scholarly journals Safety and Immunogenicity of the Respiratory Syncytial Virus Vaccine RSV/ΔNS2/Δ1313/I1314L in RSV-Seronegative Children

2019 ◽  
Vol 222 (1) ◽  
pp. 82-91 ◽  
Author(s):  
Ruth A Karron ◽  
Cindy Luongo ◽  
Jocelyn San Mateo ◽  
Kimberli Wanionek ◽  
Peter L Collins ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Rational Design ◽  
Controlled Trial ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Temperature Sensitive ◽  
Double Blind ◽  
Respiratory Tract Illness ◽  
Syncytial Virus ◽  
Respiratory Syncytial Virus Vaccine

Abstract Background Respiratory syncytial virus (RSV) is the leading global cause of severe pediatric acute respiratory tract illness, and a vaccine is needed. RSV/ΔNS2/Δ1313/I1314L contains 2 attenuating elements: (1) deletion of the interferon antagonist NS2 gene and (2) deletion of codon 1313 of the RSV polymerase gene and the stabilizing missense mutation I1314L. This live vaccine candidate was temperature-sensitive, genetically stable, replication restricted, and immunogenic in nonhuman primates. Methods A single intranasal dose of RSV/ΔNS2/Δ1313/I1314L was evaluated in a double-blind, placebo-controlled trial (vaccine-placebo ratio, 2:1) at 106 plaque-forming units (PFU) in 15 RSV-seropositive children and at 105 and 106 PFU in 21 and 30 RSV-seronegative children, respectively. Results In RSV-seronegative children, the 105 PFU dose was overattenuated, but the 106 PFU dose was well tolerated, infectious (RSV/ΔNS2/Δ1313/I1314L replication detected in 90% of vaccinees), and immunogenic (geometric mean serum RSV plaque-reduction neutralizing antibody titer, 1:64). After the RSV season, 9 of 20 vaccinees had increases in the RSV titer that were significantly greater than those in 8 of 10 placebo recipients (1:955 vs 1:69, respectively), indicating that the vaccine primed for anamnestic responses after natural RSV exposure. Conclusion Rational design yielded a genetically stable candidate RSV vaccine that is attenuated yet immunogenic in RSV-seronegative children, warranting further evaluation. Clinical Trials Registration NCT01893554.

scholarly journals Prevention of Respiratory Syncytial Virus Infection in Healthy Adults by a Single Immunization of Ad26.RSV.preF in a Human Challenge Study

2021 ◽  
Author(s):  
Jerald Sadoff ◽  
Els De Paepe ◽  
John DeVincenzo ◽  
Efi Gymnopoulou ◽  
Joris Menten ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Geometric Mean ◽  
Area Under The Curve ◽  
Neutralizing Antibody ◽  
Healthy Adults ◽  
Controlled Study ◽  
Double Blind ◽  
Post Immunization ◽  
Rsv Infection ◽  
Syncytial Virus

Abstract Background Respiratory syncytial virus (RSV) is a significant cause of severe lower respiratory tract disease in children and older adults, but has no approved vaccine. This study assessed the potential of Ad26.RSV.preF to protect against RSV infection and disease in an RSV human challenge model. Methods In this double-blind, placebo-controlled study, healthy adults aged 18–50 years were randomized 1:1 to receive 1x1011 vp Ad26.RSV.preF or placebo intramuscularly. Twenty-eight days post-immunization, volunteers were challenged intranasally with RSV-A (Memphis 37b). Assesments included viral load (VL), RSV infections, clinical symptom score (CSS), safety and immunogenicity. Results Post-challenge, VL, RSV infections and disease severity were lower in Ad26.RSV.preF (n=27) versus placebo (n=26) recipients: median VL-AUC (area under the curve) qRT-PCR: 0.0 versus 236.0 (P=.012; predefined primary endpoint); median VL-AUC quantitative culture: 0.0 versus 109; RSV infections 11 (40.7%) versus 17 (65.4%); median RSV AUC-CSS 35 versus 167, respectively. From baseline to 28 days post-immunization, geometric mean fold-increases in RSV A2 neutralizing antibody titers of 5.8 and 0.9 were observed in Ad26.RSV.preF and placebo, respectively. Ad26.RSV.preF was well tolerated. Conclusions Ad26.RSV.preF demonstrated protection from RSV infection through immunization in a human challenge model, and therefore could potentially protect against natural RSV infection and disease. Clinical Trials Registration NCT03334695

scholarly journals A Randomized, Placebo-Controlled, Respiratory Syncytial Virus Human Challenge Study of the Antiviral Efficacy, Safety, and Pharmacokinetics of RV521, an Inhibitor of the RSV-F Protein

2019 ◽  
Vol 64 (2) ◽  
Author(s):  
John DeVincenzo ◽  
Dereck Tait ◽  
John Efthimiou ◽  
Julie Mori ◽  
Young-In Kim ◽  
...  
Keyword(s):  
Viral Load ◽  
Respiratory Syncytial Virus ◽  
Adverse Events ◽  
Disease Severity ◽  
Controlled Trial ◽  
Primary Analysis ◽  
Double Blind ◽  
Challenge Virus ◽  
F Protein ◽  
Syncytial Virus

ABSTRACT Effective treatments for respiratory syncytial virus (RSV) infection are lacking. Here, we report a human proof-of-concept study for RV521, a small-molecule antiviral inhibitor of the RSV-F protein. In this randomized, double-blind, placebo-controlled trial, healthy adults were challenged with RSV-A Memphis-37b. After infection was confirmed (or 5 days after challenge virus inoculation), subjects received RV521 (350 mg or 200 mg) or placebo orally every 12 h for 5 days. The primary endpoint was area under the curve (AUC) for viral load, as assessed by reverse transcriptase quantitative PCR (RT-qPCR) of nasal wash samples. The primary efficacy analysis set included subjects successfully infected with RSV who received ≥1 dose of study drug. A total of 66 subjects were enrolled (n = 22 per group); 53 were included in the primary analysis set (RV521 350 mg: n = 16; 200 mg: n = 18; placebo: n = 19). The mean AUC of RT-qPCR-assessed RSV viral load (log10 PFU equivalents [PFUe]/ml · h) was significantly lower with RV521 350 mg (185.26; standard error [SE], 31.17; P = 0.002) and 200 mg (224.35; SE, 37.60; P = 0.007) versus placebo (501.39; SE, 86.57). Disease severity improved with RV521 350 mg and 200 mg versus placebo (P = 0.002 and P = 0.009, respectively, for AUC total symptom score [score × hours]). Daily nasal mucus weight was significantly reduced (P = 0.010 and P = 0.038 for RV521 350 mg and 200 mg, respectively, versus placebo). All treatment-emergent adverse events were grade 1 or 2. No subjects discontinued due to adverse events. There was no evidence of clinically significant viral resistance, and only three variants were detected. RV521 effectively reduced RSV viral load and disease severity in humans and was well tolerated. (This study has been registered at ClinicalTrials.gov under registration no. NCT03258502.)

scholarly journals 2855. Respiratory Syncytial Virus Neutralizing Antibodies in Cord Blood and Serum from Infants up to 2 Years of Age in a Multinational Prospective Study

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S74-S75
Author(s):  
Joseph B Domachowske ◽  
Veronique Bianco ◽  
Ana Ceballos ◽  
Luis Cousin ◽  
Ulises D’Andrea ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Cord Blood ◽  
Neutralizing Antibodies ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Neutralization Assay ◽  
Entire Cohort ◽  
Syncytial Virus ◽  
Tract Infections

Abstract Background Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract infections (LRTI) during infancy worldwide. High cord blood (CB) concentrations of anti-RSV neutralizing antibody (nAb) may attenuate, delay, or prevent infant infection. We report RSV A and B nAb concentrations in CB and serum from a birth cohort at different time points through 2 years of age. Methods Between 2013 and 2017, newborns from 8 countries were studied prospectively from birth to 2 years of age (NCT01995175). CB was collected at birth for the entire cohort. A subcohort of children was randomly assigned to have one blood sample collected again at either 2, 4, 6, 12, 18, or 24 months of age. Sera were analyzed for RSV A and B nAb concentrations by serum neutralization assay. Active surveillance was used to identify LRTIs during the 2-year follow-up as previously reported. Results In total, 2,401 newborns were enrolled and followed up. >99% of infants had detectable CB RSV A and B nAb. Geometric mean antibody titers (GMTs) varied by country, but were overall higher for RSV B than for RSV A (327 vs. 251; Figure 1). The lowest GMTs were seen from CB sera collected from South African newborns (197 RSV A, 255 RSV B); Canadian newborns had the highest RSV A GMT (383), while Hondurans had the highest RSV B GMT (460). 1380 infants provided follow-up serum nAb results as part of the subcohort (Figure 2). Dramatic waning of GMTs was evident, with a ~3-fold drop in GMTs at 2 months of age, and an additional ~2-fold drop between 2 and 4 months of age. At 6 and 12 months of age, 71% and 50% of infants had RSV A nAb and GMTs were at a nadir of 14. At 6, 12, and 18 months of age, RSV B nAb was detected in 98%, 69%, and 63% of infants, respectively. The RSV B nAb nadir GMT of 20 was observed at 12 months of age, while the 6- and 18-month RSV B nAb GMTs were 30 and 31, respectively. A total of 1,017 LRTIs were identified during the 2-year study period; of which, 94 (9%) were caused by RSV A and 132 (13%) by RSV B. Associations between CB nAb levels and RSV infection will be presented. Conclusion Neutralizing Ab to RSV A and B was present at birth in infants from 8 countries, and waned over time. GMTs were at a nadir at 6 to 12 months of age. Funding. GlaxoSmithKline Biologicals SA. Disclosures All Authors: No reported Disclosures.

scholarly journals Immunogenicity and Safety of 3 Formulations of a Respiratory Syncytial Virus Candidate Vaccine in Nonpregnant Women: A Phase 2, Randomized Trial

2019 ◽  
Vol 220 (11) ◽  
pp. 1816-1825 ◽  
Author(s):  
Tino F Schwarz ◽  
Roderick A McPhee ◽  
Odile Launay ◽  
Geert Leroux-Roels ◽  
Jaak Talli ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Neutralizing Antibodies ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Candidate Vaccine ◽  
Phase 2 ◽  
Serious Adverse Events ◽  
Intramuscular Dose ◽  
Syncytial Virus ◽  
Neonates And Infants

Abstract Background Respiratory syncytial virus (RSV) is a common cause of respiratory tract illness and hospitalization in neonates and infants. RSV vaccination during pregnancy may protect offspring in their first months of life. Methods This randomized, observer-blind, multicenter, phase 2 study evaluated the immunogenicity and safety of an RSV candidate vaccine in healthy nonpregnant women aged 18–45 years. Four hundred participants were randomized (1:1:1:1) to receive a single intramuscular dose of vaccine containing 30 µg, 60 µg, or 120 µg of RSV fusion protein engineered to preferentially maintain a prefusion conformation (RSV-PreF vaccine) or placebo. Results Thirty days postvaccination, RSV-A neutralizing antibody geometric mean titers (GMTs) increased 3.75-, 4.42- and 4.36-fold; RSV-B neutralizing antibody GMTs 2.36-, 2.54- and 2.76-fold; and palivizumab competing antibody (PCA) concentrations 11.69-, 14.38- and 14.24-fold compared with baseline levels in the 30 µg, 60 µg, and 120 µg RSV-PreF groups, respectively. Antibody titers and PCA concentrations at day 30 were significantly higher with the 120 µg compared to the 30 µg RSV-PreF vaccine. All RSV-PreF vaccine formulations and the placebo had similar reactogenicity profiles. No serious adverse events were considered to be related to the RSV-PreF vaccine. Conclusions The 3 formulations of the investigational RSV-PreF vaccine were well-tolerated and induced RSV-A and RSV-B neutralizing antibodies and PCAs in healthy, nonpregnant women. Clinical Trials Registration NCT02956837.

scholarly journals Three day versus five day treatment with amoxicillin for non-severe pneumonia in young children: a multicentre randomised controlled trial

BMJ ◽  
2004 ◽  
Vol 328 (7443) ◽  
pp. 791 ◽  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Confidence Interval ◽  
Respiratory Rate ◽  
Day Treatment ◽  
Controlled Trial ◽  
Severe Pneumonia ◽  
Absolute Difference ◽  
Double Blind ◽  
Oral Amoxicillin ◽  
Syncytial Virus

AbstractObjective To assess the efficacy of three days versus five days of treatment with oral amoxicillin for curing non-severe pneumonia in children.Design Randomised, double blind, placebo controlled multicentre trial.Setting Outpatient departments of seven referral hospitals in India.Participants 2188 children aged 2-59 months, 1095 given three days of treatment and 1093 given five days.Intervention Oral amoxicillin 31-54 mg/kg/day in three divided doses.Main outcome measures Treatment failure: defined as development of chest indrawing, convulsions, drowsiness, or inability to drink at any time; respiratory rate above age specific cut points on day 3 or later; or oxygen saturation by pulse oximetry < 90% on day 3.Results The clinical cure rates with three days and five days of treatment were 89.5% and 89.9%, respectively (absolute difference 0.4 (95% confidence interval - 2.1 to 3.0)). Adherence to treatment regimen was 94% and 85% for three day and five day treatments, respectively. Loss to follow up was 5.4% by day 5. There were no deaths, 41 hospitalisations, and 36 minor adverse reactions. There were 225 (10.3%) clinical failures and 106 (5.3%) relapses, and rates were similar in both treatments. At enrolment, 513 (23.4%) children tested positive for respiratory syncytial virus, and Streptococcus pneumoniae and Haemophilus influenzae were isolated from the nasopharynx in 878 (40.4%) and 496 (22.8%) children, respectively. Clinical failure was associated with isolation of respiratory syncytial virus (adjusted odds ratio 1.95 (95% confidence interval 1.0 to 3.8)), excess respiratory rate of > 10 breaths/minute (2.89 (1.83 to 4.55)), and non-adherence with treatment at day 5 (11.57 (7.4 to 18.0)).Conclusions Treatment with oral amoxicillin for three days was as effective as for five days in children with non-severe pneumonia.

scholarly journals A comparison of three vaccines against respiratory syncytial virus in calves

1984 ◽  
Vol 93 (2) ◽  
pp. 251-261 ◽  
Author(s):  
E. J. Stott ◽  
L. H. Thomas ◽  
G. Taylor ◽  
A. P. Collins ◽  
J. Jebbett ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Neutralizing Antibody ◽  
Temperature Sensitive ◽  
Virus Shedding ◽  
Live Vaccines ◽  
Bovine Strain ◽  
Nasal Swabs ◽  
Antibody Titres ◽  
The Mean ◽  
Syncytial Virus

SummaryAn inactivated vaccine against respiratory syncytial virus (RSV) was compared with two live vaccines. The inactivated (GC) vaccine consisted of glutaraldehyde-fixed bovine nasal mucosa cells persistently infected with RSV and emulsified with oil adjuvant. The live vaccines were a modified virus (MV) derived from a bovine strain of RSV and a temperature-sensitive mutant (ts-1) derived from a human strain. The GC vaccine was inoculated subcutaneously into 12 calves and the live vaccines intramuscularly into eight calves each. Nine unvaccinated calves acted as controls. The vaccines were administered in two doses 3 weeks apart and all calves were challenged intranasally with 2 × 107p.f.u. of bovine RSV 3 weeks after the second dose.At the time of challenge calves given GC, MV and ts-1 vaccines had mean serum neutralizing antibody titres of 25, 19 and 2 respectively; mean titres of IgG1antibody by radioimmunoassay were log104·5, 1·3 and 2·6 respectively and mean zone areas by single radial haemolysis (SRH) were 107, 27 and 36 mm2respectively.Eleven of 12 calves given GC vaccine were completely protected against challenge but all control animals and those given the two live vaccines were infected. The mean peak titre of virus in nasal swabs of control calves was 3.0 log10p.f.u./ml and the mean duration of virus shedding was 6·8 days. Both these parameters were significantly reduced in animals given MV and ts-1 vaccines: mean peak titres were 2·1 and 2·4 log10p.f.u./ml and mean duration of shedding was 3·4 and 3·3 days respectively.Thus, protection correlated better with RSV antibody detected by radio-immunoassay and SRH than with neutralizing antibody. These results are discussed in relation to the possible mechanism by which protection was mediated.

scholarly journals Evaluation of a Live, Cold‐Passaged, Temperature‐Sensitive, Respiratory Syncytial Virus Vaccine Candidate in Infancy

2000 ◽  
Vol 182 (5) ◽  
pp. 1331-1342 ◽  
Author(s):  
Peter F. Wright ◽  
Ruth A. Karron ◽  
Robert B. Belshe ◽  
Juliette Thompson ◽  
James E. Crowe, Jr. ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Virus Vaccine ◽  
Vaccine Candidate ◽  
Temperature Sensitive ◽  
Syncytial Virus ◽  
Respiratory Syncytial Virus Vaccine

scholarly journals Respiratory Syncytial Virus Vaccines

1998 ◽  
Vol 11 (3) ◽  
pp. 430-439 ◽  
Author(s):  
Robert A. Dudas ◽  
Ruth A. Karron
Keyword(s):  
Respiratory Syncytial Virus ◽  
The Elderly ◽  
Temperature Sensitive ◽  
Young Infants ◽  
Populations At Risk ◽  
History Of Disease ◽  
History Of ◽  
Respiratory Tract Illness ◽  
Syncytial Virus ◽  
Vector Delivery

SUMMARY Respiratory syncytial virus (RSV) is the most important cause of viral lower respiratory tract illness (LRI) in infants and children worldwide and causes significant LRI in the elderly and in immunocompromised patients. The goal of RSV vaccination is to prevent serious RSV-associated LRI. There are several obstacles to the development of successful RSV vaccines, including the need to immunize very young infants, who may respond inadequately to vaccination; the existence of two antigenically distinct RSV groups, A and B; and the history of disease enhancement following administration of a formalin-inactivated vaccine. It is likely that more than one type of vaccine will be needed to prevent RSV LRI in the various populations at risk. Although vector delivery systems, synthetic peptide, and immune-stimulating complex vaccines have been evaluated in animal models, only the purified F protein (PFP) subunit vaccines and live attenuated vaccines have been evaluated in recent clinical trials. PFP-2 appears to be a promising vaccine for the elderly and for RSV-seropositive children with underlying pulmonary disease, whereas live cold-passaged (cp), temperature-sensitive (ts) RSV vaccines (denoted cpts vaccines) would most probably be useful in young infants. The availability of cDNA technology should allow further refinement of existing live attenuated cpts candidate vaccines to produce engineered vaccines that are satisfactorily attenuated, immunogenic, and phenotypically stable.

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