes of the Nobel Foundation, “the duties devolving upon Karolinska Institutet under the will shall be performed by the Nobel Assembly of Karolinska Institutet.” The committee describes the arrangement in two sentences at the foot of its press release: “The Nobel Assembly, consisting of 50 professors at Karolinska Institutet, awards the Nobel Prize in Physiology or Medicine. Its Nobel Committee evaluates the nominations.” A useful picture: the small committee works like an expert panel that reads the nominations and writes the report, and the 50-member Assembly makes the decision.

The rules are strict. A candidate must be “nominated in writing by a person competent to make such a nomination,” and “a personal application for an award shall not be considered”; each year’s prize weighs the nominations received up to 1 February. “No appeals may be made against the decision,” and the nominations, investigations and opinions behind a prize “may not be divulged” — the statutes allow access to that material only after “at least 50 years have elapsed from the date of the relevant prize decision.” For the 2023 prize, that means not before 2073.

The citation says “jointly.” The prize was not split between two different discoveries; it went to two people for one body of work, and the laureates’ fact pages on nobelprize.org list each with a “Prize share: 1/2.”

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2. What the Committee Said They Discovered

The press release tells the science as a short story. Lab-made messenger RNA — produced in a test tube by a method called in vitro transcription, introduced in the 1980s — was hard to turn into medicine: it “was considered unstable and challenging to deliver,” and it “gave rise to inflammatory reactions.” Then: “Karikó and Weissman noticed that dendritic cells recognize in vitro transcribed mRNA as a foreign substance, which leads to their activation and the release of inflammatory signaling molecules. They wondered why the in vitro transcribed mRNA was recognized as foreign while mRNA from mammalian cells did not give rise to the same reaction.”

Here is the idea in plain words. RNA is written with four letters — A, U, G and C. Your cells do not leave their own RNA as plain letters; they decorate many of them with small chemical marks. RNA made in a test tube carries no such marks. The immune system’s sentries, the dendritic cells, treat that difference as an alarm: plain, unmarked RNA looks like a virus. The press release again: “Karikó and Weissman knew that bases in RNA from mammalian cells are frequently chemically modified, while in vitro transcribed mRNA is not.” So they made mRNA with modified letters and tested it. “The results were striking: The inflammatory response was almost abolished when base modifications were included in the mRNA.” One of the modified letters was pseudouridine (Ψ), a natural, slightly rearranged form of the letter U. The committee’s background puts it in context: researchers have found “more than one hundred different post-transcriptional modifications in RNA,” and pseudouridine “was discovered already in 1951” and “is one of the most abundant RNA modifications.”

An everyday comparison: a letter on your own household stationery passes the front door without a second look, while an unsigned note in a stranger’s hand gets taken to security. The modified letters work like the household stationery.

“These seminal results were published in 2005, fifteen years before the COVID-19 pandemic.” — Nobel press release, 2 October 2023

The committee then credits two follow-up papers: “In further studies published in 2008 and 2010, Karikó and Weissman showed that the delivery of mRNA generated with base modifications markedly increased protein production compared to unmodified mRNA. The effect was due to the reduced activation of an enzyme that regulates protein production.” That enzyme is PKR (protein kinase R), named in the 2010 paper’s title. When PKR senses suspicious RNA it halts the cell’s protein-making machinery, like the emergency stop button on a factory line; modified mRNA presses that button far less, so the cell keeps reading the message and makes more protein.

The three papers the committee named

None of the three was a study in people. The committee’s longer scientific background sums up the contribution in one sentence: “A turning point was the discovery by Karikó and Weissman demonstrating that mRNA produced with modified nucleoside bases evades innate immune recognition and improves protein expression.” It also records how the work was first received: “The results published by Karikó and Weissman in their seminal 2005 paper received little attention at the time but laid the foundation for critically important developments that have served humanity during the COVID-19 pandemic.”

Two more pieces sit on either side of the prize-winning papers. Before them, in 2004, the pair reported that test-tube mRNA acts on the sensor TLR3 — in the committee’s summary, that it “contains dsRNA contaminants that can activate TLR3” (dsRNA is double-stranded RNA, a hallmark of viruses; cell experiments). After them came the exact letter used in the COVID-19 vaccines: N1-methylpseudouridine (m1Ψ), a refined form of pseudouridine that another research group showed in 2015 outperformed pseudouridine in cells and mice. The background: “Later work showed that the use of N1-methylpseudouridine (m1Ψ), alone or in combination with m5C, further improved the mRNA platform both in terms of reducing recognition of innate immune receptors and increasing protein expression,” and “today, m1Ψ is the most common modified base used in mRNA vaccine production.” Both the Pfizer–BioNTech and the Moderna vaccines, it says, “had complete substitutions of uridine with N1-methylpseudouridine (m1Ψ) to avoid unwanted inflammatory responses, to ramp up protein translation, and to enable higher mRNA amounts to be used in each vaccine dose.” The prize rewards the principle; the precise letter in the vaccines was a later refinement that the committee’s own background credits to that later work.

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3. The Two Laureates

The committee’s short biographies, with dates from the laureates’ fact pages on nobelprize.org:

Katalin Karikó

Born on 17 January 1955 in Szolnok, Hungary. She received her PhD from the University of Szeged in 1982 and did postdoctoral research at the Hungarian Academy of Sciences in Szeged until 1985, then at Temple University in Philadelphia and, in the words of the committee’s background, at “the Uniformed Services University of the Health Sciences in Bethesda.” The press release continues: “In 1989, she was appointed Assistant Professor at the University of Pennsylvania, where she remained until 2013. After that, she became vice president and later senior vice president at BioNTech RNA Pharmaceuticals. Since 2021, she has been a Professor at Szeged University and an Adjunct Professor at Perelman School of Medicine at the University of Pennsylvania.” Her affiliation at the time of the award is listed as Szeged University and the University of Pennsylvania.

She became the thirteenth woman to receive the Nobel Prize in Physiology or Medicine. Counting from nobelprize.org’s own list of women laureates, the first was Gerty Cori in 1947 and the twelfth was Tu Youyou in 2015; since Karikó, Mary E. Brunkow has become the fourteenth, in 2025.

Drew Weissman

Born on 7 September 1959 in Lexington, Massachusetts. “He received his MD, PhD degrees from Boston University in 1987. He did his clinical training at Beth Israel Deaconess Medical Center at Harvard Medical School and postdoctoral research at the National Institutes of Health.” The committee’s background adds that at the NIH he joined Anthony Fauci’s group “to investigate how the human immunodeficiency virus type 1 (HIV-1) interacts with target receptors on different types of immune cells.” Then: “In 1997, Weissman established his research group at the Perelman School of Medicine at the University of Pennsylvania. He is the Roberts Family Professor in Vaccine Research and Director of the Penn Institute for RNA Innovations.”

How they met, in Karikó’s words

The committee describes a partnership of complementary skills: “With Weissman’s background in immunology and Karikó’s expertise in RNA biochemistry, the two scientists complemented each other well.” Weissman’s major goal, it notes, was “to develop a vaccine against HIV-1” (see our HIV/AIDS page). At the Nobel banquet, Karikó settled a much-repeated anecdote herself:

“The anecdote is true, we met at a xerox machine in the hallway of a Medical School building at the University of Pennsylvania in 1997. No, we didn’t wrestle with each other to get access to the copy machine, it is a made-up story. Instead, Drew and I started to work together, shoulder-to-shoulder through many decades.”

The longer personal story — leaving Hungary, the rejected grants, the demotion, the move to BioNTech — is told on the main Karikó & Weissman page.

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4. The Lectures and the Ceremony

The statutes ask every laureate, “whenever this is possible, to give a lecture on a subject relevant to the work for which the prize has been awarded.” Both laureates lectured on the same day, in the same hall.

The prizes were presented on 10 December 2023 at Konserthuset Stockholm, the Stockholm Concert Hall. The date is fixed by the statutes: 10 December, “the anniversary of the death of the testator,” is the day each prizewinner receives “a diploma and a gold medal bearing the image of the testator,” together with the prize money. The presentation speech for Physiology or Medicine was given by Professor Gunilla Karlsson Hedestam, a member of the Nobel Assembly and Chair of the Nobel Committee for Physiology or Medicine. Her account of the discovery:

“In a breakthrough discovery published in 2005, they demonstrated that mRNA produced with standard nucleotides evoked an undesired inflammatory response when delivered to human cells. They found that this reaction was circumvented when one of the four nucleotides was chemically modified to mimic our own mRNA. This finding provided a solution to a major problem previously facing mRNA-based clinical applications, propelling the mRNA technology into a new era.”

She closed, as these speeches do, by inviting the laureates “to step forward to receive the Nobel Prize from the hands of His Majesty the King.”

The prize money

The Nobel Foundation’s table of prize amounts lists SEK 11,000,000 (eleven million Swedish kronor) for a full prize in 2023. Karikó and Weissman held a share of one half each, so the sum was divided equally between them.

The banquet speech

At the Nobel banquet on the same day, Karikó spoke for both laureates. Her thanks included a sentence that belongs in any account of the credit question (Section 7):

“Importantly to us, this award also recognizes the fellow scientists who worked diligently over decades to help build the foundation for our work that led to the development of COVID-19 mRNA vaccines.”

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5. The Honours Before the Nobel

By the time the Nobel arrived, the same discovery had already been honoured by several of the world’s major science prizes. Each entry below is taken from the awarding body’s own website, with its citation in its own words. Notice how differently the juries drew the circle of credit — two names, seven names, three names.

The Gairdner choice speaks most directly to the question “who else?”: it named a pioneer of the delivery particle beside the discoverers of the modified letters. The Nobel statutes allow up to three names for one work (Section 7); the 2023 Nobel named two.

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6. A Nobel Rewards a Discovery, Not a Product

Read the citation’s grammar once more: the prize is “for their discoveries concerning nucleoside base modifications,” and the vaccines are what those discoveries “enabled.” That follows the will, which speaks of “the most important discovery within the domain of physiology or medicine.” A Nobel Prize is not a licence, a regulatory approval or a safety review of any product. Regulators such as the FDA and the European Medicines Agency do that work; the prize committee does not.

Why reward a 2005 paper in 2023? The statutes answer that too. The will’s phrase “during the preceding year” is to be understood as rewarding “the most recent achievements in the fields of culture referred to in the will and for older works only if their significance has not become apparent until recently.” The committee’s documents tell that story: a 2005 paper that “received little attention at the time,” whose importance showed when the vaccines built on it were tested and authorized in 2020.

What the committee wrote about the vaccines is the committee’s own statement, and it is quoted here as such:

“After the outbreak of the COVID-19 pandemic, two base-modified mRNA vaccines encoding the SARS-CoV-2 surface protein were developed at record speed. Protective effects of around 95% were reported, and both vaccines were approved as early as December 2020. … Several other vaccines against SARS-CoV-2, based on different methodologies, were also rapidly introduced, and together, more than 13 billion COVID-19 vaccine doses have been given globally. The vaccines have saved millions of lives and prevented severe disease in many more, allowing societies to open and return to normal conditions.”

Two details of that passage matter. The figure of more than 13 billion doses counts all COVID-19 vaccines, including those “based on different methodologies,” not only the two mRNA vaccines. And “around 95%” refers to the original phase 3 trials against symptomatic COVID-19, which the committee’s background gives as 95% and 94% for the two vaccines. How protection held up afterwards, and the documented harms, are set out with their sources on the main page’s sections The 2020 Trials — What Held, What Didn’t and The Safety Record, Honestly. This page does not repeat that record.

The committee’s background also notes that modified letters are not the only route. Some mRNA medicines now in trials “used unmodified bases,” and it expects “circular RNA, replicons and other types of RNA that do not contain base-modifications” to be developed. The prize honours the discovery that made the first licensed mRNA vaccines practical — before them, in the background’s words, “no mRNA-based vaccine had been approved for human use” — not a claim that every future mRNA product will depend on it.

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7. Who Else Built the mRNA Vaccines

A Nobel Prize can name at most three people. The statutes, verbatim: “If a work that is being rewarded has been produced by two or three persons, the prize shall be awarded to them jointly. In no case may a prize amount be divided between more than three persons.” Vaccines are built by many hands. Karikó’s own Nobel lecture begins by saying so: “Messenger RNA was discovered in 1961, and it took 60 years until the first mRNA became an FDA-approved product in the form of the COVID-19 mRNA vaccine. During those years, hundreds of scientists made a great deal of progress.” A 2021 Nature feature on the field’s history by the science journalist Elie Dolgin carries the same idea in its subtitle: “Hundreds of scientists had worked on mRNA vaccines for decades before the coronavirus pandemic brought a breakthrough.”

The clearest guide to who else contributed is the Nobel committee’s own scientific background, which names them. In the order the story unfolds:

The background’s opening paragraph lists the pieces together: “These findings, combined with the development of efficient systems for in vivo mRNA delivery, stabilization of the SARS-CoV-2 spike antigen, and unparalleled investments by industry and governments, led to the approval of two highly successful mRNA-based COVID-19 vaccines in late 2020.”

What the people involved have said

Karikó ended her Nobel lecture: “And, finally, I would like to acknowledge the efforts of all the scientists working diligently for decades to help build the foundation for our work that led to the development of COVID-19 mRNA vaccines.” Her banquet speech, quoted in Section 4, said the same. Others have spoken for their own contributions. Dr. Robert Malone, first author of the 1989 paper, has a website whose history page, written by his wife Jill Malone, states: “Dr. Malone is the inventor of mRNA vaccines (and DNA vaccines). He also discovered lipid-mediated and naked RNA transfection technologies.” The Nobel committee’s background cites the 1989 paper among the field’s foundations.

Whether anyone else was nominated, or considered and set aside, is not public: under statute §10 the proposals and the committee’s investigations stay closed for at least 50 years after the decision. What the open record shows is the pattern above — the same achievement honoured by different juries with two, three or seven names, and a Nobel citation that names exactly the discovery it rewards.

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8. The Nobel Prizes Behind This One

The 2023 prize is the latest link in a chain of Nobel-winning discoveries, and the committee’s own documents point to several of them.

1951 — Max Theiler: the “before” picture

The press release begins its history with traditional vaccines: “Vaccines based on killed or weakened viruses have long been available, exemplified by the vaccines against polio, measles, and yellow fever. In 1951, Max Theiler was awarded the Nobel Prize in Physiology or Medicine for developing the yellow fever vaccine.” It then names the limitation a test-tube-made mRNA vaccine avoids: “Producing whole virus-, protein- and vector-based vaccines requires large-scale cell culture. This resource-intensive process limits the possibilities for rapid vaccine production in response to outbreaks and pandemics.” Theiler’s own citation reads “for his discoveries concerning yellow fever and how to combat it.” Our page: Max Theiler.

1965 — Jacob, Lwoff and Monod: the idea of a messenger

The committee chair drew this link herself in the 2023 presentation speech: “Messenger RNA was first defined by Jacob and Monod in 1961, a discovery that was awarded a Nobel Prize in Physiology or Medicine in 1965.” That prize went to François Jacob, André Lwoff and Jacques Monod “for their discoveries concerning genetic control of enzyme and virus synthesis.” Our page: Jacob, Lwoff & Monod.

1968 — Holley, Khorana and Nirenberg: reading the code, with a snake-venom enzyme

Robert Holley, Har Gobind Khorana and Marshall Nirenberg shared the 1968 prize “for their interpretation of the genetic code and its function in protein synthesis” — how a string of RNA letters, read three at a time, spells out a protein. Every mRNA vaccine is a message written in that code: its letters spell out the spike protein, which the body’s cells build, in the 2023 presentation speech’s words, “for a short while.”

This prize also touches the question that brings many readers to these pages. Snake venom phosphodiesterase — an enzyme that chews RNA or DNA one letter at a time from one end — was one of the standard tools of that era’s RNA chemistry. Khorana and his colleague W. E. Razzell described its properties in 1959 (test-tube biochemistry). Holley’s own Nobel lecture, “Alanine Transfer RNA,” describes how it helped determine the first RNA sequence ever read, published in 1965 (test-tube chemistry): “One new method that was especially useful is outlined in Figs. 5 and 6. As indicated in Fig. 5, partial digestion of an oligonucleotide with snake venom phosphodiesterase gives a mixture of degradation products.” The enzyme was a routine laboratory reagent decades before Karikó and Weissman began their work. Our pages: Nirenberg, Khorana & Holley and Snake Venom Phosphodiesterase in the Karikó–Weissman Papers.

2006 — Fire and Mello: double-stranded RNA, and a delivery particle

Andrew Fire and Craig Mello won “for their discovery of RNA interference – gene silencing by double-stranded RNA”: cells that meet double-stranded RNA silence the matching gene. Two threads run from that prize to the vaccines. First, double-stranded RNA is also what Karikó and Weissman found contaminating test-tube mRNA, where it sets off the TLR3 and PKR alarms; in 2011 they showed that a purification step (HPLC) that removes it eliminated the remaining immune activation and improved protein production (cell experiments). Second, the first medicine built on RNA interference reached patients inside the same kind of particle the vaccines use. Patisiran, approved by the FDA in 2018, is described on its label as “a double-stranded small interfering ribonucleic acid (siRNA), formulated as a lipid complex for delivery to hepatocytes,” and the label lists cholesterol, DSPC, a PEG lipid and a lipid called DLin-MC3-DMA — the same four kinds of ingredient the committee’s background describes for the lipid nanoparticle, and that the COVID-19 mRNA vaccine labels list with their own lipids (quoted on our From Pseudouridine to the COVID-19 Vaccines page). Our page: Fire & Mello.

2011 — Beutler, Hoffmann and Steinman: the alarms and the sentries

This is the prize closest to the 2023 discovery. One half went to Bruce Beutler and Jules Hoffmann “for their discoveries concerning the activation of innate immunity,” the other half to Ralph Steinman “for his discovery of the dendritic cell and its role in adaptive immunity.” The 2011 press release explains that Hoffmann found in 1996 that fruit flies need a gene called Toll to fight infection, and that in 1998 Beutler found its counterpart in mice, a “Toll-like receptor”; Steinman, according to his nobelprize.org biography, discovered the dendritic cell in 1973. Those are precisely the tools of the 2005 experiment: Karikó and Weissman measured how Toll-like receptors (TLR3, TLR7 and TLR8) and dendritic cells react to RNA, and showed that modified letters keep those alarms quiet. The 2023 background names the link itself: “Ralph Steinman was awarded a Nobel Prize in Physiology or Medicine for the discovery of dendritic cells in 2011.” (Steinman died on 30 September 2011; nobelprize.org records that “The Nobel Assembly was unaware that Steinman had died of cancer three days earlier when it decided to award him the Nobel Prize.”) Our page: Beutler, Hoffmann & Steinman.

Three of these prizes line up as a single chain of questions and answers. The picture below sets them side by side.

Three boxes joined by arrows. The 1968 Nobel Prize explained how the genetic code is read, and the vaccine mRNA is a message written in that code. The 2011 prize found the immune alarms (Toll-like receptors) and the dendritic cell, which unmodified lab-made mRNA sets off. The 2023 prize showed that modified RNA letters keep those alarms quiet, and both COVID-19 mRNA vaccines replace every uridine with N1-methylpseudouridine. Below, a timeline marks the 2005 paper, the vaccines authorized in 2020 and the prize in 2023: 15 years from paper to pandemic and 18 years from paper to prize. THREE NOBEL PRIZES IN ONE VACCINE Each prize answers a question the next one needed — and the 2023 prize rewarded a 2005 paper 1968 Holley · Khorana · Nirenberg THE DISCOVERY How the genetic code is read: three RNA letters name one amino acid WHY IT MATTERS The vaccine mRNA is a message in that code: it spells out the spike protein, which your cells build for a short while 2011 Beutler · Hoffmann · Steinman THE DISCOVERY Sensors that sound the first alarm (Toll-like receptors) and the dendritic cell WHY IT MATTERS Unmodified lab-made mRNA trips these alarms (TLR3, TLR7, TLR8) in dendritic cells: inflammation and poor protein production 2023 THIS PRIZE Karikó · Weissman THE DISCOVERY Modified RNA letters, like those in our own cells, keep those alarms quiet WHY IT MATTERS Both COVID-19 mRNA vaccines replace every uridine (U) with N1-methylpseudouridine, a refined form of pseudouridine THE TIME LAG 15 years: paper to pandemic 2005 · the Immunity paper 2023 · Nobel Prize 2020 · two mRNA vaccines authorized 18 years: paper to prize

Read the boxes left to right: the 1968 prize explains how the message is written, the 2011 prize explains why the body attacked lab-made messages, and the 2023 prize explains how Karikó and Weissman made the message pass; the strip underneath shows the 15 years from the 2005 paper to the pandemic and the 18 years from the paper to the prize in 2023.

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9. Questions Readers Ask

Did the Nobel Prize mention snake venom?

Dr. Bryan Ardis has said of Karikó and Weissman’s papers, in a May 2025 podcast interview (Culture Apothecary with Alex Clark): “in every one of those research studies, they state snake venom phosphodiesterase.” Here is what the Nobel documents themselves contain, searched word by word on 3 October 2026:

The papers’ own sentences, side by side with Dr. Ardis’s words, are on our Snake Venom Phosphodiesterase page; his account of the D-dimer blood test is on D-Dimer and Snake Venom: Dr. Ardis on Blood Clots After Vaccination.

Was the prize for the COVID-19 vaccine?

Not in so many words. The citation rewards “discoveries concerning nucleoside base modifications” and describes the vaccines as what those discoveries “enabled.” The press release’s next sentence states the connection directly: “The discoveries by the two Nobel Laureates were critical for developing effective mRNA vaccines against COVID-19 during the pandemic that began in early 2020.” The vaccines themselves were designed, tested and manufactured by companies working with government and university laboratories (Section 7).

Who nominated them, and who else was considered?

Nobody outside the Nobel institutions can say yet. Under statute §10, nominations, investigations and opinions “may not be divulged,” and access to them may not be given “until at least 50 years have elapsed from the date of the relevant prize decision” — for this prize, no earlier than 2073.

Why only two people?

The statutes allow up to three people for one work; how the committee drew the line is part of the closed record. Other juries made different choices for the same achievement: the Gairdner Foundation added Pieter Cullis, and the Princess of Asturias Foundation named seven scientists (Section 5).

How much money did they receive?

The full 2023 prize was SEK 11 million, divided equally, with a gold medal and a diploma for each laureate.

Where did the money for their research come from?

The Nobel documents do not discuss research funding; the papers’ acknowledgements do. The 2008 paper’s reads: “This work was supported by the National Institutes of Health (NIH) grants NIAID AI-050484, NHLBI HL87688, and NINDS NS-29331.” Dr. Ardis has described the pair as “funded by the NIH starting in 2009 to develop these COVID-19 mRNA vaccines.” The NIH’s own project database, RePORTER, lists the grants on which Karikó or Weissman was principal investigator, with titles ranging from HIV vaccines and microbicides to an mRNA treatment for anemia, gene editing for hemophilia A and an mRNA vaccine against Clostridioides difficile; none of the listed project titles names SARS-CoV-2 or COVID-19 (RePORTER lists principal-investigator awards only). The committee’s background dates the virus’s emergence to “late 2019.” The full list, with dates and amounts, is on our NIH Grants page, and the papers one by one are on Karikó and Weissman’s Research, Paper by Paper.

Can a Nobel decision be appealed?

No. Statute §10: “No appeals may be made against the decision of a prize-awarding body with regard to the award of a prize.”

Is the prize a verdict on the vaccines’ safety?

No. The committee’s documents describe the vaccines’ benefits and, briefly, their safety, but the prize rewards a discovery; it is not a regulatory review. The site’s full benefit-and-harm record, with sources, is on the main page: the trials and the safety record.

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Key Research Papers

  1. Karikó K, Buckstein M, Ni H, Weissman D (2005). Suppression of RNA recognition by Toll-like receptors: the impact of nucleoside modification and the evolutionary origin of RNA. Immunity. — PubMed PMID: 16111635
  2. Karikó K, Muramatsu H, Welsh FA, et al. (2008). Incorporation of pseudouridine into mRNA yields superior nonimmunogenic vector with increased translational capacity and biological stability. Mol Ther. — PubMed PMID: 18797453
  3. Anderson BR, Muramatsu H, Nallagatla SR, et al. (2010). Incorporation of pseudouridine into mRNA enhances translation by diminishing PKR activation. Nucleic Acids Res. — PubMed PMID: 20457754
  4. Karikó K, Ni H, Capodici J, et al. (2004). mRNA is an endogenous ligand for Toll-like receptor 3. J Biol Chem. — PubMed PMID: 14729660
  5. Karikó K, Muramatsu H, Ludwig J, Weissman D (2011). Generating the optimal mRNA for therapy: HPLC purification eliminates immune activation and improves translation of nucleoside-modified, protein-encoding mRNA. Nucleic Acids Res. — PubMed PMID: 21890902
  6. Andries O, Mc Cafferty S, De Smedt SC, et al. (2015). N(1)-methylpseudouridine-incorporated mRNA outperforms pseudouridine-incorporated mRNA by providing enhanced protein expression and reduced immunogenicity in mammalian cell lines and mice. J Control Release. — PubMed PMID: 26342664
  7. Razzell WE, Khorana HG (1959). Studies on polynucleotides. III. Enzymic degradation; substrate specificity and properties of snake venom phosphodiesterase. J Biol Chem. — PubMed PMID: 13673021
  8. Holley RW, Apgar J, Everett GA, et al. (1965). Structure of a ribonucleic acid. Science. — PubMed PMID: 14263761
  9. Malone RW, Felgner PL, Verma IM (1989). Cationic liposome-mediated RNA transfection. Proc Natl Acad Sci U S A. — PubMed PMID: 2762315
  10. Wolff JA, Malone RW, Williams P, et al. (1990). Direct gene transfer into mouse muscle in vivo. Science. — PubMed PMID: 1690918
  11. Pallesen J, Wang N, Corbett KS, et al. (2017). Immunogenicity and structures of a rationally designed prefusion MERS-CoV spike antigen. Proc Natl Acad Sci U S A. — PubMed PMID: 28807998
  12. Wrapp D, Wang N, Corbett KS, et al. (2020). Cryo-EM structure of the 2019-nCoV spike in the prefusion conformation. Science. — PubMed PMID: 32075877
  13. Hou X, Zaks T, Langer R, Dong Y (2021). Lipid nanoparticles for mRNA delivery. Nat Rev Mater. — PubMed PMID: 34394960
  14. Dolgin E (2021). The tangled history of mRNA vaccines. Nature. — PubMed PMID: 34522017

PubMed Topic Searches

  1. PubMed: Nucleoside-modified mRNA and Toll-like receptors
  2. PubMed: N1-methylpseudouridine in mRNA vaccines
  3. PubMed: History of mRNA vaccines

External Authoritative Resources

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Connections

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