Journal: eClinicalMedicine

Article Title: Safety and immunogenicity of bivalent RSVpreF vaccine formulated in a multidose vial in healthy female participants in the USA: a multicentre, randomised, open-label, noninferiority phase 3 study

doi: 10.1016/j.eclinm.2026.103767

Figure Lengend Snippet: Participant dispositions and analysis populations . a One participant did not complete the 1-month postvaccination visit but completed the end-of-study telephone call. b The end-of-study telephone call was scheduled to take place 42–49 days after vaccination. c Participants could be excluded for more than one reason. MDV = multidose vial; RSVpreF = respiratory syncytial virus prefusion F protein vaccine; SDV = single-dose vial.

Article Snippet: Multiple phase 3 clinical trials have demonstrated safety, immunogenicity, and efficacy of the bivalent RSV prefusion F protein unadjuvanted vaccine (RSVpreF; Abrysvo®; Pfizer Inc, New York, NY, USA), leading to US approval in 2023. , , , , In the placebo-controlled phase 3 Maternal Immunization Study for Safety and Efficacy (MATISSE), efficacy rates of RSVpreF vaccination against severe RSV-associated medically attended lower respiratory tract illness among infants born to pregnant women who received 120 μg RSVpreF at 24–36 weeks’ gestation were 82·4% and 70·0% within 90 and 180 days after birth, respectively.

Techniques: Virus

Journal: eClinicalMedicine

Article Title: Safety and immunogenicity of bivalent RSVpreF vaccine formulated in a multidose vial in healthy female participants in the USA: a multicentre, randomised, open-label, noninferiority phase 3 study

doi: 10.1016/j.eclinm.2026.103767

Figure Lengend Snippet: (a) RSV neutralising GMRs of the RSVpreF MDV group to the RSVpreF SDV group at 1 month after vaccination and corresponding GMTs and GMFRs from baseline for (b) RSV A and (c) RSV B . Data are for the evaluable immunogenicity population. Error bars represent 95% CIs. Dotted line indicates prespecified noninferiority acceptance criteria for the lower limit of the 95% CIs. If the titre before vaccination was

Article Snippet: Multiple phase 3 clinical trials have demonstrated safety, immunogenicity, and efficacy of the bivalent RSV prefusion F protein unadjuvanted vaccine (RSVpreF; Abrysvo®; Pfizer Inc, New York, NY, USA), leading to US approval in 2023. , , , , In the placebo-controlled phase 3 Maternal Immunization Study for Safety and Efficacy (MATISSE), efficacy rates of RSVpreF vaccination against severe RSV-associated medically attended lower respiratory tract illness among infants born to pregnant women who received 120 μg RSVpreF at 24–36 weeks’ gestation were 82·4% and 70·0% within 90 and 180 days after birth, respectively.

Techniques: Immunopeptidomics, Transformation Assay, Quantitation Assay, Virus

Journal: eClinicalMedicine

Article Title: Safety and immunogenicity of bivalent RSVpreF vaccine formulated in a multidose vial in healthy female participants in the USA: a multicentre, randomised, open-label, noninferiority phase 3 study

doi: 10.1016/j.eclinm.2026.103767

Figure Lengend Snippet: Rates of (a) local reactions and (b) systemic events reported within 7 days after vaccination . Data are for the safety population. Error bars represent 95% CIs, which were calculated using the Clopper-Pearson method. The number of participants included in each group was as follows: RSVpreF MDV, n = 223; RSVpreF SDV, n = 227. Grading scales are provided in . MDV = multidose vial; RSVpreF = respiratory syncytial virus prefusion F protein vaccine; SDV = single-dose vial.

Article Snippet: Multiple phase 3 clinical trials have demonstrated safety, immunogenicity, and efficacy of the bivalent RSV prefusion F protein unadjuvanted vaccine (RSVpreF; Abrysvo®; Pfizer Inc, New York, NY, USA), leading to US approval in 2023. , , , , In the placebo-controlled phase 3 Maternal Immunization Study for Safety and Efficacy (MATISSE), efficacy rates of RSVpreF vaccination against severe RSV-associated medically attended lower respiratory tract illness among infants born to pregnant women who received 120 μg RSVpreF at 24–36 weeks’ gestation were 82·4% and 70·0% within 90 and 180 days after birth, respectively.

Techniques: Virus

Journal: PLoS ONE

Article Title: Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein

doi: 10.1371/journal.pone.0156798

Figure Lengend Snippet: Heavy chain C-terminal 6xHis tagged antigen specific bivalent Fabs were purified with Ni-NTA column and then tested in ELISA binding to RSV prefusion and postfusion F proteins. (A) Antibodies preferentially binding to RSV postfusion F protein; (B) Antibodies binding to both RSV postfusion and prefusion F proteins; (C) antibody binding specifically to RSV prefusion F protein. Full-length human IgG1 D25 (prefusion F specific) and palivizumab (binding to both prefusion and postfusion F) were used as control antibodies in the above experiments.

Article Snippet: Three groups of RSV F protein specific antibodies were identified from the Morphosys HuCAL GOLD ® phage display library ( ): group 1 mAbs (3B1, 3B5, 3E2, 3H3, 3G4) which bind to the postfusion RSV F protein strongly with minimal binding to the prefusion F protein ( ); group 2 mAbs (3B2, 3D3, 3B7 and 3C2) which bind to both prefusion and postfusion F proteins ( ); and group 3 mAb (2E1) which binds specifically to prefusion F protein, although weakly as a bivalent Fab ( ).

Techniques: Purification, Enzyme-linked Immunosorbent Assay, Binding Assay

Journal: PLoS ONE

Article Title: Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein

doi: 10.1371/journal.pone.0156798

Figure Lengend Snippet: (A-B) ELISA analysis of 2E1 IgG (A) and 3B1 IgG (B) binding to RSV pre- (red circle) and postfusion F (blue square) proteins. (C-H) Surface plasmon resonance (SPR) analysis of 2E1 and 3B1 Fabs binding to pre- and postfusion RSV F proteins. RU = Resonance Units. Monovalent Fab antibody fragments were captured on the surface of a Series S Sensor Chip CM5 previously functionalized with Human Fab Binder. Prefusion or postfusion F protein diluted 2-fold serially starting at 100 nM or 200 nM was then injected over captured 2E1 (C) or 3B1 (F), respectively. To determine steady-state affinity, response levels at equilibrium were plotted over concentration of pre- (D) or postfusion F (G) protein. 50 nM of post- (E) or prefusion F (H) was injected to demonstrate the specificity of 2E1 binding to prefusion F and 3B1 to postfusion F. (I-K) SPR based competition analysis of 2E1 and 3B1 against palivizumab (I), D25 (J) and MPE8 (K) in binding to RSV prefusion F protein. RU = Resonance Units. Palivizumab and D25 were amine coupled to the surface of separate flow channels of a CM5 chip. A third flow channel was subjected to amine coupling activation without an antibody and used for reference subtraction. Prefusion F (40 μg/mL) was then injected over all surfaces. After a brief stabilization period, 2E1, 3B1, or running buffer was injected to measure binding to sites not occupied by the capturing antibody (palivizumab or D25). To assess competition to MPE8, the MPE8 antibody was captured (6000 RU, not shown) to flow channel 2 of a Biacore Sensor Chip Protein A. Prefusion F (40 μg/mL) was passed over channels 1 and 2 followed by 2E1 Fab, 3B1 Fab, D25 Fab and buffer to measure binding to sites not occupied by MPE8. (L) Bio-Layer Interferometry (BLI) based competition experiment of 3B1 IgG against site I antibody 131-2a. Palivizumab (blue) is able to bind to postfusion F protein in an Octet sandwich competition assay using 131-2a as the capture antibody, but antibody 3B1 (red) does not bind.

Article Snippet: Three groups of RSV F protein specific antibodies were identified from the Morphosys HuCAL GOLD ® phage display library ( ): group 1 mAbs (3B1, 3B5, 3E2, 3H3, 3G4) which bind to the postfusion RSV F protein strongly with minimal binding to the prefusion F protein ( ); group 2 mAbs (3B2, 3D3, 3B7 and 3C2) which bind to both prefusion and postfusion F proteins ( ); and group 3 mAb (2E1) which binds specifically to prefusion F protein, although weakly as a bivalent Fab ( ).

Techniques: Enzyme-linked Immunosorbent Assay, Binding Assay, SPR Assay, Injection, Concentration Assay, Activation Assay, Competitive Binding Assay

Journal: PLoS ONE

Article Title: Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein

doi: 10.1371/journal.pone.0156798

Figure Lengend Snippet: (A) Heat map plot showing the difference in deuteration levels of the RSV prefusion F protein alone compared to RSV prefusion F protein in the presence of the 2E1 monovalent Fab at five time points (15, 50, 150, 500, and 1500 sec). Slower deuterium exchange indicates regions containing the binding sites. White areas are ‘gaps’ for which there was no sequence coverage, and thus no HDX-MS information was obtained. Dashed greyed-out areas represent sequences of the signal and P27 peptides which are not present in the mature purified protein. (B) Uptake plots of several RSV F peptides spanning the conformational epitope region. Red curves show the deuteration levels of peptides of RSV F protein alone, while blue curves show the peptides of the RSV F / 2E1 complex. Peptides containing the residues of antibody epitope (417–434, 441–448, and 457–467) showed decreased deuteration level upon 2E1 binding. In contrast, peptides with no significant decrease in the deuteration level upon 2E1 exposure represent non-epitope sequences (435–440 and 449–457). The residues identified as critical for binding by shotgun mutagenesis are indicated in red font.

Article Snippet: Three groups of RSV F protein specific antibodies were identified from the Morphosys HuCAL GOLD ® phage display library ( ): group 1 mAbs (3B1, 3B5, 3E2, 3H3, 3G4) which bind to the postfusion RSV F protein strongly with minimal binding to the prefusion F protein ( ); group 2 mAbs (3B2, 3D3, 3B7 and 3C2) which bind to both prefusion and postfusion F proteins ( ); and group 3 mAb (2E1) which binds specifically to prefusion F protein, although weakly as a bivalent Fab ( ).

Techniques: Binding Assay, Sequencing, Purification, Mutagenesis

Journal: PLoS ONE

Article Title: Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein

doi: 10.1371/journal.pone.0156798

Figure Lengend Snippet: Heavy chain C-terminal 6xHis tagged antigen specific bivalent Fabs were purified with Ni-NTA column and then tested in ELISA binding to RSV prefusion and postfusion F proteins. (A) Antibodies preferentially binding to RSV postfusion F protein; (B) Antibodies binding to both RSV postfusion and prefusion F proteins; (C) antibody binding specifically to RSV prefusion F protein. Full-length human IgG1 D25 (prefusion F specific) and palivizumab (binding to both prefusion and postfusion F) were used as control antibodies in the above experiments.

Article Snippet: Three groups of RSV F protein specific antibodies were identified from the Morphosys HuCAL GOLD ® phage display library ( ): group 1 mAbs (3B1, 3B5, 3E2, 3H3, 3G4) which bind to the postfusion RSV F protein strongly with minimal binding to the prefusion F protein ( ); group 2 mAbs (3B2, 3D3, 3B7 and 3C2) which bind to both prefusion and postfusion F proteins ( ); and group 3 mAb (2E1) which binds specifically to prefusion F protein, although weakly as a bivalent Fab ( ).

Techniques: Purification, Enzyme-linked Immunosorbent Assay, Binding Assay

Journal: PLoS ONE

Article Title: Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein

doi: 10.1371/journal.pone.0156798

Figure Lengend Snippet: (A-B) ELISA analysis of 2E1 IgG (A) and 3B1 IgG (B) binding to RSV pre- (red circle) and postfusion F (blue square) proteins. (C-H) Surface plasmon resonance (SPR) analysis of 2E1 and 3B1 Fabs binding to pre- and postfusion RSV F proteins. RU = Resonance Units. Monovalent Fab antibody fragments were captured on the surface of a Series S Sensor Chip CM5 previously functionalized with Human Fab Binder. Prefusion or postfusion F protein diluted 2-fold serially starting at 100 nM or 200 nM was then injected over captured 2E1 (C) or 3B1 (F), respectively. To determine steady-state affinity, response levels at equilibrium were plotted over concentration of pre- (D) or postfusion F (G) protein. 50 nM of post- (E) or prefusion F (H) was injected to demonstrate the specificity of 2E1 binding to prefusion F and 3B1 to postfusion F. (I-K) SPR based competition analysis of 2E1 and 3B1 against palivizumab (I), D25 (J) and MPE8 (K) in binding to RSV prefusion F protein. RU = Resonance Units. Palivizumab and D25 were amine coupled to the surface of separate flow channels of a CM5 chip. A third flow channel was subjected to amine coupling activation without an antibody and used for reference subtraction. Prefusion F (40 μg/mL) was then injected over all surfaces. After a brief stabilization period, 2E1, 3B1, or running buffer was injected to measure binding to sites not occupied by the capturing antibody (palivizumab or D25). To assess competition to MPE8, the MPE8 antibody was captured (6000 RU, not shown) to flow channel 2 of a Biacore Sensor Chip Protein A. Prefusion F (40 μg/mL) was passed over channels 1 and 2 followed by 2E1 Fab, 3B1 Fab, D25 Fab and buffer to measure binding to sites not occupied by MPE8. (L) Bio-Layer Interferometry (BLI) based competition experiment of 3B1 IgG against site I antibody 131-2a. Palivizumab (blue) is able to bind to postfusion F protein in an Octet sandwich competition assay using 131-2a as the capture antibody, but antibody 3B1 (red) does not bind.

Article Snippet: Three groups of RSV F protein specific antibodies were identified from the Morphosys HuCAL GOLD ® phage display library ( ): group 1 mAbs (3B1, 3B5, 3E2, 3H3, 3G4) which bind to the postfusion RSV F protein strongly with minimal binding to the prefusion F protein ( ); group 2 mAbs (3B2, 3D3, 3B7 and 3C2) which bind to both prefusion and postfusion F proteins ( ); and group 3 mAb (2E1) which binds specifically to prefusion F protein, although weakly as a bivalent Fab ( ).

Techniques: Enzyme-linked Immunosorbent Assay, Binding Assay, SPR Assay, Injection, Concentration Assay, Activation Assay, Competitive Binding Assay

Journal: PLoS ONE

Article Title: Discovery and Characterization of Phage Display-Derived Human Monoclonal Antibodies against RSV F Glycoprotein

doi: 10.1371/journal.pone.0156798

Figure Lengend Snippet: (A) Heat map plot showing the difference in deuteration levels of the RSV prefusion F protein alone compared to RSV prefusion F protein in the presence of the 2E1 monovalent Fab at five time points (15, 50, 150, 500, and 1500 sec). Slower deuterium exchange indicates regions containing the binding sites. White areas are ‘gaps’ for which there was no sequence coverage, and thus no HDX-MS information was obtained. Dashed greyed-out areas represent sequences of the signal and P27 peptides which are not present in the mature purified protein. (B) Uptake plots of several RSV F peptides spanning the conformational epitope region. Red curves show the deuteration levels of peptides of RSV F protein alone, while blue curves show the peptides of the RSV F / 2E1 complex. Peptides containing the residues of antibody epitope (417–434, 441–448, and 457–467) showed decreased deuteration level upon 2E1 binding. In contrast, peptides with no significant decrease in the deuteration level upon 2E1 exposure represent non-epitope sequences (435–440 and 449–457). The residues identified as critical for binding by shotgun mutagenesis are indicated in red font.

Article Snippet: Three groups of RSV F protein specific antibodies were identified from the Morphosys HuCAL GOLD ® phage display library ( ): group 1 mAbs (3B1, 3B5, 3E2, 3H3, 3G4) which bind to the postfusion RSV F protein strongly with minimal binding to the prefusion F protein ( ); group 2 mAbs (3B2, 3D3, 3B7 and 3C2) which bind to both prefusion and postfusion F proteins ( ); and group 3 mAb (2E1) which binds specifically to prefusion F protein, although weakly as a bivalent Fab ( ).

Techniques: Binding Assay, Sequencing, Purification, Mutagenesis

Journal: Obstetrics and Gynecology

Article Title: Preterm Birth Frequency and Associated Outcomes From the MATISSE (Maternal Immunization Study for Safety and Efficacy) Maternal Trial of the Bivalent Respiratory Syncytial Virus Prefusion F Protein Vaccine

doi: 10.1097/AOG.0000000000005817

Figure Lengend Snippet: Cumulative distribution, case counts, and cumulative case counts of gestational age at birth among newborns and infants born at less than 37 weeks of gestation. RSVpreF, respiratory syncytial virus prefusion F protein–based vaccine.

Article Snippet: To describe preterm birth frequency and newborn and infant outcomes overall and among preterm children in the MATISSE (Maternal Immunization Study for Safety and Efficacy) trial of maternal vaccination with bivalent respiratory syncytial virus (RSV) prefusion F protein–based vaccine (RSVpreF) to protect infants against severe RSV-associated illness.

Techniques: Virus

Journal: Obstetrics and Gynecology

Article Title: Preterm Birth Frequency and Associated Outcomes From the MATISSE (Maternal Immunization Study for Safety and Efficacy) Maternal Trial of the Bivalent Respiratory Syncytial Virus Prefusion F Protein Vaccine

doi: 10.1097/AOG.0000000000005817

Figure Lengend Snippet: Relative risk for newborn and infant outcomes ( A ) and newborn and infant deaths during the study ( B ). Shown are data from the newborn and infant safety population. Serious adverse event (SAE)–related hospitalizations were within the neonatal period (ie, 4 weeks). Low Apgar scores were a first score lower than 4 or last score lower than 7. AE, adverse event; RSVpreF, respiratory syncytial virus prefusion F protein–based vaccine.

Article Snippet: To describe preterm birth frequency and newborn and infant outcomes overall and among preterm children in the MATISSE (Maternal Immunization Study for Safety and Efficacy) trial of maternal vaccination with bivalent respiratory syncytial virus (RSV) prefusion F protein–based vaccine (RSVpreF) to protect infants against severe RSV-associated illness.

Techniques: Virus

Journal: Obstetrics and Gynecology

Article Title: Preterm Birth Frequency and Associated Outcomes From the MATISSE (Maternal Immunization Study for Safety and Efficacy) Maternal Trial of the Bivalent Respiratory Syncytial Virus Prefusion F Protein Vaccine

doi: 10.1097/AOG.0000000000005817

Figure Lengend Snippet: Preterm births by gestational age (GA) at vaccination. Shown are data from the infant safety population. Numbers above the error bars are the preterm birth rate (less than 37 weeks of gestation) overall and by GA at vaccination. Also shown is the relative risk (95% CI). In the overall and less than 28 weeks of gestation at vaccination groups, the rate of GA at birth of 24–less than 28 weeks was less than 0.1% (n=1) in both the respiratory syncytial virus prefusion F protein–based vaccine (RSVpreF) and placebo groups.

Article Snippet: To describe preterm birth frequency and newborn and infant outcomes overall and among preterm children in the MATISSE (Maternal Immunization Study for Safety and Efficacy) trial of maternal vaccination with bivalent respiratory syncytial virus (RSV) prefusion F protein–based vaccine (RSVpreF) to protect infants against severe RSV-associated illness.

Techniques: Virus

Journal: Obstetrics and Gynecology

Article Title: Preterm Birth Frequency and Associated Outcomes From the MATISSE (Maternal Immunization Study for Safety and Efficacy) Maternal Trial of the Bivalent Respiratory Syncytial Virus Prefusion F Protein Vaccine

doi: 10.1097/AOG.0000000000005817

Figure Lengend Snippet: Preterm births by income region ( A ) and relative risk for preterm birth overall and by country ( B ). Shown are data from the newborn and infant safety population. A. Numbers above the bars are the preterm birth rate (less than 37 weeks of gestational age [GA]) overall and by World Bank income region. Also shown is the relative risk (95% CI). In the overall group, the rate of GA at birth of 24–less than 28 weeks was less than 0.1% (n=1) in both the respiratory syncytial virus prefusion F protein–based vaccine (RSVpreF) and placebo groups. In the high-income group, the preterm birth rate at a GA at birth of 24–less than 28 weeks was less than 0.1% (n=1) in the placebo group. In the non–high-income group, the preterm birth rate at a GA at birth of 24–less than 28 weeks was less than 0.1% (n=1) in the RSVpreF group. In the upper-middle–income group, the preterm birth rate at a GA at birth of 24–less than 28 weeks was less than 0.1% (n=1) in the RSVpreF group. B. Countries with more than five preterm births overall. Countries included in each income region are summarized in Appendix 2, available online at http://links.lww.com/AOG/D944 . n, number of newborns and infants born preterm; N, total number of infants.

Article Snippet: To describe preterm birth frequency and newborn and infant outcomes overall and among preterm children in the MATISSE (Maternal Immunization Study for Safety and Efficacy) trial of maternal vaccination with bivalent respiratory syncytial virus (RSV) prefusion F protein–based vaccine (RSVpreF) to protect infants against severe RSV-associated illness.

Techniques: Virus