Anti-thrombotic treatment enhances antibiotic efficiency in a humanized model of meningococcemia

Meningococcal infections remain particularly difficult to treat. Despite antibiotic therapy, the state of the patients often rapidly deteriorates. Early clinical studies suggest that meningococci acquire a form of resistance to antibiotic treatments during infections. Taking advantage of a humanized animal model of infection, we confirm that adherent bacteria become highly resistant to antibiotic treatments as early as 3-6 hours post infection, although fully sensitive in vitro. Within this time frame, meningococci adhere to the endothelium via their type IV pili, proliferate and eventually fill the vessel lumen. Using intravital imaging, we show that rapidly upon infection blood flow is dramatically decreased, thus limiting antibiotic access to infected vessels. Concomitantly, fibrin is deposited inside infected vessels in proximity to bacterial aggregates. Pharmacologically impairing thrombin generation by inhibiting Factor X activity not only improves blood flow in infected vessels, but also enhances the efficacy of the antibiotic treatment. Our results indicate that the combined administration of anticoagulants together with antibiotics might represent a therapeutic approach to treat meningococcal sepsis more efficiently.

Two-Year Efficacy and Safety of Ravulizumab in Adults and Children with Atypical Hemolytic Uremic Syndrome (aHUS): Analysis of Two Phase 3 Studies

Background Ravulizumab, a humanized anti-complement C5 monoclonal antibody designed by targeted modification of eculizumab to achieve an extended half-life, is approved to treat aHUS in the USA (2019), EU and Japan (2020). Data at 26 weeks (wk) and 1 year (yr) from the phase 3 studies of ravulizumab in adults and children with aHUS have been published. Here we report 2-yr data from these trials. Methods Efficacy and safety data from ravulizumab clinical trials in adults naïve to complement inhibitor treatment (NCT02949128), and in children either naïve to (naïve) or switched from (switch) eculizumab (NCT03131219), were assessed at 2 yr and presented alongside data from the initial 26-wk evaluation periods; patients were dosed every 8 wk (adult), or every 4 or 8 wk (children), according to body weight. Descriptive statistical analyses were conducted on these data. No statistical comparisons between data at 26 wk and 2 yr, or between trials, were conducted. Results Efficacy data in adults and treatment-naïve children are presented in the Table. Complete thrombotic microangiopathy (TMA) response (platelet count normalization, lactate dehydrogenase normalization, and ≥25% improvement in serum creatinine from baseline, met concurrently at 2 separate assessments, at least 4 wk apart) was achieved in more patients at 2 yr vs 26 wk in both studies (adult: 34 [61%) vs 30 [54%]; naïve: 18 [90%] vs 15 [75%]). All complete TMA response components were either numerically improved or maintained at 2 yr vs 26 wk. Kidney function continued to improve, with the median change in estimated glomerular filtration rate from baseline numerically increasing at 2 yr vs 26 wk in both adults (35 vs 29 mL/min/1.73m 2) and naïve children (82.5 vs 80 mL/min/1.73m 2). Most patients receiving dialysis at baseline were able to discontinue dialysis at 26 wk; this was sustained in adults (67% vs 67%) while all naïve children receiving dialysis at baseline had discontinued by 2 yr (83% vs 100%). No patients who discontinued dialysis by 26 wk subsequently restarted. Chronic kidney disease (CKD) stage improved in most patients through 26 wk in both studies (adult, 68%; naïve, 88%); improvements were sustained at 2 yr (adult, 71%; naïve, 94%). No naïve children experienced a worsening of CKD stage at 2 yr. Improvements from baseline in quality of life were seen at both 26 wk and 2 yr, as measured by Functional Assessment of Chronic Illness Therapy-Fatigue (adults: 20 vs 12; naïve: 10 vs 8), EQ-5D-3L visual analog scale (adults: 32 vs 33) and EQ-5D-3L time trade-off (adults: 0.32 vs 0.31). Most adverse events (AEs) and serious AEs (SAEs) occurring in these studies were reported during the initial 26-wk evaluation period, with a general reduction in the number of patients with any new S/AE events being reported at 2 yr. The most common AEs reported through 2 yr, which had not met the 15% reporting threshold through 26 wk, were (n, %): adults - constipation (9, 16%), fatigue (9, 16%) and nasopharyngitis (9, 16%); naïve children - abdominal pain (6, 25%), contusion (5, 21%), cough (5, 21%), nausea (4, 17%), myalgia (4, 17%), rash (4, 17%) and rhinorrhea (4, 17%); switch children - upper respiratory tract infections (URTI; 4, 40%), oropharyngeal pain (3, 30%), pharyngitis (3, 30%), cough (2, 20%), gastroenteritis (2, 20%), nasopharyngitis (2, 20%), otitis media (2, 20%), viral URTI (2, 20%) and dehydration (2, 20%). No patients discontinued either study due to treatment-emergent AEs after 26 wk. No meningococcal infections were recorded in either study at any timepoints. One adult patient, who had previously met complete TMA response criteria while receiving therapy, discontinued treatment by choice and subsequently experienced recurrent disease, as evidenced by an increase in serum creatinine (SCr). This patient then restarted therapy, leading to improvements in SCr levels. Conclusions In both treatment-naïve adults and children, ravulizumab was associated with numerically sustained or increased improvements in hematologic outcomes and kidney function at 2 yr vs 26 wk. Fewer S/AEs were reported during the extension period of these studies vs the initial 26-wk evaluation periods. Importantly, no meningococcal infections were reported in either study at any timepoint. The data suggest that long-term treatment with ravulizumab is well tolerated and may be associated with continuing improvements in TMA parameters and renal function in adults and children with aHUS. Figure 1 Figure 1. Disclosures Dixon: Apellis Pharmaceuticals: Consultancy; Horizon Pharmaceuticals: Consultancy; Alexion Pharmaceuticals: Consultancy. Kavanagh: Gyroscope Therapeutics: Current equity holder in publicly-traded company, Honoraria, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties; Apellis: Honoraria, Speakers Bureau; Idorsia: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Alexion Pharmaceuticals: Honoraria, Speakers Bureau. Kang: Alexion Pharmaceuticals: Honoraria, Research Funding; Handok: Honoraria; Kyowa Kirin: Honoraria, Research Funding; Amgen: Research Funding; Bayer: Research Funding. Wang: Alexion, AstraZeneca Rare Disease Inc.: Current Employment. Garlo: Alexion: Current Employment; AstraZeneca: Current Employment. Greenbaum: Alexion Pharmaceuticals: Honoraria, Research Funding. Ogawa: Alexion Pharmaceuticals: Current Employment. Cataland: Ablynx/Sanofi: Consultancy, Research Funding; Sanofi Genzyme: Consultancy; Alexion: Consultancy, Research Funding; Takeda: Consultancy. Miyakawa: Sanofi: Consultancy; Zenyaku Kogyo: Consultancy; Sanofi: Research Funding; argenx: Consultancy, Research Funding.

The influence of the self-isolation regime on the prevalence of infectious diseases in children living in urban and rural areas

Relevance: Infectious diseases are one of the most pressing problems in pediatrics, in particular the COVID-19 pandemic has had a huge impact on society and health.Purpose of the work: to analyze the frequency of infectious diseases in children of the Udmurt Republic during a pandemic of a new coronavirus infection using the example of rural and urban areas.Materials and methods: a statistical analysis of the official medical documentation (form No. 12) of the Udmurt Republic «Mozhginskaya regional hospital of the Ministry of Health of the Udmurt Republic» and the Budgetary Establishment of Health of the Udmurt Republic Alnash District Hospital of the Ministry of Health of the Udmurt Republic for 2019—2020 for children with infectious diseases up to 14 years old inclusive was carried out.Result: the incidence of infectious diseases decreased: in Mozhga it decreased by one third (33%) compared to the previous year (13889 and 9318 cases); in Al-nash experienced a more significant reduction in 2 times (3618 and 1513 cases, respectively). The rate of decline in Mozhga was 33%. The maximum values are traced among the following nosologies: influenza, viral hepatitis, meningococcal infections (the rate of decline was 100%). In Alnash, the rate of decline was 58%, the highest rates were in laryngitis and tracheitis (the rate of decline was 73%). The downward trend in infectious pathology during a pandemic is similar in urban and rural areas.Conclusion: restrictive measures against COVID-19 contributed to a decrease in the incidence of infectious pathology, which is more transmitted by airborne droplets, but also spread by fecal-oral and contact-household routes. Studying the characteristics of the incidence of infectious diseases during the period of self-isolation can help doctors control the level of morbidity in the future.

Exploring the Ability of Meningococcal Vaccines to Elicit Mucosal Immunity: Insights from Humans and Mice

Neisseria meningitidis causes a devastating invasive disease but is also a normal colonizer of the human nasopharynx. Due to the rapid progression of disease, the best tool to protect individuals against meningococcal infections is immunization. Clinical experience with polysaccharide conjugate vaccines has revealed that an ideal meningococcal vaccine must prevent both invasive disease and nasal colonization, which confers herd immunity. However, not all meningococcal vaccines are equal in their ability to prevent nasal colonization, for unknown reasons. Herein, we describe recent efforts to utilize humanized mouse models to understand the impact of different meningococcal vaccines on nasal colonization. These mice are susceptible to nasal colonization, and they become immune following live nasal infection or immunization with matched capsule-conjugate or protein-based vaccines, replicating findings from human work. We bring together insights regarding meningococcal colonization and immunity from clinical work with findings using humanized mouse models, providing new perspective into the different determinants of mucosal versus systemic immunity. Then, we use this as a framework to help focus future studies toward understanding key mechanistic aspects left unresolved, including the bacterial factors required for colonization and immune evasion, determinants of nasal mucosal protection, and characteristics of an ideal meningococcal vaccine.

Extended Spectrum Beta Lactamase (ESBL) Producing Neisseria meningitidis – Isolated from a Case of Pneumonia

Neisseria meningitidis (meningococci) is the most common cause of bacterial meningitis in all age groups. Invasive meningococcal disease manifesting as meningococcal pneumonia is a very rare clinical condition. Here we have a 72 year old male who presented with meningococcal pneumonia and sepsis following a flu like illness. It is notable that he did not develop the syndrome of meningococcemia or its associated complications. This patient was treated with injections of Piperacillin-Tazobactum and Azithromycin because of the unusual antibiotic resistance pattern of the organism. He recovered completely without any sequelae. The meningococci isolated was an ESBL (extended spectrum beta lactamase) producing strain, hence it was resistant to Penicillin and third generation Cephalosporins which are usually used for the treatment of meningococcal infections .This strain was also resistant to Ciprofloxacin .This poses a threat to the community as well, especially because Ciprofloxacin is used as a chemo prophylactic drug by the contacts of the patient and the laboratory workers dealing with the patient’s clinical samples.

Carbohydrate based meningococcal vaccines: past and present overview

Neisseria meningitidis is a major cause of bacterial meningitidis worldwide. Children less than five years and adolescents are particularly affected. Nearly all invasive strains are surrounded by a polysaccharide capsule, based on which, 12 N. meningitidis serogroups are differentiated. Six of them, A, B, C, W, X, and Y, cause the vast majority of infections in humans. Mono- and multi-valent carbohydrate-based vaccines against meningococcal infections have been licensed or are currently in clinical development. In this mini-review, an overview of the past and present approaches for producing meningococcal glycoconjugate vaccines is provided.

Efficacy and safety of the long-acting C5 inhibitor ravulizumab in patients with atypical hemolytic uremic syndrome triggered by pregnancy: a subgroup analysis

Background Atypical hemolytic uremic syndrome (aHUS) triggered by pregnancy is a rare disease caused by dysregulation of the alternative complement pathway that occurs in approximately 1 in 25,000 pregnancies. The 311 phase 3 trial (NCT02949128) showed that ravulizumab, a long-acting C5 inhibitor obtained through selective modifications to eculizumab, is efficacious in inhibiting complement-mediated thrombotic microangiopathy (TMA) in patients with aHUS. In this analysis, we report outcomes in a subgroup of patients from the 311 study who developed TMA postpartum. Methods This was a phase 3, multicenter trial evaluating efficacy and safety of ravulizumab in adults (≥18 years of age) with aHUS naïve to complement inhibitor treatment. The primary endpoint was complete TMA response (simultaneous platelet count normalization [≥150 × 109/L], lactate dehydrogenase normalization [≤246 U/L] and 25% improvement in serum creatinine) through the 183-day initial evaluation period. Additional efficacy endpoints included time to complete TMA response, hematologic normalization, and dialysis requirement status. Results Eight patients presenting with TMA postpartum (median age of 37.7 [range; 22.1–45.2] years) were diagnosed with aHUS and received ≥1 dose of ravulizumab. Five patients (63%) were on dialysis at baseline. Complete TMA response was achieved in 7/8 patients (87.5%) in a median time of 31.5 days. Hematologic normalization was observed in all patients. All patients on dialysis at baseline discontinued dialysis within 21 days after treatment with ravulizumab. All patients showed continued improvements in the estimated glomerular filtration rate from baseline to Day 183. Three possible treatment-related adverse events were observed in 2 patients (arthralgia and nasopharyngitis [both non-severe]; urinary tract infection). No deaths or meningococcal infections occurred. Conclusions Treatment with ravulizumab provided immediate and complete C5 inhibition, resulting in rapid clinical and laboratory improvements and complete TMA response through 183 days in patients with aHUS triggered by pregnancy. The safety profile observed in this subset of patients analysed is consistent with the 311 study investigating ravulizumab in patients with aHUS naïve to complement treatment. Trial registration Clinical trial identifier:NCT02949128.

Efficacy and safety of the long-acting C5 inhibitor ravulizumab in patients with atypical hemolytic uremic syndrome triggered by pregnancy: a subgroup analysis

Background: Atypical hemolytic uremic syndrome (aHUS) triggered by pregnancy is a rare disease caused by dysregulation of the alternative complement pathway that occurs in approximately 1 in 25,000 pregnancies. The 311 phase 3 trial (NCT02949128) showed that ravulizumab, a long-acting C5 inhibitor obtained through selective modifications to eculizumab, is efficacious in inhibiting complement-mediated thrombotic microangiopathy (TMA) in patients with aHUS. In this analysis, we report outcomes in a subgroup of patients from the 311 study who developed TMA postpartum. Methods: This was a phase 3, multicenter trial evaluating efficacy and safety of ravulizumab in adults (≥18 years of age) with aHUS naïve to complement inhibitor treatment. The primary endpoint was complete TMA response (simultaneous platelet count normalization [≥150 x 109/L], lactate dehydrogenase normalization [≤246 U/L] and 25% improvement in serum creatinine) through the 183-day initial evaluation period. Additional efficacy endpoints included time to complete TMA response, hematologic normalization, and dialysis requirement status. Results: Eight patients presenting with TMA postpartum (median age of 37.7 [range; 22.1–45.2] years) were diagnosed with aHUS and received ≥1 dose of ravulizumab. Five patients (63%) were on dialysis at baseline. Complete TMA response was achieved in 7/8 patients (87.5%) in a median time of 31.5 days. Hematologic normalization was observed in all patients. All patients on dialysis at baseline discontinued dialysis within 21 days after treatment with ravulizumab. All patients showed continued improvements in the estimated glomerular filtration rate from baseline to Day 183. Three possible treatment-related adverse events were observed in 2 patients (arthralgia and nasopharyngitis [both non-severe]; urinary tract infection). No deaths or meningococcal infections occurred.Conclusions: Treatment with ravulizumab provided immediate and complete C5 inhibition, resulting in rapid clinical and laboratory improvements and complete TMA response through 183 days in patients with aHUS triggered by pregnancy. The safety profile observed in this subset of patients analysed is consistent with the 311 study investigating ravulizumab in patients with aHUS naïve to complement treatment.

Rituximab and eculizumab when treating nonmalignant hematologic disorders: infection risk, immunization recommendations, and antimicrobial prophylaxis needs

Rituximab and eculizumab, monoclonal antibodies that deplete most B cells and activate the terminal complement, respectively, are used to treat nonmalignant hematologic disorders (NMHDs), sometimes with unfavorable effects on the immune system. Hypogammaglobulinemia and neutropenia have been reported with variable prevalence in patients treated with rituximab. Neutropenia is mild and transient, and serious infectious complications are uncommon, so treatment is not indicated. Hypogammaglobulinemia is of greater concern. There is a lack of agreement on a standardized definition, and pre- and posttreatment immunoglobulin (Ig) levels are not routinely obtained. The association among low Ig levels, infectious risk, and mortality and morbidity in this population is unclear. There are also no formal guidelines on indication, risk factors, and threshold level of IgG to prompt Ig replacement therapy (IgRT). Among patients with NMHD, preexisting or persistent hypogammaglobulinemia (PH) after treatment with rituximab has been linked to underlying primary immunodeficiency disorders; therefore, a high index of suspicion should be maintained, and immunologic and genetic evaluation should be considered. Overall, important strategies in managing patients who are receiving rituximab include routine monitoring of pre- and posttreatment IgG levels, immune reconstitution (eg, B-cell subsets), assessment of vaccination status and optimization before treatment, and individualized consideration for IgRT. Accordingly, we discuss immunizations. Eculizumab, most commonly used in the treatment of paroxysmal nocturnal hemoglobinuria and atypical hemolytic uremic syndrome, poses increased risk of meningococcal infections. To decrease the risk of infection, a meningococcal vaccination series is recommended before initiating therapy, and prophylactic antibiotics are preferred during the course of treatment.