Lot-to-lot consistency, immunogenicity, and safety of the Ad26.ZEBOV, MVA-BN-Filo Ebola virus vaccine regimen: A phase 3, randomized, double-blind, placebo-controlled trial.

This phase-3, double-blind, placebo-controlled study (NCT04228783) evaluated lot-to-lot consistency of the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen. Participants were randomized (6:6:6:1) to receive the two-dose regimen from three consecutively manufactured lots of Ad26.ZEBOV on Day 1 paired with three consecutively manufactured lots of MVA-BN-Filo on Day 57 (Groups 1-3) or two doses of placebo (Group 4). An additional cohort also received an Ad26.ZEBOV booster or placebo 4 months post-dose 2. Equivalence of the immunogenicity at 21 days post-dose 2 between any two groups was demonstrated if the 95% confidence interval (CI) of the Ebola virus glycoprotein (EBOV GP)-binding antibody geometric mean concentration (GMC) ratio was entirely within the prespecified margin of 0.5-2.0. Lot-to-lot consistency (i.e., consecutive lots can be consistently manufactured) was accomplished if equivalence was shown for all three pairwise comparisons. Results showed that the primary objective in the per-protocol immunogenicity subset (n = 549) was established for each pairwise comparison (Group 1 vs 2: GMC ratio = 0.9 [95% CI: 0.8, 1.1], Group 1 vs 3: 0.9 [0.8, 1.1], Group 2 vs 3: 1.0 [0.9, 1.2]). Equivalence of the three groups for the Ad26.ZEBOV component only was also demonstrated at 56 days post-dose 1. EBOV GP-binding antibody responses (post-vaccination concentrations >2.5-fold from baseline) were observed in 419/421 (99.5%) vaccine recipients at 21 days post-dose 2 and 445/460 (96.7%) at 56 days post-dose 1. In the booster cohort (n = 39), GMCs increased 9.0- and 11.8-fold at 7 and 21 days post-booster, respectively, versus pre-booster. Ad26.ZEBOV, MVA-BN-Filo was well tolerated, and no safety issues were identified.

Long-Term Clinical Safety of the Ad26.ZEBOV and MVA-BN-Filo Ebola Vaccines: A Prospective, Multi-Country, Observational Study.

In this prospective, observational study (ClinicalTrials.gov Identifier: NCT02661464), long-term safety information was collected from participants previously exposed to the Ebola vaccines Ad26.ZEBOV and/or MVA-BN-Filo while enrolled in phase 1, 2, or 3 clinical studies. The study was conducted at 15 sites in seven countries (Burkina Faso, France, Kenya, Tanzania, Uganda, the United Kingdom, and the United States). Adult participants and offspring from vaccinated female participants who became pregnant (estimated conception ≤28 days after vaccination with MVA-BN-Filo or ≤3 months after vaccination with Ad26.ZEBOV) were enrolled. Adults were followed for 60 months after their first vaccination, and children born to female participants were followed for 60 months after birth. In the full analysis set (n = 614 adults; median age [range]: 32.0 [18-65] years), 49 (8.0%) had ≥1 serious adverse event (SAE); the incidence rate of any SAE was 27.4 per 1000 person-years (95% confidence interval: 21.0, 35.2). The unrelated SAEs of malaria were reported in the two infants in the full analysis set, aged 11 and 18 months; both episodes were resolved. No deaths or life-threatening SAEs occurred during the study. Overall, no major safety issues were identified; one related SAE was reported. These findings support the long-term clinical safety of the Ad26.ZEBOV and MVA-BN-Filo vaccines.

Safety and immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in infants: a phase 2, randomised, double-blind, active-controlled trial in Guinea and Sierra Leone.

BACKGROUND: This study assessed the safety and immunogenicity of the Ad26.ZEBOV and MVA-BN-Filo Ebola virus (EBOV) vaccine regimen in infants aged 4-11 months in Guinea and Sierra Leone. METHODS: In this phase 2, randomised, double-blind, active-controlled trial, we randomly assigned healthy infants (1:1 in a sentinel cohort, 5:2 for the remaining infants via an interactive web response system) to receive Ad26.ZEBOV followed by MVA-BN-Filo (Ebola vaccine group) or two doses of meningococcal quadrivalent conjugate vaccine (control group) administered 56 days apart. Infants were recruited at two sites in west Africa: Conakry, Guinea, and Kambia, Sierra Leone. All infants received the meningococcal vaccine 8 months after being randomly assigned. The primary objective was safety. The secondary objective was immunogenicity, measured as EBOV glycoprotein-binding antibody concentration 21 days post-dose 2, using the Filovirus Animal Non-Clinical Group ELISA. This study is registered with ClinicalTrials.gov (NCT03929757) and the Pan African Clinical Trials Registry (PACTR201905827924069). FINDINGS: From Aug 20 to Nov 29, 2019, 142 infants were screened and 108 were randomly assigned (Ebola vaccine n=75; control n=33). The most common solicited local adverse event was injection-site pain (Ebola vaccine 15 [20%] of 75; control four [12%] of 33). The most common solicited systemic adverse events with the Ebola vaccine were irritability (26 [35%] of 75), decreased appetite (18 [24%] of 75), pyrexia (16 [21%] of 75), and decreased activity (15 [20%] of 75). In the control group, ten (30%) of 33 had irritability, seven (21%) of 33 had decreased appetite, three (9%) of 33 had pyrexia, and five (15%) of 33 had decreased activity. The frequency of unsolicited adverse events was 83% (62 of 75 infants) in the Ebola vaccine group and 85% (28 of 33 infants) in the control group. No serious adverse events were vaccine-related. In the Ebola vaccine group, EBOV glycoprotein-binding antibody geometric mean concentrations (GMCs) at 21 days post-dose 2 were 27 700 ELISA units (EU)/mL (95% CI 20 477-37 470) in infants aged 4-8 months and 20 481 EU/mL (15 325-27 372) in infants aged 9-11 months. The responder rate was 100% (74 of 74 responded). In the control group, GMCs for both age groups were less than the lower limit of quantification and the responder rate was 3% (one of 33 responded). INTERPRETATION: Ad26.ZEBOV and MVA-BN-Filo was well tolerated and induced strong humoral responses in infants younger than 1 year. There were no safety concerns related to vaccination. FUNDING: Janssen Vaccines & Prevention and Innovative Medicines Initiative 2 Joint Undertaking. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Persistence of immunological memory as a potential correlate of long-term, vaccine-induced protection against Ebola virus disease in humans.

Introduction: In the absence of clinical efficacy data, vaccine protective effect can be extrapolated from animals to humans, using an immunological biomarker in humans that correlates with protection in animals, in a statistical approach called immunobridging. Such an immunobridging approach was previously used to infer the likely protective effect of the heterologous two-dose Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen. However, this immunobridging model does not provide information on how the persistence of the vaccine-induced immune response relates to durability of protection in humans. Methods and results: In both humans and non-human primates, vaccine-induced circulating antibody levels appear to be very stable after an initial phase of contraction and are maintained for at least 3.8 years in humans (and at least 1.3 years in non-human primates). Immunological memory was also maintained over this period, as shown by the kinetics and magnitude of the anamnestic response following re-exposure to the Ebola virus glycoprotein antigen via booster vaccination with Ad26.ZEBOV in humans. In non-human primates, immunological memory was also formed as shown by an anamnestic response after high-dose, intramuscular injection with Ebola virus, but was not sufficient for protection against Ebola virus disease at later timepoints due to a decline in circulating antibodies and the fast kinetics of disease in the non-human primates model. Booster vaccination within three days of subsequent Ebola virus challenge in non-human primates resulted in protection from Ebola virus disease, i.e. before the anamnestic response was fully developed. Discussion: Humans infected with Ebola virus may benefit from the anamnestic response to prevent disease progression, as the incubation time is longer and progression of Ebola virus disease is slower as compared to non-human primates. Therefore, the persistence of vaccine-induced immune memory could be considered as a potential correlate of long-term protection against Ebola virus disease in humans, without the need for a booster.

The Effect of Previous Exposure to Malaria Infection and Clinical Malaria Episodes on the Immune Response to the Two-Dose Ad26.ZEBOV, MVA-BN-Filo Ebola Vaccine Regimen.

We assessed whether the immunogenicity of the two-dose Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen with a 56-day interval between doses was affected by exposure to malaria before dose 1 vaccination and by clinical episodes of malaria in the period immediately after dose 1 and after dose 2 vaccinations. Previous malaria exposure in participants in an Ebola vaccine trial in Sierra Leone (ClinicalTrials.gov: NCT02509494) was classified as low, intermediate, and high according to their antibody responses to a panel of Plasmodium falciparum antigens detected using a Luminex MAGPIX platform. Clinical malaria episodes after vaccinations were recorded as part of the trial safety monitoring. Binding antibody responses against the Ebola virus (EBOV) glycoprotein (GP) were measured 57 days post dose 1 and 21 days post dose 2 by ELISA and summarized as Geometric Mean Concentrations (GMCs). Geometric Mean Ratios (GMRs) were used to compare groups with different levels of exposure to malaria. Overall, 587 participants, comprising 188 (32%) adults (aged ≥ 18 years) and 399 (68%) children (aged 1-3, 4-11, and 12-17 years), were included in the analysis. There was no evidence that the anti-EBOV-GP antibody GMCs post dose 1 and post dose 2 differed between categories of previous malaria exposure. There was weak evidence that the GMC at 57 days post dose 1 was lower in participants who had had at least one episode of clinical malaria post dose 1 compared to participants with no diagnosed clinical malaria in the same period (GMR = 0.82, 95% CI: 0.69-0.98, p-value = 0.02). However, GMC post dose 2 was not reduced in participants who experienced clinical malaria post-dose 1 and/or post-dose 2 vaccinations. In conclusion, the Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen is immunogenic in individuals with previous exposure to malaria and in those who experience clinical malaria after vaccination. This vaccine regimen is suitable for prophylaxis against Ebola virus disease in malaria-endemic regions.

Immune response of a two-dose heterologous Ebola vaccine regimen: summary of three African clinical trials using a single validated Filovirus Animal Nonclinical Group enzyme-linked immunosorbent assay in a single accredited laboratory.

BACKGROUND: This analysis evaluated the immune response to the two-dose, heterologous Ad26.ZEBOV, MVA-BN-Filo Ebola virus vaccine regimen, administered 56-days apart, from multiple African sites based on results from one analytic laboratory. METHODS: Immunogenicity across three trials (EBL2002, EBL2004/PREVAC, EBL3001) conducted in East and West Africa is summarised. Vaccine-induced Ebola glycoprotein-binding antibody concentrations were analysed by Q2 Solutions laboratory at baseline, 21 days (EBL2002 and EBL3001) or 28 days (EBL2004) post-dose 2 (regimen completion), and 12 months post-dose 1 using the validated Filovirus Animal Nonclinical Group Ebola glycoprotein enzyme-linked immunosorbent assay (ELISA). Responders were defined as those with a >2.5-fold increase from baseline or the lower limit of quantification (LLOQ) if 

Safety and immunogenicity of an Ad26.ZEBOV booster dose in children previously vaccinated with the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen: an open-label, non-randomised, phase 2 trial.

BACKGROUND: Children account for a substantial proportion of cases and deaths during Ebola virus disease outbreaks. We aimed to evaluate the safety and immunogenicity of a booster dose of the Ad26.ZEBOV vaccine in children who had been vaccinated with a two-dose regimen comprising Ad26.ZEBOV as dose one and MVA-BN-Filo as dose two. METHODS: We conducted an open-label, non-randomised, phase 2 trial at one clinic in Kambia Town, Sierra Leone. Healthy children, excluding pregnant or breastfeeding girls, who had received the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen in a previous study, and were aged 1-11 years at the time of their first vaccine dose, received an intramuscular injection of Ad26.ZEBOV (5 × 1010 viral particles) and were followed up for 28 days. Primary outcomes were safety (measured by adverse events) and immunogenicity (measured by Ebola virus glycoprotein-specific IgG binding antibody geometric mean concentration) of the booster vaccine dose. Safety was assessed in all participants who received the booster vaccination; immunogenicity was assessed in all participants who received the booster vaccination, had at least one evaluable sample after the booster, and had no major protocol deviations that could have influenced the immune response. This trial is registered with ClinicalTrials.gov, NCT04711356. FINDINGS: Between July 8 and Aug 18, 2021, 58 children were assessed for eligibility and 50 (27 aged 4-7 years and 23 aged 9-15 years) were enrolled and received an Ad26.ZEBOV booster vaccination, more than 3 years after receiving dose one of the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen. The booster was well tolerated. The most common solicited local adverse event during the 7 days after vaccination was injection site pain, reported in 18 (36%, 95% CI 23-51) of 50 participants. The most common solicited systemic adverse event during the 7 days after vaccination was headache, reported in 11 (22%, 12-36) of 50 participants. Malaria was the most common unsolicited adverse event during the 28 days after vaccination, reported in 25 (50%, 36-64) of 50 participants. No serious adverse events were observed during the study period. 7 days after vaccination, the Ebola virus glycoprotein-specific IgG binding antibody geometric mean concentration was 28 561 ELISA units per mL (95% CI 20 255-40 272), which was 44 times higher than the geometric mean concentration before the booster dose. 21 days after vaccination, the geometric mean concentration reached 64 690 ELISA units per mL (95% CI 48 356-86 541), which was 101 times higher than the geometric mean concentration before the booster dose. INTERPRETATION: A booster dose of Ad26.ZEBOV in children who had received the two-dose Ad26.ZEBOV and MVA-BN-Filo vaccine regimen more than 3 years earlier was well tolerated and induced a rapid and robust increase in binding antibodies against Ebola virus. These findings could inform Ebola vaccination strategies in paediatric populations. FUNDING: Innovative Medicines Initiative 2 Joint Undertaking. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Ebola Virus Glycoprotein IgG Seroprevalence in Community Previously Affected by Ebola, Sierra Leone.

We explored the association of Ebola virus antibody seropositivity and concentration with potential risk factors for infection. Among 1,282 adults and children from a community affected by the 2014-2016 Ebola outbreak in Sierra Leone, 8% were seropositive for virus antibodies but never experienced disease symptoms. Antibody concentration increased with age.

Safety and immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in children in Sierra Leone: a randomised, double-blind, controlled trial.

BACKGROUND: Children account for a substantial proportion of cases and deaths from Ebola virus disease. We aimed to assess the safety and immunogenicity of a two-dose heterologous vaccine regimen, comprising the adenovirus type 26 vector-based vaccine encoding the Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia Ankara vector-based vaccine, encoding glycoproteins from the Ebola virus, Sudan virus, and Marburg virus, and the nucleoprotein from the Tai Forest virus (MVA-BN-Filo), in a paediatric population in Sierra Leone. METHODS: This randomised, double-blind, controlled trial was done at three clinics in Kambia district, Sierra Leone. Healthy children and adolescents aged 1-17 years were enrolled in three age cohorts (12-17 years, 4-11 years, and 1-3 years) and randomly assigned (3:1), via computer-generated block randomisation (block size of eight), to receive an intramuscular injection of either Ad26.ZEBOV (5 × 1010 viral particles; first dose) followed by MVA-BN-Filo (1 × 108 infectious units; second dose) on day 57 (Ebola vaccine group), or a single dose of meningococcal quadrivalent (serogroups A, C, W135, and Y) conjugate vaccine (MenACWY; first dose) followed by placebo (second dose) on day 57 (control group). Study team personnel (except for those with primary responsibility for study vaccine preparation), participants, and their parents or guardians were masked to study vaccine allocation. The primary outcome was safety, measured as the occurrence of solicited local and systemic adverse symptoms during 7 days after each vaccination, unsolicited systemic adverse events during 28 days after each vaccination, abnormal laboratory results during the study period, and serious adverse events or immediate reportable events throughout the study period. The secondary outcome was immunogenicity (humoral immune response), measured as the concentration of Ebola virus glycoprotein-specific binding antibodies at 21 days after the second dose. The primary outcome was assessed in all participants who had received at least one dose of study vaccine and had available reactogenicity data, and immunogenicity was assessed in all participants who had received both vaccinations within the protocol-defined time window, had at least one evaluable post-vaccination sample, and had no major protocol deviations that could have influenced the immune response. This study is registered at ClinicalTrials.gov, NCT02509494. FINDINGS: From April 4, 2017, to July 5, 2018, 576 eligible children or adolescents (192 in each of the three age cohorts) were enrolled and randomly assigned. The most common solicited local adverse event during the 7 days after the first and second dose was injection-site pain in all age groups, with frequencies ranging from 0% (none of 48) of children aged 1-3 years after placebo injection to 21% (30 of 144) of children aged 4-11 years after Ad26.ZEBOV vaccination. The most frequently observed solicited systemic adverse event during the 7 days was headache in the 12-17 years and 4-11 years age cohorts after the first and second dose, and pyrexia in the 1-3 years age cohort after the first and second dose. The most frequent unsolicited adverse event after the first and second dose vaccinations was malaria in all age cohorts, irrespective of the vaccine types. Following vaccination with MenACWY, severe thrombocytopaenia was observed in one participant aged 3 years. No other clinically significant laboratory abnormalities were observed in other study participants, and no serious adverse events related to the Ebola vaccine regimen were reported. There were no treatment-related deaths. Ebola virus glycoprotein-specific binding antibody responses at 21 days after the second dose of the Ebola virus vaccine regimen were observed in 131 (98%) of 134 children aged 12-17 years (9929 ELISA units [EU]/mL [95% CI 8172-12 064]), in 119 (99%) of 120 aged 4-11 years (10 212 EU/mL [8419-12 388]), and in 118 (98%) of 121 aged 1-3 years (22 568 EU/mL [18 426-27 642]). INTERPRETATION: The Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen was well tolerated with no safety concerns in children aged 1-17 years, and induced robust humoral immune responses, suggesting suitability of this regimen for Ebola virus disease prophylaxis in children. FUNDING: Innovative Medicines Initiative 2 Joint Undertaking and Janssen Vaccines & Prevention BV.

Safety and long-term immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in adults in Sierra Leone: a combined open-label, non-randomised stage 1, and a randomised, double-blind, controlled stage 2 trial.

BACKGROUND: The Ebola epidemics in west Africa and the Democratic Republic of the Congo highlight an urgent need for safe and effective vaccines to prevent Ebola virus disease. We aimed to assess the safety and long-term immunogenicity of a two-dose heterologous vaccine regimen, comprising the adenovirus type 26 vector-based vaccine encoding the Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia Ankara vector-based vaccine, encoding glycoproteins from Ebola virus, Sudan virus, and Marburg virus, and the nucleoprotein from the Tai Forest virus (MVA-BN-Filo), in Sierra Leone, a country previously affected by Ebola. METHODS: The trial comprised two stages: an open-label, non-randomised stage 1, and a randomised, double-blind, controlled stage 2. The study was done at three clinics in Kambia district, Sierra Leone. In stage 1, healthy adults (aged ≥18 years) residing in or near Kambia district, received an intramuscular injection of Ad26.ZEBOV (5 × 1010 viral particles) on day 1 (first dose) followed by an intramuscular injection of MVA-BN-Filo (1 × 108 infectious units) on day 57 (second dose). An Ad26.ZEBOV booster vaccination was offered at 2 years after the first dose to stage 1 participants. The eligibility criteria for adult participants in stage 2 were consistent with stage 1 eligibility criteria. Stage 2 participants were randomly assigned (3:1), by computer-generated block randomisation (block size of eight) via an interactive web-response system, to receive either the Ebola vaccine regimen (Ad26.ZEBOV followed by MVA-BN-Filo) or an intramuscular injection of a single dose of meningococcal quadrivalent (serogroups A, C, W135, and Y) conjugate vaccine (MenACWY; first dose) followed by placebo on day 57 (second dose; control group). Study team personnel, except those with primary responsibility for study vaccine preparation, and participants were masked to study vaccine allocation. The primary outcome was the safety of the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen, which was assessed in all participants who had received at least one dose of study vaccine. Safety was assessed as solicited local and systemic adverse events occurring in the first 7 days after each vaccination, unsolicited adverse events occurring in the first 28 days after each vaccination, and serious adverse events or immediate reportable events occurring up to each participant's last study visit. Secondary outcomes were to assess Ebola virus glycoprotein-specific binding antibody responses at 21 days after the second vaccine in a per-protocol set of participants (ie, those who had received both vaccinations within the protocol-defined time window, had at least one evaluable post-vaccination sample, and had no major protocol deviations that could have influenced the immune response) and to assess the safety and tolerability of the Ad26.ZEBOV booster vaccination in stage 1 participants who had received the booster dose. This study is registered at ClinicalTrials.gov, NCT02509494. FINDINGS: Between Sept 30, 2015, and Oct 19, 2016, 443 participants (43 in stage 1 and 400 in stage 2) were enrolled; 341 participants assigned to receive the Ad26.ZEBOV and MVA-BN-Filo regimen and 102 participants assigned to receive the MenACWY and placebo regimen received at least one dose of study vaccine. Both regimens were well tolerated with no safety concerns. In stage 1, solicited local adverse events (mostly mild or moderate injection-site pain) were reported in 12 (28%) of 43 participants after Ad26.ZEBOV vaccination and in six (14%) participants after MVA-BN-Filo vaccination. In stage 2, solicited local adverse events were reported in 51 (17%) of 298 participants after Ad26.ZEBOV vaccination, in 58 (24%) of 246 after MVA-BN-Filo vaccination, in 17 (17%) of 102 after MenACWY vaccination, and in eight (9%) of 86 after placebo injection. In stage 1, solicited systemic adverse events were reported in 18 (42%) of 43 participants after Ad26.ZEBOV vaccination and in 17 (40%) after MVA-BN-Filo vaccination. In stage 2, solicited systemic adverse events were reported in 161 (54%) of 298 participants after Ad26.ZEBOV vaccination, in 107 (43%) of 246 after MVA-BN-Filo vaccination, in 51 (50%) of 102 after MenACWY vaccination, and in 39 (45%) of 86 after placebo injection. Solicited systemic adverse events in both stage 1 and 2 participants included mostly mild or moderate headache, myalgia, fatigue, and arthralgia. The most frequent unsolicited adverse event after the first dose was headache in stage 1 and malaria in stage 2. Malaria was the most frequent unsolicited adverse event after the second dose in both stage 1 and 2. No serious adverse event was considered related to the study vaccine, and no immediate reportable events were observed. In stage 1, the safety profile after the booster vaccination was not notably different to that observed after the first dose. Vaccine-induced humoral immune responses were observed in 41 (98%) of 42 stage 1 participants (geometric mean binding antibody concentration 4784 ELISA units [EU]/mL [95% CI 3736-6125]) and in 176 (98%) of 179 stage 2 participants (3810 EU/mL [3312-4383]) at 21 days after the second vaccination. INTERPRETATION: The Ad26.ZEBOV and MVA-BN-Filo vaccine regimen was well tolerated and immunogenic, with persistent humoral immune responses. These data support the use of this vaccine regimen for Ebola virus disease prophylaxis in adults. FUNDING: Innovative Medicines Initiative 2 Joint Undertaking and Janssen Vaccines & Prevention BV.

Safety, reactogenicity, and immunogenicity of a chimpanzee adenovirus vectored Ebola vaccine in adults in Africa: a randomised, observer-blind, placebo-controlled, phase 2 trial.

BACKGROUND: The 2014 Zaire Ebola virus disease epidemic accelerated vaccine development for the virus. We aimed to assess the safety, reactogenicity, and immunogenicity of one dose of monovalent, recombinant, chimpanzee adenovirus type-3 vectored Zaire Ebola glycoprotein vaccine (ChAd3-EBO-Z) in adults. METHODS: This phase 2, randomised, observer-blind, controlled trial was done in study centres in Cameroon, Mali, Nigeria, and Senegal. Healthy adults (≥18 years) were randomly assigned with a web-based system (1:1; minimisation procedure accounting for age, gender, centre) to receive ChAd3-EBO-Z (day 0), or saline placebo (day 0) and ChAd3-EBO-Z (month 6). The study was observer-blind until planned interim day 30 analysis, single-blind until month 6, and open-label after month 6 vaccination. Primary outcomes assessed in the total vaccinated cohort, which comprised all participants with at least one study dose administration documented, were serious adverse events (up to study end, month 12); and for a subcohort were solicited local or general adverse events (7 days post-vaccination), unsolicited adverse events (30 days post-vaccination), haematological or biochemical abnormalities, and clinical symptoms of thrombocytopenia (day 0-6). Secondary endpoints (subcohort; per-protocol cohort) evaluated anti-glycoprotein Ebola virus antibody titres (ELISA) pre-vaccination and 30 days post-vaccination. This study is registered with ClinicalTrials.gov, NCT02485301. FINDINGS: Between July 22, 2015, and Dec 10, 2015, 3030 adults were randomly assigned; 3013 were included in the total vaccinated cohort (1509 [50·1%] in the ChAd3-EBO-Z group and 1504 [49·9%] in the placebo/ChAd3-EBO-Z group), 17 were excluded because no vaccine was administered. The most common solicited injection site symptom was pain (356 [48%] of 748 in the ChAd3-EBO-Z group vs 57 [8%] of 751 in the placebo/ChAd3-EBO-Z group); the most common solicited general adverse event was headache (345 [46%] in the ChAd3-EBO-Z group vs 136 [18%] in the placebo/ChAd3-EBO-Z group). Unsolicited adverse events were reported by 123 (16%) of 749 in the ChAd3-EBO-Z group and 119 (16%) of 751 in the placebo/ChAd3-EBO-Z group. Serious adverse events were reported for 11 (1%) of 1509 adults in the ChAd3-EBO-Z group, and 18 (1%) of 1504 in the placebo/ChAd3-EBO-Z group; none were considered vaccination-related. No clinically meaningful thrombocytopenia was reported. At day 30, anti-glycoprotein Ebola virus antibody geometric mean concentration was 900 (95% CI 824-983) in the ChAd3-EBO-Z group. There were no treatment-related deaths. INTERPRETATION: ChAd3-EBO-Z was immunogenic and well tolerated in adults. Our findings provide a strong basis for future development steps, which should concentrate on multivalent approaches (including Sudan and Marburg strains). Additionally, prime-boost approaches should be a focus with a ChAd3-based vaccine for priming and boosted by a modified vaccinia Ankara-based vaccine. FUNDING: EU's Horizon 2020 research and innovation programme and GlaxoSmithKline Biologicals SA.

Safety, reactogenicity, and immunogenicity of a chimpanzee adenovirus vectored Ebola vaccine in children in Africa: a randomised, observer-blind, placebo-controlled, phase 2 trial.

BACKGROUND: During the large 2013-16 Ebola virus outbreak caused by the Zaire Ebola virus, about 20% of cases were reported in children. This study is the first, to our knowledge, to evaluate an Ebola vaccine in children younger than 6 years. We aimed to evaluate the safety, reactogenicity, and immunogenicity of a monovalent, recombinant, chimpanzee adenovirus type-3 vectored Zaire Ebola glycoprotein vaccine (ChAd3-EBO-Z) in a paediatric population. METHODS: This phase 2, randomised, observer-blind, controlled trial was done in a vaccine centre in Mali and a university hospital centre in Senegal. Healthy children were randomly assigned through a web-based system (1:1; stratified by age group, gender, and centre) to receive ChAd3-EBO-Z (day 0) and meningococcal serogroups A,C,W-135,Y tetanus toxoid conjugate vaccine (MenACWY-TT; month 6), or MenACWY-TT (day 0) and ChAd3-EBO-Z (month 6). The study was observer-blind from study start until interim day 30 analysis and became single-blind as of interim analysis. Primary outcomes assessed were serious adverse events (up to study end, month 12), solicited local or general adverse events (7 days post-vaccination), unsolicited adverse events (30 days post-vaccination), haematological or biochemical abnormalities, and clinical symptoms of thrombocytopenia (day 0-6). As secondary endpoints, we evaluated anti-glycoprotein Zaire Ebola virus antibody titres (ELISA) pre-vaccination and 30 days post-vaccination. This study is registered with ClinicalTrials.gov, NCT02548078. FINDINGS: From Nov 11, 2015, to May 9, 2016, of 776 children screened for eligibility, 600 were randomly assigned (200 [33%] in each age strata: 1-5, 6-12, 13-17 years), 300 (50%) to the ChAd3-EBO-Z/MenACWY-TT group and 300 (50%) to the MenACWY-TT/ChAd3-EBO-Z group; all were included in the total vaccinated cohort. Post-day 0 vaccination, the most common solicited injection site symptom was pain (127 [42%] of 300 in the ChAd3-EBO-Z/MenACWY-TT group vs 60 [20%] of 300 in the MenACWY-TT/ChAd3-EBO-Z group); the most common solicited general adverse event was fever (95 [32%] of 300 in the ChAd3-EBO-Z/MenACWY-TT group vs 28 [9%] of 300 in the MenACWY-TT/ChAd3-EBO-Z group). Unsolicited adverse events post-day 0 vaccination were reported by 41 (14%) of 300 participants in the ChAd3-EBO-Z/MenACWY-TT group and 24 (8%) of 300 MenACWY-TT/ChAd3-EBO-Z recipients. Serious adverse events were reported for two (1%) of 300 children in each group; none were considered vaccination related. No clinical symptoms of thrombocytopenia were reported. At day 30, anti-glycoprotein Ebola virus antibody geometric mean concentrations (GMC) in the ChAd3-EBO-Z/MenACWY-TT group were 1564 (95% CI 1340-1826) for those aged 13-17 years, 1395 (1175-1655) for 6-12 years, and 2406 (1942-2979) for 1-5 years. Anti-glycoprotein Ebola virus IgG antibody responses persisted up to 12 months post-vaccination, with a GMC of 716 (95% CI 619-828) for those aged 13-17 years, 752 (645-876) for 6-12 years, and 1424 (1119-1814) for 1-5 years. INTERPRETATION: ChAd3-EBO-Z was immunogenic and well tolerated in children aged 1-17 years. This study provides the first ChAd3-EBO-Z data in a paediatric population. Further development should focus on multivalent approaches including Sudan and Marburg strains, and heterologous prime-boost strategies, for instance using modified vaccinia Ankara-based vaccine to boost the immune response. FUNDING: EU's Horizon 2020 research and innovation programme and GlaxoSmithKline Biologicals SA.

HIV virologic failure and its predictors among HIV-infected adults on antiretroviral therapy in the African Cohort Study.

INTRODUCTION: The 2016 WHO consolidated guidelines on the use of antiretroviral drugs defines HIV virologic failure for low and middle income countries (LMIC) as plasma HIV-RNA ≥ 1000 copies/mL. We evaluated virologic failure and predictors in four African countries. MATERIALS AND METHODS: We included HIV-infected participants on a WHO recommended antiretroviral therapy (ART) regimen and enrolled in the African Cohort Study between January 2013 and October 2017. Studied outcomes were virologic failure (plasma HIV-RNA ≥ 1000 copies/mL at the most recent visit), viraemia (plasma HIV-RNA ≥ 50 copies/mL at the most recent visit); and persistent viraemia (plasma HIV-RNA ≥ 50 copies/mL at two consecutive visits). Generalized linear models were used to estimate relative risks with their 95% confidence intervals. RESULTS: 2054 participants were included in this analysis. Viraemia, persistent viraemia and virologic failure were observed in 396 (19.3%), 160 (7.8%) and 184 (9%) participants respectively. Of the participants with persistent viraemia, only 57.5% (92/160) had confirmed virologic failure. In the multivariate analysis, attending clinical care site other than the Uganda sitebeing on 2nd line ART (aRR 1.8, 95% CI 1·28-2·66); other ART combinations not first line and not second line (aRR 3.8, 95% CI 1.18-11.9), a history of fever in the past week (aRR 3.7, 95% CI 1.69-8.05), low CD4 count (aRR 6.9, 95% CI 4.7-10.2) and missing any day of ART (aRR 1·8, 95% CI 1·27-2.57) increased the risk of virologic failure. Being on 2nd line therapy, the site where one receives care and CD4 count < 500 predicted viraemia, persistent viraemia and virologic failure. CONCLUSION: In conclusion, these findings demonstrate that HIV-infected patients established on ART for more than six months in the African setting frequently experienced viraemia while continuing to be on ART. The findings also show that being on second line, low CD4 count, missing any day of ART and history of fever in the past week remain important predictors of virologic failure that should trigger intensified adherence counselling especially in the absence of reliable or readily available viral load monitoring. Finally, clinical care sites are different calling for further analyses to elucidate on the unique features of these sites.

Time to change the paradigm: limited condom and lubricant use among Nigerian men who have sex with men and transgender women despite availability and counseling.

PURPOSE: This study characterized availability and uptake of condoms and condom-compatible lubricants (CCLs) at community-engaged condom education and distribution programs serving cisgender men who have sex with men and transgender women in Abuja and Lagos, Nigeria. METHODS: Condoms and water-based CCLs were freely available to participants in the TRUST/RV368 cohort. Factors associated with their consistent use were assessed using Poisson regression with robust error variance to estimate relative risks (RRs) and 95% confidence intervals (CIs). RESULTS: From March 2013-November 2017, 2090 cisgender men who have sex with men and transgender women enrolled with HIV prevalence 40.4% and incidence 12.8 cases per 100 person-years. Fifteen months after enrollment, the proportion who reported consistent condom and CCL use increased during receptive anal sex (21.7%-67.1%, P < .001) and insertive anal sex (25.4%-67.8%, P < .001). Multivariable analyses demonstrated independent impact of 15 months in care on uptake during both receptive (RR 2.62 [95% CI 2.29-3.00]) and insertive (RR 2.27 [95% CI 2.01-2.57]) sex. CONCLUSIONS: Engagement in care improved condom and CCL uptake over time but inconsistent use remained common. Novel approaches to further increase uptake must be pursued alongside complementary strategies, such as sustained access to antiretroviral therapy for those living with HIV and provision of pre and postexposure prophylaxis for those at risk.

Noninfectious Comorbidity in the African Cohort Study.

BACKGROUND: Noninfectious comorbid diseases (NCDs) contribute to morbidity and mortality in human immunodeficiency virus (HIV)-infected populations in resource-rich countries. With antiretroviral therapy (ART) scale-up in Africa, understanding burden NCD informs public health strategy. METHODS: At enrollment, participants at 11 HIV clinics in Kenya, Uganda, Tanzania, and Nigeria underwent medical history, physical, laboratory, and neuropsychological assessments to identify elevated blood pressure, hypercholesterolemia, dysglycemia, renal insufficiency, and cognitive impairment. Poisson regression models estimated adjusted relative risks (ARRs) and 95% confidence intervals (CIs) for the number of NCDs associated with factors of interest. Logistic regression was used to evaluate each NCD separately among HIV-infected participants. RESULTS: Among 2720 participants with complete NCD data, 2159 (79.4%) were HIV-infected. Of those, 1426 (66.0%) were taking ART and 813 (37.7%) had at least 1 NCD. HIV infection was associated with more NCDs, especially with ART (ARR, 1.42; 95% CI, 1.22-1.66). In addition to age, body mass index, and program site, ART usage was associated with more NCDs (ARR, 1.50; 95% CI, 1.27-1.78 for virologically suppressed and ARR, 1.38; 95% CI, 1.13-1.68 for viremic) among HIV-infected participants. In participants taking ART, CD4 nadir below 200 cells/mm3 was associated with more NCDs (ARR, 1.43; 95% CI, 1.06-1.93). ART use was independently associated with hypercholesterolemia and dysglycemia. Program site was significantly associated with all comorbidities except renal insufficiency. CONCLUSIONS: HIV infection was a risk for NCDs, which were common in HIV-infected participants, geographically variable, and largely consistent with metabolic complications of first-line ART.

Stigma, access to healthcare, and HIV risks among men who sell sex to men in Nigeria.

INTRODUCTION: Among men who have sex with men (MSM), men who sell sex (MSS) may be subject to increased sexual behaviour-related stigma that affects uptake of healthcare and risk of sexually transmitted infections (STIs). The objectives of this study were to characterize stigma, access to care, and prevalence of HIV among MSS in Nigeria. METHODS: Respondent-driven sampling was used to recruit MSM in Abuja and Lagos into the ongoing TRUST/RV368 study, which provides HIV testing and treatment. Detailed behavioural data were collected by trained interviewers. MSS were identified by self-report of receiving goods or money in exchange for sex with men. Poisson regression with robust error variance was used to explore the impact of sex-selling on the risk of HIV. RESULTS: From 12 initial seed participants, 1552 men were recruited from March 2013-March 2016. Of these, 735 (47.4%) reported sex-selling. Compared to other MSM, MSS were younger (median 22 vs. 24 years, p < 0.001) and more likely to identify as gay/homosexual (42.4% vs. 31.5%, p < 0.001). MSS were more likely to report perceived and experienced stigmas such as healthcare avoidance (27.6% vs. 21.5%, p = 0.005) and verbal harassment (39.2% vs. 26.8%, p < 0.001). Total HIV prevalence was 53.4%. After controlling for other factors, HIV prevalence among MSS was similar to that observed among other MSM (relative risk 0.94 [95% confidence interval 0.84-1.05]). CONCLUSION: These data highlight increased sexual behaviour-related stigma affecting MSS, as compared with other MSM, that limits uptake of healthcare services. The distinct characteristics and risks among MSS suggest the need for specific interventions to optimize linkage to HIV prevention and treatment services in Nigeria.

High prevalence of HIV, chlamydia and gonorrhoea among men who have sex with men and transgender women attending trusted community centres in Abuja and Lagos, Nigeria.

INTRODUCTION: Sexually transmitted infection (STI) and HIV prevalence have been reported to be higher amongst men who have sex with men (MSM) in Nigeria than in the general population. The objective of this study was to characterize the prevalence of HIV, chlamydia and gonorrhoea in this population using laboratory-based universal testing. METHODS: TRUST/RV368 represents a cohort of MSM and transgender women (TGW) recruited at trusted community centres in Abuja and Lagos, Nigeria, using respondent-driven sampling (RDS). Participants undergo a structured comprehensive assessment of HIV-related risks and screening for anorectal and urogenital Chlamydia trachomatis and Neisseria gonorrhoeae, and HIV. Crude and RDS-weighted prevalence estimates with 95% confidence intervals (CIs) were calculated. Log-binomial regression was used to explore factors associated with prevalent HIV infection and STIs. RESULTS: From March 2013 to January 2016, 862 MSM and TGW (316 in Lagos and 546 in Abuja) underwent screening for HIV, chlamydia and gonorrhoea at study enrolment. Participants' median age was 24 years [interquartile range (IQR) 21-27]. One-third (34.2%) were identified as gay/homosexual and 65.2% as bisexual. The overall prevalence of HIV was 54.9%. After adjusting for the RDS recruitment method, HIV prevalence in Abuja was 43.5% (95% CI 37.3-49.6%) and in Lagos was 65.6% (95% CI 54.7-76.5%). The RDS-weighted prevalence of chlamydia was 17.0% (95% CI 11.8-22.3%) in Abuja and 18.3% (95% CI 11.1-25.4%) in Lagos. Chlamydia infection was detected only at the anorectal site in 70.2% of cases. The RDS-weighted prevalence of gonorrhoea was 19.1% (95% CI 14.6-23.5%) in Abuja and 25.8% (95% CI 17.1-34.6%) in Lagos. Overall, 84.2% of gonorrhoea cases presented with anorectal infection only. Over 95% of STI cases were asymptomatic. In a multivariable model, increased risk for chlamydia/gonorrhoea was associated with younger age, gay/homosexual sexual orientation and higher number of partners for receptive anal sex. HIV infection was associated with older age, female gender identity and number of partners for receptive anal sex. CONCLUSIONS: There is a high burden of infection with HIV and asymptomatic chlamydia and gonorrhoea among MSM and TGW in Nigeria. Most cases would have been missed without anorectal screening. Interventions are needed to target this population for appropriate STI screening and management beginning at a young age.

The immediate eff ect of the Same-Sex Marriage Prohibition Act on stigma, discrimination, and engagement on HIV prevention and treatment services in men who have sex with men in Nigeria: analysis of prospective data from the TRUST cohort.

BACKGROUND: In January, 2014, the Same-Sex Marriage Prohibition Act was signed into law in Nigeria, further criminalising same-sex sexual relationships. We aimed to assess the immediate effect of this prohibition act on stigma, discrimination, and engagement in HIV prevention and treatment services in men who have sex with men (MSM) in Nigeria. METHODS: The TRUST cohort study uses respondent-driven sampling to assess the feasibility and effectiveness of engagement of MSM in HIV prevention and treatment services at a clinical site located with a community-based organisation trusted by the MSM community. TRUST is a prospective implementation research cohort of MSM (≥16 years) in Abuja, Nigeria. We compared HIV clinical outcomes and stigma, including fear and avoidance of health care, across baseline and quarterly visits before and after implementation of the the Same-Sex Marriage Prohibition Act. Outcomes assessed were measures of stigma and discrimination, loss to follow-up, antiretroviral therapy status, and viral load. We compared outcomes before and after the legislation with χ2 statistics, and estimated incident stigma-related events and loss to follow-up with Poisson regression. FINDINGS: Between March 19, 2013, and Aug 7, 2014, 707 MSM participated in baseline study procedures, contributing to 756 before legislation (prelaw) and 420 after legislation (postlaw) visits. Reported history of fear of seeking health care was significantly higher in postlaw visits than in prelaw visits (n=161 [38%] vs n=187 [25%]; p<0・0001), as was avoidance of health care (n=118 [28%] vs n=151 [20%]; p=0・001). In incidence analyses, of 192 MSM with follow-up data and no history of an event at baseline, reported fear of seeking health care was higher in the postlaw than the prelaw period (n=144; incidence rate ratio 2・57, 95% CI 1・29­5・10; p=0・007); loss to follow-up and incident healthcare avoidance were similar across periods. Of the 161 (89%) of 181 HIV-infected MSM with HIV viral loads available, those who had disclosed sexual behaviour with a health-care provider were more often virally suppressed at baseline than those with no previous disclosure (18 [29%] of 62 vs 13 [13%] of 99 men; p=0・013). INTERPRETATION: These analyses represent individual-level, quantitative, real-time prospective data for the health-related effects resulting from the enactment of legislation further criminalising same-sex practices. The negative effects of HIV treatment and care in MSM reinforce the unintended consequences of such legislation on global goals of HIV eradication. Strategies to reach MSM less likely to engage in HIV testing and care in highly stigmatised environments are needed to reduce time to HIV diagnosis and treatment. FUNDING: National Institutes of Health.

Uptake of treatment as prevention for HIV and continuum of care among HIV-positive men who have sex with men in Nigeria.

BACKGROUND: Experimental evidence has shown that treatment of HIV infection with antiretroviral therapy (ART) prevents heterosexual transmission of HIV to an uninfected partner. However, the "real-world" application of this strategy to key populations such as men who have sex with men (MSM) has been limited. We report findings on acceptability of a treatment as prevention (TasP) strategy among HIV-infected MSM at a Trusted Community Center providing comprehensive HIV prevention and treatment services to MSM in Abuja, Nigeria. METHODS: Using respondent-driven sampling (RDS), MSM who were 16 years and older and have engaged in either receptive or insertive anal intercourse within the previous 12 months were recruited into a prospective combination HIV prevention and treatment study (TRUST). Two weeks after enrollment, HIV testing and counseling was conducted. At each 3-month follow-up visits, HIV-infected individuals underwent clinical and laboratory evaluation, including CD4 count, plasma HIV viral load, immediate 3 weekly sessions of ART preparation, and then ART initiation per TasP strategy irrespective of CD4 count. Reasons for not engaging in pre-TasP preparation and TasP were documented. Characteristics associated with TasP engagement and loss to follow-up (LTFU) were determined using logistic and Cox regression, respectively. RESULTS: Of 186 HIV-positive MSM enrolled, 58 (31.2%) were on ART at the time of recruitment, whereas 128 (68.8%) were ART-naive and provided opportunity for engaging TasP. Of these, 70 (54.7%) engaged in TasP. Compared with MSM who did not engage in TasP, those who engaged had significantly lower mean CD4 count (P = 0.001), were more likely to be Christian (P = 0.01), and had disclosed being MSM to family (P = 0.02) or health care providers (P = 0.02). In multivariate models, disclosure of being MSM to health care providers remained significantly associated with uptake of TasP. Among individuals engaged in TasP, 10% were LTFU in care at 18 months since enrollment. Being engaged in TasP (relative hazards = 0.08, P < 0.001) and on ART (relative hazards = 0.17, P < 0.001) were associated with decreased risk of LTFU. CONCLUSIONS: Although there was high acceptance of HIV testing and low LTFU among individuals who were already on ART or engaged in TasP, a higher than expected proportion did not engage in TasP, suggesting the need for customized treatment preparation and an increase in enabling environments to support HIV treatment access with this key population.

Short communication: east meets west: a description of HIV-1 drug resistance mutation patterns of patients failing first line therapy in PEPFAR clinics from Uganda and Nigeria.

HIV-1 viral load (VL) monitoring is recommended but seldom performed in resource-constrained countries. An evaluation of patients receiving first-line antiretroviral therapy in a multicountry PEPFAR program (RV288) was performed to determine the rates and predictors of virologic suppression. Resistance data from treatment failures are available from Uganda and Nigeria. Each country enrolled 325 subjects into this cross-sectional study. Subjects on first-line therapy were randomly selected for HIV RNA testing (viral load). Regimens included efavirenz or nevirapine with zidovudine/lamivudine or tenofovir/lamivudine. VL was determined from plasma using the Roche COBAS TaqMan HIV-1 Test, High Pure System v1.0 (47 copies/ml). Genotypic resistance testing was performed on samples with VL>1,000 copies/ml. From Uganda, 85% of subjects were undetectable while 7% (23/325) had VL>1,000 copies/ml. The HIV-1 subtype distribution was as follows: A=47.6%, C=14.3%, and D=38.1%. No resistance mutations were found in 14% of subjects. All subjects with resistance had the M184V mutation. Of subjects failing a zidovudine regimen less than 1 year, 88% (7/8) had no thymidine analogue mutations (TAMs), compared to 50% (4/8) failing greater than 1 year. Four subjects (25%) had more than two mutations from the TAM-1 pathway (41L, 210W, 215Y). In Nigeria, 82% were undetectable while 14% (45/325) had VL>1,000 copies/ml. HIV-1 subtype distribution was as follows: 62.8%=CRF02_AG, 34%=pure G, and 2.8%=A. Of the 35 genotyped subjects, 14% (5/35) had no resistance mutations. Of the remainder, 10% (3/30) had no nucleoside analogue mutations while 33% (10/30) had only M184V along with nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations. Forty percent (10/25) of subjects on zidovudine failed without TAMs. Another 25% (5/25) of subjects failing on zidovudine had more than two TAM-1 mutations. Individuals failing first-line antiretroviral therapy (ART) may retain sensitivity to one or more nucleoside analogues from the regimen. Knowledge of drug resistance patterns allow for selection of drugs that can be recycled in future regimens. Accumulation of resistance mutations may compromise future treatment options.