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Friday, January 1, 2021

Analyzing the vast coronavirus literature with CoronaCentral

 

Jake LeverRuss B. Altman

COVID-19 in Patients with Hematological Malignancies: High False Negative Rate + High Mortality

 lex Niu, MD1, Bo Ning, PhD2*, Francisco Socola, MD1, Hana Safah, MD1, Tim Reynolds1*, Moayed Ibrahim, MD1, Firas Safa, MD1, Tina Alfonso1*, Alfred Luk, MD3*, David M Mushatt, MD3*, Tony Hu, PhD2* and Nakhle S. Saba, MD1

1Section of Hematology and Medical Oncology, Department of Medicine, Tulane University, New Orleans, LA
2Department of Biochemistry & Molecular Biology, Tulane University, New Orleans, LA
3Section of Infectious Disease, Department of Medicine, Tulane University, New Orleans, LA

Patients with hematological malignancies (HM) are uniquely immunocompromised and considered at high risk for COVID-19. However, data regarding the diagnosis, clinical course, treatment, and outcomes of these patients is sparse. In particular, the ability to successfully detect SARS-CoV-2 in patients with HM remains unknown. We have previously reported 2 cases of allogeneic stem cell transplant (SCT) diagnosed with COVID-19 using clustered regularly interspaced short palindromic repeats (CRISPR) technique, following multiple negative nasopharyngeal RT-PCR testing (Niu et al. Bone Marrow Transplantation - Nature). Here we examine 29 patients with a variety of HM with high suspicion for COVID-19 based on clinical presentation, lab results, and imaging, whom were tested with CRISPR and/or RT-PCR based techniques. From 3/31/20 to 7/17/20, 29 patients (age 24 to 82) with a variety of HM (20 lymphoid, 9 myeloid; Table 1), 24 of which presented with an undiagnosed respiratory illness and 5 presented while asymptomatic for testing prior to chemotherapy, were evaluated for COVID-19. While 16 patients tested positive for COVID-19 with guideline-directed nasopharyngeal RT-PCR testing (including the 5 asymptomatic patients), 13 patients tested negative with the same technique. However, based on their clinical history, imaging, and disease course, concern for COVID-19 infection remained in these 13 patients. We then used CRISPR technology available at our institution (Huang et al. Biosensors and Bioelectronics) to test 8 patients who initially tested negative by RT-PCR. Surprisingly, 7 of the 8 patients tested positive for COVID-19 with either a blood sample and/or nasal swab for the SARS-CoV-2 specific N gene and ORF1ab gene. Excluding the patients who were negative by RT-PCR and not tested by CRISPR, the rate of false negativity with RT-PCR testing is significantly elevated at 29% (7/24) in our cohort of HM, which compares unfavorably with the expected false negative rates of RT-PCR techniques.

A very high fatality rate was observed with 9 out of the 29 patients (31%) ultimately dying. Fifteen patients were undergoing active chemotherapy, 4 had received an autologous SCT, 6 had received an allogeneic SCT, and 4 were on surveillance. Of the 23 COVID-19 positive patients (by RT-PCR or CRISPR), 8 patients received COVID-19-directed therapy with either hydroxychloroquine/azithromycin, remdesivir, and/or Covid-19 convalescent plasma (CCP) depending on their clinical status, and 4 patients expired. Of the 8 treated patients, 7 improved while 1 patient expired. For the 5 patients who were negative for RT-PCR with no CRISPR completed, 1 patient received hydroxychloroquine/azithromycin proactively due to symptoms and imaging and recovered, while 3 patients expired at outside facilities due to unknown causes. Breakdown of testing and treatment is shown in Fig. 1.

The majority of our patients had undergone SCT or were actively on chemotherapy, notably lymphodepleting chemotherapy. Associated with the fact that COVID-19 is known to worsen lymphopenia, our patient’s symptoms and immune response to COVID-19 is likely to differ from immunocompetent hosts. This translated into an overall worse outcome as seen by the high mortality with our patients. In our limited dataset, patients presented with a variety of symptoms ranging from asymptomatic to acute respiratory failure. Intriguingly, the 5 asymptomatic patients had lymphoid malignancies and were on chemotherapy.

It is thus imperative to establish the diagnosis of COVID-19 quickly, as faster initiation of treatment has been associated with better outcomes. The 8 patients who were diagnosed and treated improved substantially. However, as seen by our dataset, a strikingly high false negative rate was observed. Thus, a high clinical suspicion must guide further workup and therapy in patients with HM who present with an undiagnosed respiratory illness consistent with COVID-19. Patients with HM can have a wide variety of presentations when infected with COVID-19. For this select patient population we must establish an algorithm to diagnose COVID-19 efficiently as we reported a high number of initial false negative COVID-19 tests before the more sensitive CRISPR revealed a positive test. In addition, treatment pathways need to be instituted to not only treat COVID-19 infection, but also provide the best treatment for these patient’s underlying HM.

https://ash.confex.com/ash/2020/webprogram/Paper138611.html

Why is COVID-19 less severe in children?

 

  • Petra Zimmermann1,2,3
  • Nigel Curtis3,4,5


  • PDF: https://adc.bmj.com/sites/default/themes/bmjj/img/icon-pdf.png

    Abstract

    In contrast to other respiratory viruses, children have less severe symptoms when infected with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this review, we discuss proposed hypotheses for the age-related difference in severity of coronavirus disease 2019 (COVID-19).

    Factors proposed to explain the difference in severity of COVID-19 in children and adults include those that put adults at higher risk and those that protect children. The former include: (1) age-related increase in endothelial damage and changes in clotting function; (2) higher density, increased affinity and different distribution of angiotensin converting enzyme 2 receptors and transmembrane serine protease 2; (3) pre-existing coronavirus antibodies (including antibody-dependent enhancement) and T cells; (4) immunosenescence and inflammaging, including the effects of chronic cytomegalovirus infection; (5) a higher prevalence of comorbidities associated with severe COVID-19 and (6) lower levels of vitamin D. Factors that might protect children include: (1) differences in innate and adaptive immunity; (2) more frequent recurrent and concurrent infections; (3) pre-existing immunity to coronaviruses; (4) differences in microbiota; (5) higher levels of melatonin; (6) protective off-target effects of live vaccines and (7) lower intensity of exposure to SARS-CoV-2.

    https://adc.bmj.com/content/early/2020/11/30/archdischild-2020-320338

    SARS-CoV-2-specific T cell memory long-lasting in majority of convalsecent COVID-19 individuals

     Ziwei Li, Jing Liu, Hui Deng, Xuecheng Yang, Hua Wang, Xuemei Feng, Gennadiy Zelinskyy, Mirko Trilling, Kathrin Sutter, Mengji Lu, Ulf Dittmer, Baoju Wang, Dongliang Yang, Xin Zheng, Jia Liu

    Messengers of hope

     Emergency Use Authorizations for two mRNA COVID-19 vaccines represent a turning point in the pandemic. They also herald a new era for vaccinology.

    One year ago, few would have tipped mRNA vaccines as the world’s best hope. They had been tested in a handful of human trials. They had been injected into fewer than 1,800 people. And efficacy data in humans were both sparse and underwhelming. Twelve months on, ~34,000 people have received mRNA immunizations in human trials of two mRNA products targeting SARS-CoV-2 spike (S) protein. Both products provide impressive efficacy, notably in individuals 65 or older. Emergency Use Authorizations of BioNTech/Pfizer’s BNT162b2 and Moderna’s mRNA-1273 vaccines raise hopes that the pandemic could finally turn a corner. They may even presage an era where vaccines are designed in computers, iteratively optimized in discovery and manufactured on demand — all without expensive and finicky cell culture.

    The new nucleoside-modified mRNA vaccines are chemicals that have been almost fully disclosed. They incorporate a trinucleotide cap 1 analog ((m27,3′-O)Gppp(m2′-O)ApG), contain N1-methylpseudouridine instead of uridine, and encode an optimized (P2-mutated) full-length S glycoprotein encapsulated in lipid nanoparticles (LNPs) containing polyethylene glycol and cholesterol. The BNT162b2 LNP also contains (4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate) and 1,2-distearoyl-sn-glycero-3-phosphocholine, whereas Moderna’s LNP contains SM-102 (most likely heptadecan-9-yl 8-((2-hydroxyethyl)(6-oxo-6-(undecyloxy)hexyl)amino)octanoate) and 1,2-dimyristoyl-rac-glycero-3-methoxypolyethylene glycol-2000 (PEG). The BioNTech vaccine is administered intramuscularly (IM) as two 30-μg doses 21 days apart, the Moderna product as two 100-μg IM doses 28 days apart.

    Two other types of synthetic mRNA LNP COVID-19 vaccines have also entered testing: CureVac just initiated a phase 2/3 trial for its unmodified uridine-deficient mRNA product (CVnCoV), and during the summer Arcturus Therapeutics and Imperial College London commenced phase 1 testing of self-amplifying RNA vaccines based on an alphavirus that encode non-structural proteins to replicate the S-protein immunogen.

    The BioNTech and Moderna vaccines work spectacularly. Of the 20,033 people who received BNT162b2, efficacy outcomes one week after the second dose were 95%, a level consistent (≥93%) across all demographic subgroups. In the 13,218 participants receiving two doses of Moderna’s vaccine, efficacy was 93.4% for people 18 to 64 years old and 86.4% for those ages 65 and up. For both products, adverse events elevated in the vaccine arm of the trial included fatigue, fever, headache, myalgia, arthralgia, pain/swelling at the injection site, lymphadenopathy, nausea, erythema, Bell’s palsy and appendicitis.

    This triumph for RNA vaccine development has been three decades in the making. The first reports that foreign mRNA could express protein and induce cellular immunity when injected into mouse muscle came in the 1990s. Until the early noughts, however, progress was dogged by inflammatory reactions mediated by innate immune sensors for double-stranded (ds)RNA (for example, cytoplasmic protein kinase R (PKR) and 2′-5′-oligoadenylate synthetase, IFIT1, MDA5 and RIG-I) and for single-stranded RNA (for example, endosomal Toll-like receptor 3 (TLR3), TLR7 and TLR8). This reactogenicity, together with mRNA’s fragility (to RNases), large size (thousands of bases) and mediocre potency, led to widespread skepticism around the modality.

    A breakthrough came in 2005 when Katalin Karikó, Drew Weissman and their colleagues demonstrated that nucleoside modifications, such as pseudouridine and 5-methylcytidine, ablate TLR signaling (and later when they showed similar dampening of PKR activation). That modified RNA actually produces more protein than unmodified mRNA was a big surprise. Reactogenicity was addressed via codon optimization and removal of dsRNA contaminant from the in vitro transcription reaction by various purification methods.

    Immune reactivity was not the only problem, however. As with other nucleic acid modalities, mRNAs are large molecules to get into cells — either via ex vivo delivery to cells (for example, as in dendritic cell cancer vaccines) or direct parenteral injection with or without a carrier. Many carriers were tried, including protaminecationic liposomescationic nanoemulsionsdendrimerspolymers and LNPs. In 2012, Tekmira Pharmaceuticals’ ionizable LNPs, which galvanized Alnylam’s siRNA programs, began testing for mRNA; the same year, Novartis vaccines (now part of GlaxoSmithKline) showed that ionizable LNPs could potentiate a self-amplifying RNA vaccine. Today, ionizable LNPs are the carrier of choice.

    Over the years, mRNA stability and translation efficiency has also been tuned by optimizing regulatory elements in the 5′ and 3′ untranslated regions, poly(A) tail length and codon usage in the construct. Similarly, mRNA–LNP formulation is moving from macroscale mixing to more reproducible microfluidic mixing devices.

    Unlike DNA vaccines, mRNA vaccines do not have to cross the nuclear envelope, they pose no risk of genomic integration, and they work in both dividing and non-dividing cells. Unlike protein and peptide vaccines, they are not restricted by major histocompatibility complex haplotype. That said, they have burdensome cold-chain requirements and are currently the most expensive COVID-19 vaccines.

    What is perhaps most exciting is the potential for mRNA as a rapid and generic platform for any desired immunogen(s). As upstream computational design and downstream processing and manufacture are standardized, custom work will mostly involve optimizing specific mRNA constructs to express efficiently in cells of interest. For SARS-CoV-2, Moderna was able to create mRNA-1273 in just six weeks after disclosure of the draft viral genome — a record turnaround for a vaccine candidate. For future pandemics, vaccine templates could even be prepared in advance for more rapid deployment.

    By January 2022, we will know whether the promise is realized. By then, millions of people will have received these vaccines. Pooled data from VAERSSentinel and other initiatives will provide a clearer picture of rare serious adverse events associated with immunization, such as severe allergic reactions to PEG. And burning issues beyond safety — whether these products can be used in pregnant women or children (given multisystem inflammatory syndrome), whether they afford long-term protection and whether asymptomatic vaccinated individuals are capable of transmission — will be answered.

    For now, though, these vaccines represent a new hope: the beginning of the end for this pandemic — and the advent of a new era in vaccinology.

    https://www.nature.com/articles/s41587-020-00807-1

    Optimising the COVID-19 vaccination programme for maximum short-term impact

     Short statement from the Joint Committee on Vaccination and Immunisation (JCVI-UK.GOV)

    Summary 

    • There has been a rapid increase in COVID-19 cases in the UK in December 2020 

    • Two vaccines now have MHRA Regulation 174 authorisation (Pfizer-BioNTech and AstraZeneca) 

    • Rapid delivery of the vaccines is required to protect those most vulnerable 

    • Short term vaccine efficacy from the first dose of the Pfizer-BioNTech vaccine is calculated at around 90%, short term vaccine efficacy from the first dose of the AstraZeneca vaccine is calculated at around 70% (efficacy estimates are not directly comparable between the two vaccines)

     • Given the high level of protection afforded by the first dose, models suggest that initially vaccinating a greater number of people with a single dose will prevent more deaths and hospitalisations than vaccinating a smaller number of people with two doses

     • The second dose is still important to provide longer lasting protection and is expected to be as or more effective when delivered at an interval of 12 weeks from the first dose


    https://app.box.com/s/iddfb4ppwkmtjusir2tc/file/759357623956?sb=/details








    mRNA Vaccines to Prevent COVID-19 Disease and Reported Allergic Reactions

     

    DOI:https://doi.org/10.1016/j.jaip.2020.12.047

    PDF: https://www.jaci-inpractice.org/action/showPdf?pii=S2213-2198%2820%2931411-2

    Abstract

    The recent Food and Drug Administration (FDA) approval of two highly effective COVID-19 vaccines from Pfizer-BioNtech and Moderna has brought hope to millions of American in the midst of an ongoing global pandemic. The FDA Emergency Use Authorization guidance for both vaccines is to not administer the vaccine to individuals with known history of a severe allergic reaction (e.g., anaphylaxis) to any component of the COVID-19 vaccine. The Centers for Diseases Control and Prevention (CDC) advises that all patients should be observed for 15 minutes after COVID-19 vaccination and staff must be able to identify and manage anaphylaxis. Post-FDA approval, despite very strong safety signals in both phase 3 trials, reports of possible allergic reactions have raised public concern. To provide reassurance and support during widespread vaccination across America, allergists must offer clear guidance to patients based on the best information available, but also in accordance with the broader recommendations of our US regulatory agencies. This review summarizes vaccine allergy epidemiology and proposes risk stratification schema: (1) for individuals with different allergy histories to safely receive their first COVID-19 vaccine and (2) for individuals who develop a reaction to their first dose of COVID-19 vaccine.