Skip to content
  • Home Home Home, current page.
  • Moments Moments Moments, current page.

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @
  • Language: English
    • Bahasa Indonesia
    • Bahasa Melayu
    • Català
    • Čeština
    • Dansk
    • Deutsch
    • English UK
    • Español
    • Filipino
    • Français
    • Hrvatski
    • Italiano
    • Magyar
    • Nederlands
    • Norsk
    • Polski
    • Português
    • Română
    • Slovenčina
    • Suomi
    • Svenska
    • Tiếng Việt
    • Türkçe
    • Ελληνικά
    • Български език
    • Русский
    • Српски
    • Українська мова
    • עִבְרִית
    • العربية
    • فارسی
    • मराठी
    • हिन्दी
    • বাংলা
    • ગુજરાતી
    • தமிழ்
    • ಕನ್ನಡ
    • ภาษาไทย
    • 한국어
    • 日本語
    • 简体中文
    • 繁體中文
  • Have an account? Log in
    Have an account?
    · Forgot password?

    New to Twitter?
    Sign up
chasewnelson's profile
Chase W. Nelson 倪誠志
Chase W. Nelson 倪誠志
Chase W. Nelson 倪誠志
@chasewnelson

Tweets

Chase W. Nelson 倪誠志

@chasewnelson

Research Fellow @NIH @theNCI @AMNH 🇺🇸 • #bioinformatics #cancer #evolution #Taiwan 🇹🇼 #viruses • Singer • Writer • he/他 🏳️‍🌈 • views my own • 🧬🎵🏋📚☕️

Taipei, Taiwan 台灣台北
linkedin.com/in/chasewnelso…
Joined March 2012

Tweets

  • © 2022 Twitter
  • About
  • Help Center
  • Terms
  • Privacy policy
  • Cookies
  • Ads info
Dismiss
Previous
Next

Go to a person's profile

Saved searches

  • Remove
  • In this conversation
    Verified accountProtected Tweets @
Suggested users
  • Verified accountProtected Tweets @
  • Verified accountProtected Tweets @

Promote this Tweet

Block

  • Tweet with a location

    You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more

    Your lists

    Create a new list


    Under 100 characters, optional

    Privacy

    Copy link to Tweet

    Embed this Tweet

    Embed this Video

    Add this Tweet to your website by copying the code below. Learn more

    Add this video to your website by copying the code below. Learn more

    Hmm, there was a problem reaching the server.

    By embedding Twitter content in your website or app, you are agreeing to the Twitter Developer Agreement and Developer Policy.

    Preview

    Why you're seeing this ad

    Log in to Twitter

    · Forgot password?
    Don't have an account? Sign up »

    Sign up for Twitter

    Not on Twitter? Sign up, tune into the things you care about, and get updates as they happen.

    Sign up
    Have an account? Log in »

    Two-way (sending and receiving) short codes:

    Country Code For customers of
    United States 40404 (any)
    Canada 21212 (any)
    United Kingdom 86444 Vodafone, Orange, 3, O2
    Brazil 40404 Nextel, TIM
    Haiti 40404 Digicel, Voila
    Ireland 51210 Vodafone, O2
    India 53000 Bharti Airtel, Videocon, Reliance
    Indonesia 89887 AXIS, 3, Telkomsel, Indosat, XL Axiata
    Italy 4880804 Wind
    3424486444 Vodafone
    » See SMS short codes for other countries

    Confirmation

     

    Welcome home!

    This timeline is where you’ll spend most of your time, getting instant updates about what matters to you.

    Tweets not working for you?

    Hover over the profile pic and click the Following button to unfollow any account.

    Say a lot with a little

    When you see a Tweet you love, tap the heart — it lets the person who wrote it know you shared the love.

    Spread the word

    The fastest way to share someone else’s Tweet with your followers is with a Retweet. Tap the icon to send it instantly.

    Join the conversation

    Add your thoughts about any Tweet with a Reply. Find a topic you’re passionate about, and jump right in.

    Learn the latest

    Get instant insight into what people are talking about now.

    Get more of what you love

    Follow more accounts to get instant updates about topics you care about.

    Find what's happening

    See the latest conversations about any topic instantly.

    Never miss a Moment

    Catch up instantly on the best stories happening as they unfold.

    Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

    TODAY at #Virological: throughout the #COVID19 pandemic, there has been a tendency to underestimate the potential of #SARSCoV2 to mutate and adapt. As the @US_FDA meets Tuesday to discuss #molnupiravir, @sarperotto and I fear another oversight.🧵 1/15https://virological.org/t/mutagenic-antivirals-the-evolutionary-risk-of-low-doses/768 …

    11:21 PM - 28 Nov 2021
    • 22 Retweets
    • 63 Likes
    • nuvolina22 💉💉💉😷 D̊⫶Λ̊⫶Ƨ̊⫶ Jim Reynolds (James L Reynolds) Silvana Konermann Real Chain Insights ⚔️ Eliz Moncada Holtz Darklordmtt Federico Gueli
    3 replies 22 retweets 63 likes
      1. New conversation
      2. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        To be clear, I believe vaccines and antiviral drugs BOTH have critical parts to play in the fight against #COVID19. Oral antivirals are of particular interest given their potential for equitable distribution. This is NOT an argument against antivirals. 2/15

        1 reply 1 retweet 9 likes
        Show this thread
      3. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        Antivirals can work via several mechanisms. 🦠PROTEASE INHIBITORS, like #paxlovid and #masitinib, prevent the production of mature viral proteins. 🧬MUTAGENS, like #molnupiravir, instead increase the viral mutation rate to intolerable levels, causing LETHAL MUTAGENESIS. 3/15

        1 reply 6 retweets 16 likes
        Show this thread
      4. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        Critically, any self-administered drug risks low concentrations due to missed doses, incomplete courses, or low initial penetrance. For #molnupiravir, this might induce only SUBLETHAL MUTAGENESIS, accelerating within-host virus evolution and potentiating new variants. 4/15

        2 replies 1 retweet 10 likes
        Show this thread
      5. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        The risk of mutagens is underscored by the fact that another antiviral, #ribavirin, induces adaptive mutations in other RNA viruses. Moreover, past #SARSCoV2 variants of concern likely acquired adaptive combinations of mutations during chronic infections before transmitting. 5/15

        1 reply 2 retweets 9 likes
        Show this thread
      6. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        Given the potential for SUBLETHAL MUTAGENESIS of #SARSCoV2 by #molnupiravir, steps should be taken to understand the evolutionary consequences of low drug concentrations and improper administration for pathogen evolution. Below is a list of issues to consider.👇 6/15

        1 reply 2 retweets 9 likes
        Show this thread
      7. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        1⃣ Because #molnupiravir will be taken by patients with recent symptom onset, and drug concentration increases from 0 over time, PEAK VIRAL SHEDDING is likely to occur while drug concentration is still low. This could potentiate the shedding of mutant — but viable — virus. 7/15

        1 reply 1 retweet 9 likes
        Show this thread
      8. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        2⃣ #Molnupiravir has a SHORT PLASMA HALF-LIFE, making low concentrations easier to achieve, say, as a result of missed or inconsistently timed doses. 8/15

        2 replies 1 retweet 9 likes
        Show this thread
      9. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        3⃣ Coronaviruses have a propensity for RECOMBINATION, which can help purge viral genomes of deleterious mutations, or generate adaptive combinations of beneficial or compensatory mutations. These phenomena are therefore critical to include in models and simulations. 9/15

        1 reply 1 retweet 11 likes
        Show this thread
      10. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        4⃣ #SARSCoV2 has a PRE-EXISTING BIAS for C→U mutations — the main mutation caused by #molnupiravir — as well as a genomic G:C content of 38%, and a plus-strand C content of 18%. These characteristics limit the extent to which molnupiravir can raise the mutation rate. 10/15

        1 reply 1 retweet 8 likes
        Show this thread
      11. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        5⃣ Epidemiological spread of adaptive mutations is limited by both: (a) their GENERATION VIA MUTATION within hosts; and (b) the TRANSMISSION BOTTLENECK SIZE between hosts, that is, the number of viral genomes that found a new infection. 11/15

        1 reply 1 retweet 6 likes
        Show this thread
      12. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        6⃣ Even if the average number of mutations per viral genome is high, the DISTRIBUTION OF MUTATION COUNTS can still include a class of minimally mutated viable genomes. This could be due to the mutation mechanism or ‘compartments’ with low drug concentrations within a host. 12/15

        1 reply 1 retweet 7 likes
        Show this thread
      13. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        7⃣ The MUTATIONAL ROBUSTNESS of #SARSCoV2 is not known. The highest mutation rate tolerated by a virus, just possibly 1-5 per replication per genome, depends on the size of the functional genome and the expendability of ‘accessory’ genes. 13/15

        1 reply 1 retweet 6 likes
        Show this thread
      14. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        EVERYONE must understand the importance of taking #molnupiravir as directed, and of quarantining while doing so, as the above issues are studied. We must ensure that #SARSCoV2 is not inadvertently handed mutational resources for the accelerated generation of new variants. 14/15pic.twitter.com/23x0Cmow4z

        Pixabay
        1 reply 3 retweets 17 likes
        Show this thread
      15. Chase W. Nelson 倪誠志‏ @chasewnelson 28 Nov 2021

        🙏THANKS to coauthor @sarperotto and all who generously gave feedback: @zachary_ardern, @AprilWei001, @GoldbergTony, @jbloom_lab, and @RJABuggs, who first raised this issue to me on October 6 and provided invaluable insight and edits. All views and any errors are our own. 15/15

        1 reply 1 retweet 18 likes
        Show this thread
      16. Chase W. Nelson 倪誠志‏ @chasewnelson 3 Dec 2021

        Chase W. Nelson 倪誠志 Retweeted Chase W. Nelson 倪誠志

        🚨UPDATE on #MOLNUPIRAVIR. Below is a review of the @US_FDA materials and November 30 panel discussion on the potential for this drug to cause new #SARSCoV2 variants of concern. Overall, the panel voted in favor of authorization, 13 YES✅ to 10 NO❌. 👇https://twitter.com/chasewnelson/status/1466331830345293827 …

        Chase W. Nelson 倪誠志 added,

        Chase W. Nelson 倪誠志 @chasewnelson
        🧵The @US_FDA's materials on @Merck's #Molnupiravir and its potential to induce problematic #SARSCoV2 variants are HERE: 📄section 4.3.2.5 (pp. 30-36) 👉https://www.fda.gov/media/154418/download … 📺at 2h51m, 3h46m, 4h5m, 5h12m, 7h32m 👉https://youtu.be/fR9FNSJT64M  Observations to follow. 1/n
        Show this thread
        1 reply 1 retweet 5 likes
        Show this thread
      17. Chase W. Nelson 倪誠志‏ @chasewnelson 5 Dec 2021

        Chase W. Nelson 倪誠志 Retweeted Chase W. Nelson 倪誠志

        Some conceptual figures illustrating our concerns are here👇https://twitter.com/chasewnelson/status/1466722854876377093 …

        Chase W. Nelson 倪誠志 added,

        Chase W. Nelson 倪誠志 @chasewnelson
        Despite 13-10 recommendation by the @US_FDA panel, we remain concerned the mutagenic drug #Molnupiravir could generate #SARSCoV2 variants. One reason: high viral shedding occurs when drug concentration is still low. The released virus could have a tolerable number of mutations. https://twitter.com/chasewnelson/status/1465219400064122882 … pic.twitter.com/xQtHDbaaA0
        Show this thread
        1 reply 2 retweets 5 likes
        Show this thread
      18. Chase W. Nelson 倪誠志‏ @chasewnelson 9 Dec 2021

        Chase W. Nelson 倪誠志 Retweeted Chase W. Nelson 倪誠志

        Additional insights from @LauringLab and others on whether the mutation-inducing antiviral #molnupiravir could accelerate #SARSCoV2 variants of concern👇https://twitter.com/chasewnelson/status/1468164091814748161 …

        Chase W. Nelson 倪誠志 added,

        Chase W. Nelson 倪誠志 @chasewnelson
        Great thread on #molnupiravir from @LauringLab, an expert in lethal mutagenesis.👇 I think all agree: 1) lack of data makes it hard to quantify the risk the drug will accelerate variants 2) IF taking the drug, patients should strictly isolate and strictly take ALL doses. 1/n https://twitter.com/LauringLab/status/1467861151983673349 …
        Show this thread
        1 reply 1 retweet 1 like
        Show this thread
      19. Chase W. Nelson 倪誠志‏ @chasewnelson 16 Dec 2021

        🦠💊UPDATE on #Molnupiravir: paper out in @NEJM. One sentence addresses the concern that its poorly characterized mutagenicity could accelerate virus evolution: "The mechanism of action of molnupiravir is independent of mutations in the spike protein..." https://twitter.com/NEJM/status/1471604809396482048 …pic.twitter.com/mKfMYy3vSI

        1 reply 0 retweets 2 likes
        Show this thread
      20. Chase W. Nelson 倪誠志‏ @chasewnelson 16 Dec 2021

        It is correct that the drug should work the same regardless of Spike genotype. A false interpretation is that molnupiravir doesn't mutate Spike. It does, along with the rest of the genome. Thus, I believe we still have only two relevant data summaries from Merck:

        1 reply 0 retweets 2 likes
        Show this thread
      21. Chase W. Nelson 倪誠志‏ @chasewnelson 16 Dec 2021

        1⃣ Merck reports a mean of ~7.5 mutations at a within-patient frequency of >5% across the virus genome. Note the range includes *0*. Note too this is within-host diversity (polymorphism) filtered by selection, not a mutation rate.pic.twitter.com/HE3xdk17e9

        1 reply 0 retweets 1 like
        Show this thread
      22. Chase W. Nelson 倪誠志‏ @chasewnelson 16 Dec 2021

        2⃣ Merck provides this chart, also difficult to interpret, but again likely referring to within-host variants at >5% frequency. Note that Baseline and Day 5 distributions *overlap*. More is needed, including raw sequence data, to estimate virus mutation and onward transmission.pic.twitter.com/P1OJgGwwjj

        1 reply 1 retweet 1 like
        Show this thread
      23. End of conversation

    Loading seems to be taking a while.

    Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.

      Promoted Tweet

      false

      • © 2022 Twitter
      • About
      • Help Center
      • Terms
      • Privacy policy
      • Cookies
      • Ads info