Background Ebola vaccine development was accelerated in response to the 2014 Ebola virus infection outbreak. This phase 1 study (VAC52150EBL1004) assessed safety, tolerability, and immunogenicity of heterologous 2-dose Ad26.ZEBOV, MVA-BN-Filo vaccination regimens in the Lake Victoria Basin of Tanzania and Uganda in mid-level altitude, malaria-endemic settings. Methods Healthy volunteers aged 18–50 years from Tanzania (n = 25) and Uganda (n = 47) were randomized to receive placebo or active vaccination with Ad26.ZEBOV or MVA-BN-Filo (first vaccination), followed by MVA-BN-Filo or Ad26.ZEBOV (second vaccination) dose 2, respectively, with intervals of 28 or 56 days. Results Seventy-two adults were randomized to receive vaccine (n = 60) or placebo (n = 12). No vaccine-related serious adverse events were reported. The most frequent solicited local and systemic adverse events were injection site pain (frequency, 70%, 66%, and 42% per dose for MVA-BN-Filo, Ad26.ZEBOV, and placebo, respectively) and headache (57%, 56%, and 46%, respectively). Adverse event patterns were similar among regimens. Twenty-one days after dose 2, 100% of volunteers demonstrated binding antibody responses against Ebola virus glycoprotein, and 87%–100% demonstrated neutralizing antibody responses. Ad26.ZEBOV dose 1 vaccination induced more-robust initial binding antibody and cellular responses than MVA-BN-Filo dose 1 vaccination. Conclusions Heterologous 2-dose vaccination with Ad26.ZEBOV and MVA-BN-Filo against Ebola virus is well tolerated and immunogenic in healthy volunteers. Clinical trials registration NCT02376400.

Background We investigated safety, tolerability, and immunogenicity of the heterologous 2-dose Ebola vaccination regimen in healthy and HIV-infected adults with different intervals between Ebola vaccinations. Methods and findings In this randomised, observer-blind, placebo-controlled Phase II trial, 668 healthy 18- to 70-year-olds and 142 HIV-infected 18- to 50-year-olds were enrolled from 1 site in Kenya and 2 sites each in Burkina Faso, Cote d’Ivoire, and Uganda. Participants received intramuscular Ad26.ZEBOV followed by MVA-BN-Filo at 28-, 56-, or 84-day intervals, or saline. Females represented 31.4% of the healthy adult cohort in contrast to 69.7% of the HIV-infected cohort. A subset of healthy adults received booster vaccination with Ad26.ZEBOV or saline at Day 365. Following vaccinations, adverse events (AEs) were collected until 42 days post last vaccination and serious AEs (SAEs) were recorded from signing of the ICF until the end of the study. The primary endpoint was safety, and the secondary endpoint was immunogenicity. Anti-Ebola virus glycoprotein (EBOV GP) binding and neutralising antibodies were measured at baseline and at predefined time points throughout the study. The first participant was enrolled on 9 November 2015, and the date of last participant’s last visit was 12 February 2019. No vaccine-related SAEs and mainly mild-to-moderate AEs were observed among the participants. The most frequent solicited AEs were injection-site pain (local), and fatigue, headache, and myalgia (systemic), respectively. Twenty-one days post-MVA-BN-Filo vaccination, geometric mean concentrations (GMCs) with 95% confidence intervals (CIs) of EBOV GP binding antibodies in healthy adults in 28-, 56-, and 84-day interval groups were 3,085 EU/mL (2,648 to 3,594), 7,518 EU/mL (6,468 to 8,740), and 7,300 EU/mL (5,116 to 10,417), respectively. In HIV-infected adults in 28- and 56-day interval groups, GMCs were 4,207 EU/mL (3,233 to 5,474) and 5,283 EU/mL (4,094 to 6,817), respectively. Antibody responses were observed until Day 365. Ad26.ZEBOV booster vaccination after 1 year induced an anamnestic response. Study limitations include that some healthy adult participants either did not receive dose 2 or received dose 2 outside of their protocol-defined interval and that the follow-up period was limited to 365 days for most participants. Conclusions Ad26.ZEBOV, MVA-BN-Filo vaccination was well tolerated and immunogenic in healthy and HIV-infected African adults. Increasing the interval between vaccinations from 28 to 56 days improved the magnitude of humoral immune responses. Antibody levels persisted to at least 1 year, and Ad26.ZEBOV booster vaccination demonstrated the presence of vaccination-induced immune memory. These data supported the approval by the European Union for prophylaxis against EBOV disease in adults and children ≥1 year of age. Trial registration ClinicalTrials.gov NCT02564523

Background Reoccurring Ebola outbreaks in West and Central Africa have led to serious illness and death in thousands of adults and children. The objective of this study was to assess safety, tolerability, and immunogenicity of the heterologous 2-dose Ad26.ZEBOV, MVA-BN-Filo vaccination regimen in adolescents and children in Africa. Methods and findings In this multicentre, randomised, observer-blind, placebo-controlled Phase II study, 131 adolescents (12 to 17 years old) and 132 children (4 to 11 years old) were enrolled from Eastern and Western Africa and randomised 5:1 to receive study vaccines or placebo. Vaccine groups received intramuscular injections of Ad26.ZEBOV (5 × 1010 viral particles) and MVA-BN-Filo (1 × 108 infectious units) 28 or 56 days apart; placebo recipients received saline. Primary outcomes were safety and tolerability. Solicited adverse events (AEs) were recorded until 7 days after each vaccination and serious AEs (SAEs) throughout the study. Secondary and exploratory outcomes were humoral immune responses (binding and neutralising Ebola virus [EBOV] glycoprotein [GP]-specific antibodies), up to 1 year after the first dose. Enrolment began on February 26, 2016, and the date of last participant last visit was November 28, 2018. Of the 263 participants enrolled, 217 (109 adolescents, 108 children) received the 2-dose regimen, and 43 (20 adolescents, 23 children) received 2 placebo doses. Median age was 14.0 (range 11 to 17) and 7.0 (range 4 to 11) years for adolescents and children, respectively. Fifty-four percent of the adolescents and 51% of the children were male. All participants were Africans, and, although there was a slight male preponderance overall, the groups were well balanced. No vaccine-related SAEs were reported; solicited AEs were mostly mild/moderate. Twenty-one days post-MVA-BN-Filo vaccination, binding antibody responses against EBOV GP were observed in 100% of vaccinees (106 adolescents, 104 children). Geometric mean concentrations tended to be higher after the 56-day interval (adolescents 13,532 ELISA units [EU]/mL, children 17,388 EU/mL) than the 28-day interval (adolescents 6,993 EU/mL, children 8,007 EU/mL). Humoral responses persisted at least up to Day 365. A limitation of the study is that the follow-up period was limited to 365 days for the majority of the participants, and so it was not possible to determine whether immune responses persisted beyond this time period. Additionally, formal statistical comparisons were not preplanned but were only performed post hoc. Conclusions The heterologous 2-dose vaccination was well tolerated in African adolescents and children with no vaccine-related SAEs. All vaccinees displayed anti-EBOV GP antibodies after the 2-dose regimen, with higher responses in the 56-day interval groups. The frequency of pyrexia after vaccine or placebo was higher in children than in adolescents. These data supported the prophylactic indication against EBOV disease in a paediatric population, as licenced in the EU. Trial registration ClinicalTrials.gov NCT02564523.

IntroductionCotrimoxazole (CTX) prophylaxis is recommended by the World Health Organisation for HIV infected persons. However, once HIV infected patients have commenced ART in resource limited settings, the benefits of continued CTX prophylaxis are not known. The few studies that investigated the safety of discontinuing CTX prophylaxis in these settings had limitations due to their design.Materials and methodsCOSTOP is a randomised double blind placebo controlled non-inferiority trial among HIV infected Ugandan adults stabilised on anti-retroviral treatment (ART). Participants with CD4 count of 250 or more cells/mm3 are randomised to two arms: the intervention arm in which CTX is discontinued and the control arm in which CTX prophylaxis is continued. The study aims to assess whether the intervention regimen is not inferior, with respect to the incidence of pre-defined CTX-preventable events, to the control regimen and superior with respect to the incidence of haematological adverse events.DiscussionStudies that have previously evaluated the safety of discontinuing CTX prophylaxis among HIV infected adults in resource limited settings have provided moderate to low quality evidence owing in part to methodological limitations. COSTOP is designed and conducted with sufficient rigour to answer this question. The results of the trial will assist in guiding policy recommendations.ConclusionThis paper describes the design and methodological considerations important for the conduct of CTX cessation studies.

Introduction:Previous unblinded trials have shown increased malaria among HIV-infected adults on antiretroviral therapy (ART) who stop cotrimoxazole (CTX) prophylaxis. We investigated the effect of stopping CTX on malaria in HIV-infected adults on ART in a double-blind, placebo-controlled trial.Methods:HIV-infected Ugandan adults stable on ART and CTX with CD4+ cell count at least 250 cells/μl were randomized (1 : 1) to continue CTX or stop CTX and receive matching placebo (COSTOP trial; ISRCTN44723643). Clinical malaria was defined as fever and a positive blood slide, and considered severe if a participant had at least one clinical or laboratory feature of severity or was admitted to hospital. Malaria incidence and rate ratios were estimated using random effects Poisson regression, accounting for multiple episodes.Results:A total of 2180 participants were enrolled and followed for a median of 2.5 years; 453 malaria episodes were recorded. Malaria incidence was 9.1/100 person-years (pyrs) [95% confidence interval (CI) = 8.2–10.1] and was higher on placebo (rate ratio 3.47; CI = 2.74–4.39). Malaria in the placebo arm decreased over time; although incidence remained higher than in the CTX arm, the difference between arms reduced slightly (interaction P value = 0.10). Fifteen participants experienced severe malaria (<1%); overall incidence was 0.30/100 pyrs (CI = 0.18–0.49). There was one malaria-related death (CTX arm).Conclusion:HIV-infected adults – who are stable on ART and stop prophylactic CTX – experience more malaria than those that continue, but this difference is less than has been reported in previous trials. Few participants had severe malaria. Further research might be useful in identifying groups that can safely stop CTX prophylaxis.

BackgroundCryptococcal meningitis (CCM) remains a leading cause of mortality amongst HIV infected patients in sub-Saharan Africa. When patients receive recommended therapy, mortality at 10 weeks has been reported to vary between 20 to 36%. However, mortality rate and factors affecting mortality after completing recommended therapy are not well known. We investigated mortality rate, and factors affecting mortality at 2 years among CCM patients following completion of recommended CCM therapy in Uganda.MethodsA retrospective cohort study was conducted among HIV infected patients that had completed 10 weeks of recommended therapy for CCM (2 weeks of intravenous amphotericin B 1mg/kg and 10 weeks of oral Fluconazole 800mg daily) in the CryptoDex trial (ISRCTN59144167) between 2013 and 2015. Survival analysis applying Cox regression was used to determine the mortality rate and factors affecting mortality at 2 years.ResultsThis study followed up 112 participants for 2 years. Mean age (±SD) was 34.9 ± 8, 48 (57.1%) were female and 80 (74.8%) had been on ART for less than 1 year. At 2 years, overall mortality was 30.9% (20 deaths per 100 person-years). Majority of deaths (61.8%) occurred during the first 6 months. In multivariable analysis, mortality was associated with ever being re-admitted since discharge after hospital-based management of CCM (aHR = 13.33, 95% CI: 5.92–30.03), p<0.001; and self-perceived quality of life, with quality of life 50–75% having reduced risk compared to <50% (aHR = 0.21, 95% CI: 0.09–0.5), p<0.001, as well as >75% compared to <50% (HR = 0.29, 95% CI: 0.11–0.81), p = 0.018.ConclusionThere remains a considerable risk of mortality in the first two years after completion of standard therapy for CCM in resource-limited settings with risk highest during the first 6 months. Maintenance of patient follow up during this period may reduce mortality.

Introduction:Using the data of a trial on cotrimoxazole (CTX) cessation, we investigated the effect of different antiretroviral therapy (ART) regimens on the incidence of clinical malaria.Methods:During the cotrimoxazole cessation trial (ISRCTN44723643), HIV-infected Ugandan adults with CD4+ at least 250 cells/μl were randomized to receive either CTX prophylaxis or placebo and were followed for a median of 2.5 years. Blood slides for malaria microscopy were examined at scheduled visits and at unscheduled visits when the participant felt unwell. CD4+ cell counts were done 6-monthly. Malaria was defined as fever with a positive blood slide. ART regimens were categorized as nucleoside reverse transcriptase inhibitor (NRTI) only, non-nucleoside reverse transcriptase inhibitor (NNRTI)-containing or protease inhibitor containing. Malaria incidence was calculated using random effects Poisson regression to account for clustering of events.Results:Malaria incidence in the three ART regimen groups was 9.9 (3.6-27.4), 9.3 (8.3-10.4), and 3.5 (1.6-7.6) per 100 person-years, respectively. Incidence on protease inhibitors was lower than that on the other regimens with the results just reaching significance (adjusted rate ratio 0.4, 95% confidence interval = 0.2–1.0, comparing with NNRTI regimens). Stratification by CTX/placebo use gave similar results, without evidence of an interaction between the effects of CTX/placebo use and ART regimen. There was no evidence of an interaction between ART regimen and CD4+ cell count.Conclusion:There was some evidence that protease inhibitor-containing ART regimens may be associated with a lower clinical malaria incidence compared with other regimens. This effect was not modified by CTX use or CD4+ cell count. The antimalarial properties of protease inhibitors may have clinical and public health importance.

BackgroundCotrimoxazole (CTX) preventive therapy (CPT) reduces opportunistic infections and malaria in HIV-infected patients. In Africa, policies on sustained CPT during antiretroviral therapy (ART) differ between countries. We assessed the safety of discontinuing CPT in stable patients on ART in Uganda.MethodsCOSTOP was a double-blind placebo-controlled trial. Patients aged ≥18 years, on CPT, and stable on ART (CD4 counts ≥250 cells/μL); were randomised to daily oral placebo (PLC group) or cotrimoxazole 960 mg/tablet (CTX group). Co-primary outcomes were: (i) time to first cotrimoxazole-preventable infection, with non- inferiority of PLC defined as the upper one-sided 95% confidence limit of the adjusted hazard ratio(aHR) ≤1.25; and (ii) time to first grade 3/4 haematological adverse event.Findings2180 subjects (1091 PLC; 1089 CTX) were enrolled. 932 PLC and 943 CTX completed the trial after 12 months minimum follow up. Ninety-eight participants (59 PLC; 39 CTX) experienced 120 cotrimoxazole- preventable events, mainly bacterial pneumonia (72 events, 4 deaths PLC); (48 events, 2 deaths CTX). The aHR for time to first event was 1.57 (upper one-sided 95% confidence limit 2.21) in per protocol population (similar results in ITT population). 551 participants (318 CTX; 233 PLC) experienced 1043 haematological adverse events (616 CTX; 427 PLC). Time to the first adverse event, mainly neutropenia, was shorter in the CTX group (aHR 0.70 95%CI 0.59–0.82; log-rank χ2 = 18.08; P<0.0001). 362 (276 PLC, 86 CTX) participants experienced at least one episode of confirmed clinical malaria (P<0.0001).InterpretationIn ART stable patients with CD4 counts ≥250 cells/μL, continued CPT significantly reduces risk of severe bacterial infections and protects against malaria, while discontinuing CPT reduces haematological adverse events.