Unique Features and Collateral Immune Effects of mRNA-LNP COVID-19 Vaccines: Plausible Mechanisms of Adverse Events and Complications

As COVID vaccines roll out, internists and other health care providers are being turned to as trusted sources of information for patients and communities. Here, experts from NIAID outline the current state of knowledge regarding such vaccines. They contrast vaccine platforms, summarize clinical trial data regarding efficacy and safety, and comment on key questions including the ability of current vaccines to protect against infection and to decrease the prevalence of virus in the community.

Role of the antigen presentation process in the immunization mechanism of the genetic vaccines against COVID-19 and the need for biodistribution evaluations.

Management of gastrointestinal adverse events induced by immune-checkpoint inhibitors

The ongoing COVID-19 pandemic inspired exceptional efforts in vaccine development. By January 10, exactly 12 months after the sequence of SARS-CoV-2 was reported, there were eight vaccines cleared for use. Michael Gross reports.

Immunization Update 2021

Vaccines based on mRNA technology have revolutionized the field. In fact, lipid nanoparticles (LNP) formulated with mRNA are the preferential vaccine platform used in the fight against SARS-CoV-2 infection, with wider application against other diseases. The high demand and property right protection of the most potent cationic/ionizable lipids used for LNP formulation of COVID-19 mRNA vaccines have promoted the design of alternative nanocarriers for nucleic acid delivery. In this study we have evaluated the immunogenicity and efficacy of different rationally designed lipid and polymeric-based nanoparticle prototypes against SARS-CoV-2 infection. An mRNA coding for a trimeric soluble form of the receptor binding domain (RBD) of the spike (S) protein from SARS-CoV-2 was encapsulated using different components to form nanoemulsions (NE), nanocapsules (NC) and lipid nanoparticles (LNP). The toxicity and biological activity of these prototypes were evaluated in cultured cells after transfection and in mice following homologous prime/boost immunization. Our findings reveal good levels of RBD protein expression with most of the formulations. In C57BL/6 mice immunized intramuscularly with two doses of formulated RBD-mRNA, the modified lipid nanoparticle (mLNP) and the classical lipid nanoparticle (LNP-1) were the most effective delivery nanocarriers at inducing binding and neutralizing antibodies against SARS-CoV-2. Both prototypes fully protected susceptible K18-hACE2 transgenic mice from morbidity and mortality following a SARS-CoV-2 challenge. These results highlight that modulation of mRNAs immunogenicity can be achieved by using alternative nanocarriers and support further assessment of mLNP and LNP-1 prototypes as delivery vehicles for mRNA vaccines.

Purpose: Cetuximab has been approved by FDA for the treatment of advanced/metastatic colorectal cancer. Whether cetuximab treatment is associated with an increase of severe adverse events in colorectal cancer (CRC) patients remains a question. The purpose is to assess the risk of severe adverse events of cetuximab treatment in advanced/metastatic CRC patients.Patients and methods: Search of EMBASE, PubMed, and ScienceDirect between 1 January, 2000 and 1 July 2012 for relevant randomized control trials (RCTs). Previous meta-analyses related with cetuximab treatment were also identified for eligible RCTs. Eligible studies were RCTs of advanced/metastatic CRC patients assigned to cetuximab or control group. Data were extracted by two authors for severe and fatal adverse events.Results: Nine RCTs, involving 8520 patients with CRC were included. Using a fixed-effects model, the proportion of patients with severe adverse events was higher in the cetuximab group than in control group with Mantel–Haenszel methods (OR, 2·19; 95% CI, 1·99–2·41; incidence, 70·0% versus 51·2%; P<0·001). The most common severe adverse events were neutropenia, diarrhea, and rash. However, cetuximab was not associated with increased risk of fatal adverse events (OR, 1·41; 95% CI, 0·99–2·03; incidence, 1·8% versus. 1·3%).Conclusion: In this meta-analysis of RCTs, cetuximab was associated with an increased risk of severe adverse events. There is no evidence of an increased risk of fatal adverse events with cetuximab.

Effect of rare variants in ADRB2 on risk of severe exacerbations and symptom control during longacting β agonist treatment in a multiethnic asthma population: a genetic study

Around 20%-30% of patients treated with fluoropyrimidines develop severe treatment-related adverse events (AEs). These are mainly caused by deficiency of dihydropyrimidine dehydrogenase, its main metabolizing enzyme. The DPYD*7 variant allele contains a frameshift mutation that leads to absence of dihydropyrimidine dehydrogenase. Clinical studies on this variant in patients treated with fluoropyrimidines are lacking because of its low minor allelic frequency. However, the DPYD*7 minor allelic frequency is 56-times higher in the Dutch compared with the global population. This allowed us to evaluate fluoropyrimidine tolerability in DPYD*7 variant allele carriers. Patients treated with standard-of-care fluoropyrimidine who were pretreatment DPYD genotyped for DPYD*2A, *13, 2846A>T, and 1236G>A single-nucleotide polymorphisms were included for analyses. Patients were additionally screened for the DPYD*7 allele (rs72549309, 295-298delTCAT). AEs were graded if they worsened from baseline, according to Common Terminology Criteria for Adverse Events version 5.0. AEs ≥ grade 3 were considered severe. From 3,748 patients, we found 13 patients carrying heterozygous DPYD*7. Relevant clinical data were available for 11 patients. All patients developed fluoropyrimidine-related AEs, of which five patients developed severe AEs (46%). From these five patients, three patients were started with 65% or 50% of standard dose, but apparently still developed severe toxicity. Because of severe AEs, three patients discontinued treatment prematurely (one patient already started with 50% of standard dose) and one patient who started with 50% of standard dose was further reduced to 35% of standard dose. In this study, the clinical consequences of carrying the DPYD*7 variant allele were confirmed as 46% of the patients developed severe AEs, even in the presence of initial dose reductions. This underlines the need for prospective studies investigating the required fluoropyrimidine dose for DPYD*7 carriers.

Self-amplifying mRNA (saRNA) is witnessing increased interest as a platform technology for protein replacement therapy, gene editing, immunotherapy, and vaccination. saRNA can replicate itself inside cells, leading to a higher and more sustained production of the desired protein at a lower dose. Controlling innate immune activation, however, is crucial to suppress unwanted inflammation upon delivery and self-replication of RNA in vivo. In this study, we report on a class of β-aminoester lipids (βAELs) synthesized through the Michael addition of an acrylate to diethanolamine, followed by esterification with fatty acids. These lipids possessed one or two ionizable amines, depending on the use of nonionic or amine-containing acrylates. We utilized βAELs for encapsulating saRNA in lipid nanoparticles (LNPs) and evaluated their transfection efficiency in vitro and in vivo in mice, while comparing them to LNPs containing ALC-0315 as an ionizable lipid reference. Among the tested lipids, OC7, which comprises two unsaturated oleoyl alkyl chains and an ionizable azepanyl motif, emerged as a βAEL with low cytotoxicity and immunogenicity relative to ALC-0315. Interestingly, saRNA delivered via the OC7 LNP exhibited a distinct in vivo transfection profile. Initially, intramuscular injection of OC7 LNP resulted in low protein expression shortly after administration, followed by a gradual increase over a period of up to 7 days. This pattern is indicative of successful self-amplification of saRNA. In contrast, saRNA delivered via ALC-0315 LNP demonstrated high protein translation initially, which gradually declined over time and lacked the amplification seen with OC7 LNP. We observed that, in contrast to saRNA OC7 LNP, saRNA ALC-0315 LNP induced potent innate immune activation by triggering cytoplasmic RIG-I-like receptors (RLRs), likely due to the highly efficient endosomal membrane rupturing properties of ALC-0315 LNP. Consequently, the massive production of type I interferons quickly hindered the amplification of the saRNA. Our findings highlight the critical role of the choice of ionizable lipid for saRNA formulation in LNPs, particularly in shaping the qualitative profile of protein expression. For applications where minimizing inflammation is desired, the use of ionizable lipids, such as the βAEL reported in this study, that elicit a low type I interferon response in saRNA LNP is crucial.

Coronavirus (SARS‐CoV‐2) as a global pandemic has attracted the attention of many scientific centers to find the right treatment. We expressed and purified the recombinant receptor‐binding domain (RBD) of the SARS‐CoV‐2 spike (S) protein, and specific RBD aptamers were designed using SELEX method. RNAi targeting nucleocapsid phosphoprotein was synthesized and human lung cells were inoculated with aptamer‐functionalized lipid nanoparticles (LNPs) containing RNAi. The results demonstrated that RBD aptamer having KD values of 0.290 nm possessed good affinity. Based on molecular docking and efficacy prediction analysis, siRNA molecule was showed the best action. LNPs were appropriately functionalized by aptamer and contained RNAi molecules. Antiviral assay using q‐PCR and ELISA demonstrated that LNP functionalized with 35 µm Apt and containing 30 nm RNAi/ml of cell culture had the best antiviral activity compared to other concentrations. Applied aptamer in the nanocarrier has two important functions. First, it can deliver the drug (RNAi) to the surface of epithelial cells. Second, by binding to the SARS‐CoV‐2 spike protein, it inhibits the virus entrance into cells. Our data reveal an interaction between the aptamer and the virus, and RNAi targeted the virus RNA. CT scan and the clinical laboratory tests in a clinical case study, a 36‐year old man who presented with severe SARS‐CoV‐2, demonstrated that inhalation of 10 mg Apt‐LNPs‐RNAi nebulized/day for six days resulted in an improvement in consolidation and ground‐glass opacity in lungs on the sixth day of treatment. Our findings suggest the treatment of SARS‐CoV‐2 infection through inhalation of Aptamer‐LNPs‐RNAi.

Mechanic Forces Promote Brain Endothelial Activation by SARS-CoV-2 Spike Protein.

To systematically analyze adverse events (AEs) in treatment of spinal muscular atrophy (SMA) with Nusinersen in children and adolescents. The study is registered on PROSPERO (CRD42022345589). Databases were searched and literature relating to Nusinersen in the treatment of spinal muscular atrophy in children from the start of database establishment to December 1, 2022, was retrospectively analyzed. R.3.6.3 statistical software was used, and random effects meta-analysis was performed to calculate weighted mean prevalence and 95% confidence intervals (CI). In total, 15 eligible studies were included, with a total of 967 children. Rate of definite Nusinersen-related AEs was 0.57% (95% CI: 0%-3.97%), and probable Nusinersen-related AEs 7.76% (95% CI: 1.85%-17.22%). Overall rate of AEs was 83.51% (95% CI: 73.55%-93.46%), and serious AEs 33.04% (95% CI: 18.15%-49.91%). For main specific AEs, fever was most common, 40.07% (95% CI: 25.14%-56.02%), followed by upper respiratory tract infection 39.94% (95% CI: 29.43%-50.94%), and pneumonia 26.62% (95% CI: 17.99%-36.25%).The difference in overall AE rates between the two groups (Nusinersen group and placebo group) was significant (OR = 0.27,95% CI: 0.08-0.95, P = 0.042). Moreover, incidence of serious adverse events, and fatal adverse events were both significantly lower than in the placebo group (OR = 0.47, 95%CI: 0.32-0.69, P < 0.01), and (OR = 0.37, 95%CI: 0.23-0.59, P < 0.01), respectively. Nusinersen direct adverse events are rare, and it can effectively reduces common, serious, and fatal adverse events in children and adolescents with spinal muscular atrophy.

Design and lyophilization of lipid nanoparticles for mRNA vaccine and its robust immune response in mice and nonhuman primates

BackgroundImmune checkpoint inhibitors such as nivolumab and targeted BRAF inhibitors have dramatically altered the treatment outcomes of metastatic melanoma over the past few years. Skin toxicity is the most common...