Efficacy and Safety of NVX-CoV2373 in Adults in the United States and Mexico.

BACKGROUND: NVX-CoV2373 is an adjuvanted, recombinant spike protein nanoparticle vaccine that was shown to have clinical efficacy for the prevention of coronavirus disease 2019 (Covid-19) in phase 2b-3 trials in the United Kingdom and South Africa, but its efficacy had not yet been tested in North America. METHODS: We conducted a phase 3, randomized, observer-blinded, placebo-controlled trial in the United States and Mexico during the first half of 2021 to evaluate the efficacy and safety of NVX-CoV2373 in adults (≥18 years of age) who had not had severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Participants were randomly assigned in a 2:1 ratio to receive two doses of NVX-CoV2373 or placebo 21 days apart. The primary objective was to determine vaccine efficacy against reverse-transcriptase-polymerase-chain-reaction-confirmed Covid-19 occurring at least 7 days after the second dose. Vaccine efficacy against moderate-to-severe disease and against different variants was also assessed. RESULTS: Of the 29,949 participants who underwent randomization between December 27, 2020, and February 18, 2021, a total of 29,582 (median age, 47 years; 12.6% ≥65 years of age) received at least one dose: 19,714 received vaccine and 9868 placebo. Over a period of 3 months, 77 cases of Covid-19 were noted - 14 among vaccine recipients and 63 among placebo recipients (vaccine efficacy, 90.4%; 95% confidence interval [CI], 82.9 to 94.6; P<0.001). Ten moderate and 4 severe cases occurred, all in placebo recipients, yielding vaccine efficacy against moderate-to-severe disease of 100% (95% CI, 87.0 to 100). Most sequenced viral genomes (48 of 61, 79%) were variants of concern or interest - largely B.1.1.7 (alpha) (31 of the 35 genomes for variants of concern, 89%). Vaccine efficacy against any variant of concern or interest was 92.6% (95% CI, 83.6 to 96.7). Reactogenicity was mostly mild to moderate and transient but was more frequent among NVX-CoV2373 recipients than among placebo recipients and was more frequent after the second dose than after the first dose. CONCLUSIONS: NVX-CoV2373 was safe and effective for the prevention of Covid-19. Most breakthrough cases were caused by contemporary variant strains. (Funded by Novavax and others; PREVENT-19 ClinicalTrials.gov number, NCT04611802.).

Evolution of HIV-1 envelope towards reduced neutralization sensitivity, as demonstrated by contemporary HIV-1 subtype B from the United States.

Subtype B HIV-1 has been the primary driver of the HIV-1 epidemic in the United States (U.S.) for over forty years and is also a prominent subtype in the Americas, Europe, Australia, the Middle East and North Africa. In this study, the neutralization profiles of contemporary subtype B Envs from the U.S. were assessed to characterize changes in neutralization sensitivities over time. We generated a panel of 30 contemporary pseudoviruses (PSVs) and demonstrated continued diversification of subtype B Env from the 1980s up to 2018. Neutralization sensitivities of the contemporary subtype B PSVs were characterized using 31 neutralizing antibodies (NAbs) and were compared with strains from earlier in the HIV-1 pandemic. A significant reduction in Env neutralization sensitivity was observed for 27 out of 31 NAbs for the contemporary as compared to earlier-decade subtype B PSVs. A decline in neutralization sensitivity was observed across all Env domains; the NAbs that were most potent early in the pandemic suffered the greatest decline in potency over time. A meta-analysis demonstrated this trend across multiple subtypes. As HIV-1 Env diversification continues, changes in Env antigenicity and neutralization sensitivity should continue to be evaluated to inform the development of improved vaccine and antibody products to prevent and treat HIV-1.

Genetic variation that determines TAPBP expression levels associates with the course of malaria in an HLA allotype-dependent manner.

HLA class I (HLA-I) allotypes vary widely in their dependence on tapasin (TAPBP), an integral component of the peptide-loading complex, to present peptides on the cell surface. We identified two single-nucleotide polymorphisms that regulate TAPBP messenger RNA (mRNA) expression in Africans, rs111686073 (G/C) and rs59097151 (A/G), located in an AP-2α transcription factor binding site and a microRNA (miR)-4486 binding site, respectively. rs111686073G and rs59097151A induced significantly higher TAPBP mRNA expression relative to the alternative alleles due to higher affinity for AP-2α and abrogation of miR-4486 binding, respectively. These variants associated with lower Plasmodium falciparum parasite prevalence and lower incidence of clinical malaria specifically among individuals carrying tapasin-dependent HLA-I allotypes, presumably by augmenting peptide loading, whereas tapasin-independent allotypes associated with relative protection, regardless of imputed TAPBP mRNA expression levels. Thus, an attenuated course of malaria may occur through enhanced breadth and/or magnitude of antigen presentation, an important consideration when evaluating vaccine efficacy.

Safety and Immunogenicity of Accelerated Heterologous Two-dose Ebola Vaccine Regimens in Adults With and Without HIV in Africa.

BACKGROUND: Shorter prophylactic vaccine schedules may offer more rapid protection against Ebola in resource-limited settings. METHODS: This randomized, observer-blind, placebo-controlled, phase 2 trial conducted in five sub-Saharan African countries included people without HIV (PWOH, n = 249) and people living with HIV (PLWH, n = 250). Adult participants received one of two accelerated Ebola vaccine regimens (MVA-BN-Filo, Ad26.ZEBOV administered 14 days apart [n = 79] or Ad26.ZEBOV, MVA-BN-Filo administered 28 days apart [n = 322]) or saline/placebo (n = 98). The primary endpoints were safety (adverse events [AEs]) and immunogenicity (Ebola virus [EBOV] glycoprotein-specific binding antibody responses). Binding antibody responders were defined as participants with a > 2.5-fold increase from baseline or the lower limit of quantification if negative at baseline. RESULTS: The mean age was 33.4 years, 52% of participants were female, and among PLWH, the median (interquartile range) CD4+ cell count was 560.0 (418.0-752.0) cells/µL. AEs were generally mild/moderate with no vaccine-related serious AEs or remarkable safety profile differences by HIV status. At 21 days post-dose 2, EBOV glycoprotein-specific binding antibody response rates in vaccine recipients were 99% for the 14-day regimen (geometric mean concentrations [GMCs]: 5168 enzyme-linked immunosorbent assay units (EU)/mL in PWOH; 2509 EU/mL in PLWH), and 98% for the 28-day regimen (GMCs: 6037 EU/mL in PWOH; 2939 EU/mL in PLWH). At 12 months post-dose 2, GMCs in PWOH and PLWH were 635 and 514 EU/mL, respectively, for the 14-day regimen and 331 and 360 EU/mL, respectively, for the 28-day regimen. CONCLUSIONS: Accelerated 14- and 28-day Ebola vaccine regimens were safe and immunogenic in PWOH and PLWH in Africa. TRIAL REGISTRATION: NCT02598388.

Safety, tolerability, and immunogenicity of the chimpanzee adenovirus type 3-vectored Marburg virus (cAd3-Marburg) vaccine in healthy adults in the USA: a first-in-human, phase 1, open-label, dose-escalation trial.

BACKGROUND: WHO has identified Marburg virus as an emerging virus requiring urgent vaccine research and development, particularly due to its recent emergence in Ghana. We report results from a first-in-human clinical trial evaluating a replication-deficient recombinant chimpanzee adenovirus type 3 (cAd3)-vectored vaccine encoding a wild-type Marburg virus Angola glycoprotein (cAd3-Marburg) in healthy adults. METHODS: We did a first-in-human, phase 1, open-label, dose-escalation trial of the cAd3-Marburg vaccine at the Walter Reed Army Institute of Research Clinical Trials Center in the USA. Healthy adults aged 18-50 years were assigned to receive a single intramuscular dose of cAd3-Marburg vaccine at either 1 × 1010 or 1 × 1011 particle units (pu). Primary safety endpoints included reactogenicity assessed for the first 7 days and all adverse events assessed for 28 days after vaccination. Secondary immunogenicity endpoints were assessment of binding antibody responses and T-cell responses against the Marburg virus glycoprotein insert, and assessment of neutralising antibody responses against the cAd3 vector 4 weeks after vaccination. This study is registered with ClinicalTrials.gov, NCT03475056. FINDINGS: Between Oct 9, 2018, and Jan 31, 2019, 40 healthy adults were enrolled and assigned to receive a single intramuscular dose of cAd3-Marburg vaccine at either 1 × 1010 pu (n=20) or 1 × 1011 pu (n=20). The cAd3-Marburg vaccine was safe, well tolerated, and immunogenic. All enrolled participants received cAd3-Marburg vaccine, with 37 (93%) participants completing follow-up visits; two (5%) participants moved from the area and one (3%) was lost to follow-up. No serious adverse events related to vaccination occurred. Mild to moderate reactogenicity was observed after vaccination, with symptoms of injection site pain and tenderness (27 [68%] of 40 participants), malaise (18 [45%] of 40 participants), headache (17 [43%] of 40 participants), and myalgia (14 [35%] of 40 participants) most commonly reported. Glycoprotein-specific antibodies were induced in 38 (95%) of 40 participants 4 weeks after vaccination, with geometric mean titres of 421 [95% CI 209-846] in the 1 × 1010 pu group and 545 [276-1078] in the 1 × 1011 pu group, and remained significantly elevated at 48 weeks compared with baseline titres (39 [95% CI 13-119] in the 1 ×1010 pu group and 27 [95-156] in the 1 ×1011 pu group; both p<0·0001). T-cell responses to the glycoprotein insert and neutralising responses against the cAd3 vector were also increased at 4 weeks after vaccination. INTERPRETATION: This first-in-human trial of this cAd3-Marburg vaccine showed the agent is safe and immunogenic, with a safety profile similar to previously tested cAd3-vectored filovirus vaccines. 95% of participants produced a glycoprotein-specific antibody response at 4 weeks after a single vaccination, which remained in 70% of participants at 48 weeks. These findings represent a crucial step in the development of a vaccine for emergency deployment against a re-emerging pathogen that has recently expanded its reach to new regions. FUNDING: National Institutes of Health.

Evolution of Antibody Responses in HIV-1 CRF01_AE Acute Infection: Founder Envelope V1V2 Impacts the Timing and Magnitude of Autologous Neutralizing Antibodies.

Understanding the dynamics of early immune responses to HIV-1 infection, including the evolution of initial neutralizing and antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies, will inform HIV vaccine design. In this study, we assess the development of autologous neutralizing antibodies (ANAbs) against founder envelopes (Envs) from 18 participants with HIV-1 CRF01_AE acute infection. The timing of ANAb development directly associated with the magnitude of the longitudinal ANAb response. Participants that developed ANAbs within 6 months of infection had significantly higher ANAb responses at 1 year (50% inhibitory concentration [IC50] geometric mean titer [GMT] = 2,010 versus 184; P = 0.001) and 2 years (GMT = 3,479 versus 340; P = 0.015), compared to participants that developed ANAb responses after 6 months. Participants with later development of ANAb tended to develop an earlier, potent heterologous tier 1 (92TH023) neutralizing antibody (NAb) response (P = 0.049). CRF01_AE founder Env V1V2 loop lengths correlated indirectly with the timing (P = 0.002, r = -0.675) and directly with magnitude (P = 0.005, r = 0.635) of ANAb responses; Envs with longer V1V2 loop lengths elicited earlier and more potent ANAb responses. While ANAb responses did not associate with viral load, the viral load set point correlated directly with neutralization of the heterologous 92TH023 strain (P = 0.007, r = 0.638). In contrast, a striking inverse correlation was observed between viral load set point and peak ADCC against heterologous 92TH023 Env strain (P = 0.0005, r = -0.738). These data indicate that specific antibody functions can be differentially related to viral load set point and may affect HIV-1 pathogenesis. Exploiting Env properties, such as V1V2 length, could facilitate development of subtype-specific vaccines that elicit more effective immune responses and improved protection. IMPORTANCE Development of an effective HIV-1 vaccine will be facilitated by better understanding the dynamics between the founder virus and the early humoral responses. Variations between subtypes may influence the evolution of immune responses and should be considered as we strive to understand these dynamics. In this study, autologous founder envelope neutralization and heterologous functional humoral responses were evaluated after acute infection by HIV-1 CRF01_AE, a subtype that has not been thoroughly characterized. The evolution of these humoral responses was assessed in relation to envelope characteristics, magnitude of elicited immune responses, and viral load. Understanding immune parameters in natural infection will improve our understanding of protective responses and aid in the development of immunogens that elicit protective functional antibodies. Advancing our knowledge of correlates of positive clinical outcomes should lead to the design of more efficacious vaccines.

HIV-1 infections with multiple founders associate with the development of neutralization breadth.

Eliciting broadly neutralizing antibodies (bnAbs) is a cornerstone of HIV-1 vaccine strategies. Comparing HIV-1 envelope (env) sequences from the first weeks of infection to the breadth of antibody responses observed several years after infection can help define viral features critical to vaccine design. We investigated the relationship between HIV-1 env genetics and the development of neutralization breadth in 70 individuals enrolled in a prospective acute HIV-1 cohort. Half of the individuals who developed bnAbs were infected with multiple HIV-1 founder variants, whereas all individuals with limited neutralization breadth had been infected with single HIV-1 founders. Accordingly, at HIV-1 diagnosis, env diversity was significantly higher in participants who later developed bnAbs compared to those with limited breadth (p = 0.012). This association between founder multiplicity and the subsequent development of neutralization breadth was also observed in 56 placebo recipients in the RV144 vaccine efficacy trial. In addition, we found no evidence that neutralization breath was heritable when analyzing env sequences from the 126 participants. These results demonstrate that the presence of slightly different HIV-1 variants in acute infection could promote the induction of bnAbs, suggesting a novel vaccine strategy, whereby an initial immunization with a cocktail of minimally distant antigens would be able to initiate bnAb development towards breadth.

Prevalence of Urogenital Mycoplasma genitalium Infection at 2 US Army Medical Facilities.

BACKGROUND: Sexually transmitted infections (STIs) have a high incidence in the US Armed Forces and can adversely impact service members' ability to perform their duties. Better knowledge of Mycoplasma genitalium (MG) epidemiology in the military is needed to understand the potential impact of this emerging pathogen on force readiness. METHODS: We conducted cross-sectional analyses of data from US Army service members and other Military Health System beneficiaries participating in a trial of an STI/HIV behavioral intervention at Fort Liberty, NC, and Joint Base Lewis-McChord, WA. At enrollment, participants completed questionnaires and provided biological specimens for nucleic acid amplification testing for MG, Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (NG). We used principal component analysis and robust Poisson regression to examine associations between participant characteristics and prevalent urogenital MG. RESULTS: Among 432 participants enrolled between November 2020 and February 2023, 43 had MG (prevalence, 10.0%), of whom 13 had coinfection with another bacterial STI (all 13 were positive for CT, with 1 also positive for NG). The prevalence of MG was significantly higher among female (13.5%) versus male (7.6%; P = 0.048) participants and non-Hispanic Black (14.9%) versus non-Hispanic White participants (6.6%; P = 0.045). Single relationship status and increased number of recent sexual partners were correlated, and their component was associated with higher MG prevalence (adjusted prevalence ratio, 2.11; 95% confidence interval, 1.29-3.48). CONCLUSIONS: The high prevalence of urogenital MG among Military Health System beneficiaries highlights the importance of understanding the potential clinical sequelae of MG and conducting additional epidemiologic research in military settings.

Differences in neutralizing antibody sensitivities and envelope characteristics indicate distinct antigenic properties of Nigerian HIV-1 subtype G and CRF02_AG.

The magnitude of the HIV-1 epidemic in Nigeria is second only to the subtype C epidemic in South Africa, yet the subtypes prevalent in Nigeria require further characterization. A panel of 50 subtype G and 18 CRF02_AG Nigerian HIV-1 pseudoviruses (PSV) was developed and envelope coreceptor usage, neutralization sensitivity and cross-clade reactivity were characterized. These PSV were neutralized by some antibodies targeting major neutralizing determinants, but potentially important differences were observed in specific sensitivities (eg. to sCD4, MPER and V2/V3 monoclonal antibodies), as well as in properties such as variable loop lengths, number of potential N-linked glycans and charge, demonstrating distinct antigenic characteristics of CRF02_AG and subtype G. There was preferential neutralization of the matched CRF/subtype when PSV from subtype G or CRF02_AG were tested using pooled plasma. These novel Nigerian PSV will be useful to study HIV-1 CRF- or subtype-specific humoral immune responses for subtype G and CRF02_AG.

Impact of weight gain with dolutegravir on antiretroviral adherence and viral suppression in four African countries.

OBJECTIVE: We hypothesized that total body weight (TBW) gain after switching antiretroviral therapy (ART) regimen to tenofovir disoproxil fumarate/lamivudine/dolutegravir (TLD) may negatively impact ART adherence and viral load (VL) and therefore sought to examine these associations. METHODS: The ongoing African Cohort Study (AFRICOS) enrols people with HIV at 12 facilities in Kenya, Nigeria, Tanzania and Uganda supported by The US President's Emergency Plan for AIDS Relief. Among ART-experienced participants who switched to TLD, we used multivariable multinomial logistic regression to examine associations between pre-/post-TLD changes in percentage TBW (≥5% gain, <5% change, ≥5% loss) and changes in self-reported ART adherence (0, 1-2, ≥3 days missed doses in past 30 days) and VL [(<50 copies/mL (undetectable), 50-999 copies/mL (detectable, but suppressed), ≥1000 copies/mL (unsuppressed)]. RESULTS: Among 1508 participants, median time from starting TLD to follow-up was 9 months (interquartile range: 7-11). Overall, 438 (29.1%) participants experienced a TBW gain ≥5%, which was more common among females than among males (32.2% vs 25.2%, p = 0.005) and participants switching from efavirenz [32.0% vs nevirapine (19.9%) and boosted protease inhibitor (20.0%); p < 0.001]. Compared with a TBW change <5% [950 (63.0%) participants], TBW gain ≥5% was not significantly associated with more days with missed ART doses [adjusted odds ratio (aOR) = 0.77, 95% confidence interval (CI): 0.48-1.23] or VL becoming detectable and/or unsuppressed (aOR = 0.69, 95% CI: 0.41-1.16). CONCLUSIONS: Although a substantial proportion of participants experienced weight gain after switching to TLD, we did not identify a significant impact on adherence or virological outcomes.

Perinatal Depressive Symptoms and Viral Non-suppression Among a Prospective Cohort of Pregnant Women Living with HIV in Nigeria, Kenya, Uganda, and Tanzania.

Depression is common during pregnancy and is associated with reduced adherence to HIV-related care, though little is known about perinatal trajectories of depression and viral suppression among women living with HIV (WLHV) in sub-Saharan Africa. We sought to assess any association between perinatal depressive symptoms and viral non-suppression among WLWH. Depressive symptomatology and viral load data were collected every 6 months from WLWH enrolled in the African Cohort Study (AFRICOS; January 2013-February 2020). Generalized estimating equations modeled associations between depressive symptoms [Center for Epidemiological Studies Depression (CES-D) ≥ 16] and viral non-suppression. Of 1722 WLWH, 248 (14.4%) had at least one pregnancy (291 total) and for 61 pregnancies (21.0%), women reported depressive symptoms (13.4% pre-conception, 7.6% pregnancy, 5.5% one-year postpartum). Depressive symptomatology was associated with increased odds of viral non-suppression (aOR 2.2; 95% CI 1.2-4.0, p = 0.011). Identification and treatment of depression among women with HIV may improve HIV outcomes for mothers.

Susceptibility to Human Immunodeficiency Virus Type 1 Acquisition Linked to Malaria Exposure: A Case-Control Study.

Human immunodeficiency virus (HIV) and malaria infection rates overlap across sub-Saharan Africa, but factors influencing their co-occurrence are unclear. In a case-control study, we investigated whether malaria exposure increases risk of type 1 (HIV-1) acquisition. Prior to seroconverting, HIV-positive cases had significantly higher malaria-associated antibodies compared to HIV-negative controls, linking malaria exposure to HIV-1 acquisition.

Transitioning women to first-line preferred TLD regimen is lagging in Sub-Saharan Africa.

INTRODUCTION: In 2019, the World Health Organization (WHO) recommended tenofovir disoproxil fumarate-lamivudine-dolutegravir (TLD) as the preferred first line regimen for adults and adolescents regardless of childbearing status. Nevertheless, final eligibility is determined by local policies which may vary from WHO recommendations. We examined TLD transition by gender across five PEPFAR-supported HIV care programs in sub-Saharan Africa. METHODS: The African Cohort Study (AFRICOS) enrolls people living with HIV (PLWH) engaged in care in Uganda, Kenya (South Rift Valley and Kisumu West), Tanzania and Nigeria. PLWH with at least one study visit after the country introduced TLD were included. We generated Kaplan-Meier (KM) curves to compare TLD transition by gender from 1) time countries' introduction of TLD and 2) time of TLD eligibility according to local policies. RESULTS: Among 2.476 participants enrolled through September 2021 at 4 sites in sub-Saharan Africa and eligible to transition to TLD, fewer women (68%) compared to men (80%, p < 0.001) were taking TLD. Kaplan-Meier analysis showed time to transition varied by site, with women in Tanzania transitioning at the same rate as men. In Nigeria, women initially had a slower transition but caught up to men. After adjusting for local policies, women[1] in Kisumu West transitioned at the same rate as men. In South Rift Valley and Uganda, women were less likely to be transitioned. CONCLUSIONS: Despite TLD being the WHO's preferred regimen since 2019, transition of women to potentially lifesaving TLD has been slower than men at certain clinical sites even after accounting for local eligibility criteria.

Predictors of All-Cause Mortality Among People With Human Immunodeficiency Virus (HIV) in a Prospective Cohort Study in East Africa and Nigeria.

BACKGROUND: Introduction of antiretroviral therapy (ART) has been associated with a decline in human immunodeficiency virus (HIV)-related mortality, although HIV remains a leading cause of death in sub-Saharan Africa. We describe all-cause mortality and its predictors in people living with HIV (PLWH) in the African Cohort Study (AFRICOS). METHODS: AFRICOS enrolls participants with or without HIV at 12 sites in Kenya, Uganda, Tanzania, and Nigeria. Evaluations every 6 months include sociobehavioral questionnaires, medical history, physical examination, and laboratory tests. Mortality data are collected from medical records and survivor interviews. Multivariable Cox proportional hazards models were used to calculate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for factors associated with mortality. RESULTS: From 2013 through 2020, 2724 PLWH completed at least 1 follow-up visit or experienced death. Of these 58.4% were females, 25.8% were aged ≥ 50 years, and 98.3% were ART-experienced. We observed 11.42 deaths per 1000 person-years (95% CI: 9.53-13.68) with causes ascertained in 54% of participants. Deaths were caused by malignancy (28.1%), infections (29.7%), and other non-HIV related conditions. Predictors of mortality included CD4 ≤ 350 cells/µL (aHR 2.01 [95% CI: 1.31-3.08]), a log10copies/mL increase of viral load (aHR 1.36 [95% CI: 1.22-1.51]), recent fever (aHR 1.85[95% CI: 1.22-2.81]), body mass index < 18.5 kg/m2 (aHR 2.20 [95% CI: 1.44-3.38]), clinical depression (aHR 2.42 [95% CI: 1.40-4.18]), World Health Organization (WHO) stage III (aHR 2.18 [95% CI: 1.31-3.61]), a g/dL increase in hemoglobin (aHR 0.79 [95% CI: .72-.85]), and every year on ART (aHR 0.67 [95% CI: .56-.81]). CONCLUSIONS: The mortality rate was low in this cohort of mostly virally suppressed PLWH. Patterns of deaths and identified predictors suggest multiple targets for interventions to reduce mortality.

Coronavirus Antibody Responses before COVID-19 Pandemic, Africa and Thailand.

Prior immune responses to coronaviruses might affect human SARS-CoV-2 response. We screened 2,565 serum and plasma samples collected from 2013 through early 2020, before the COVID-19 pandemic began, from 2,250 persons in 4 countries in Africa (Kenya, Nigeria, Tanzania, and Uganda) and in Thailand, including persons living with HIV-1. We detected IgG responses to SARS-CoV-2 spike (S) subunit 2 protein in 1.8% of participants. Profiling against 23 coronavirus antigens revealed that responses to S, subunit 2, or subunit 1 proteins were significantly more frequent than responses to the receptor-binding domain, S-Trimer, or nucleocapsid proteins (p<0.0001). We observed similar responses in persons with or without HIV-1. Among all coronavirus antigens tested, SARS-CoV-2, SARS-CoV-1, and Middle East respiratory syndrome coronavirus antibody responses were much higher in participants from Africa than in participants from Thailand (p<0.01). We noted less pronounced differences for endemic coronaviruses. Serosurveys could affect vaccine and monoclonal antibody distribution across global populations.

Limited Evidence for a Relationship between HIV-1 Glycan Shield Features in Early Infection and the Development of Neutralization Breadth.

Identifying whether viral features present in acute HIV-1 infection predetermine the development of neutralization breadth is critical to vaccine design. Incorporating such features in vaccine antigens could initiate cross-reactive antibody responses that could sufficiently protect vaccinees from HIV-1 infection despite the uniqueness of each founder virus. To understand the relationship between Env determinants and the development of neutralization breadth, we focused on 197 individuals enrolled in two cohorts in Thailand and East Africa (RV144 and RV217) and followed since their diagnosis in acute or early HIV-1 infection. We analyzed the distribution of variable loop lengths and glycans, as well as the predicted density of the glycan shield, and compared these envelope features to the neutralization breadth data obtained 3 years after infection (n = 121). Our study revealed limited evidence for glycan shield features that associate with the development of neutralization breadth. While the glycan shield tended to be denser in participants who subsequently developed breadth, no significant relationship was found between the size of glycan holes and the development of neutralization breadth. The parallel analysis of 3,000 independent Env sequences showed no evidence of directional evolution of glycan shield features since the beginning of the epidemic. Together, our results highlight that glycan shield features in acute and early HIV-1 infection may not play a role determinant enough to dictate the development of neutralization breadth and instead suggest that the glycan shield's reactive properties that are associated with immune evasion may have a greater impact. IMPORTANCE A major goal of HIV-1 vaccine research is to design vaccine candidates that elicit potent broadly neutralizing antibodies (bNAbs). Different viral features have been associated with the development of bNAbs, including the glycan shield on the surface of the HIV-1 Envelope (Env). Here, we analyzed data from two cohorts of individuals who were followed from early infection to several years after infection spanning multiple HIV-1 subtypes. We compared Env glycan features in HIV-1 sequences obtained in early infection to the potency and breadth of neutralizing antibodies measured 1 to 3 years after infection. We found limited evidence of glycan shield properties that associate with the development of neutralization breadth in these cohorts. These results may have important implications for antigen design in future vaccine strategies and emphasize that HIV-1 vaccines will need to rely on a complex set of properties to elicit neutralization breadth.

Individual Differences in CD4/CD8 T-Cell Ratio Trajectories and Associated Risk Profiles Modeled From Acute HIV Infection.

OBJECTIVE: We examined individual differences in CD4/CD8 T-cell ratio trajectories and associated risk profiles from acute HIV infection (AHI) through 144 weeks of antiretroviral therapy (ART) using a data-driven approach. METHODS: A total of 483 AHI participants began ART during Fiebig I-V and completed follow-up evaluations for 144 weeks. CD4+, CD8+, and CD4/CD8 T-cell ratio trajectories were defined followed by analyses to identify associated risk variables. RESULTS: Participants had a median viral load (VL) of 5.88 copies/ml and CD4/CD8 T-cell ratio of 0.71 at enrollment. After 144 weeks of ART, the median CD4/CD8 T-cell ratio was 1.3. Longitudinal models revealed five CD4/CD8 T-cell ratio subgroups: group 1 (3%) exhibited a ratio >1.0 at all visits; groups 2 (18%) and 3 (29%) exhibited inversion at enrollment, with normalization 4 and 12 weeks after ART, respectively; and groups 4 (31%) and 5 (18%) experienced CD4/CD8 T-cell ratio inversion due to slow CD4+ T-cell recovery (group 4) or high CD8+ T-cell count (group 5). Persistent inversion corresponded to ART onset after Fiebig II, higher VL, soluble CD27 and TIM-3, and lower eosinophil count. Individuals with slow CD4+ T-cell recovery exhibited higher VL, lower white blood cell count, lower basophil percent, and treatment with standard ART, as well as worse mental health and cognition, compared with individuals with high CD8+ T-cell count. CONCLUSIONS: Early HIV disease dynamics predict unfavorable CD4/CD8 T-cell ratio outcomes after ART. CD4+ and CD8+ T-cell trajectories contribute to inversion risk and correspond to specific viral, immune, and psychological profiles during AHI. Adjunctive strategies to achieve immune normalization merit consideration.

HIV and SARS-CoV-2: Tracing a Path of Vaccine Research and Development.

PURPOSE OF REVIEW: This review examines the major advances and obstacles in the field of HIV vaccine research as they pertain to informing the development of vaccines against SARS-CoV-2. RECENT FINDINGS: Although the field of HIV research has yet to deliver a licensed vaccine, the technologies developed and knowledge gained in basic scientific disciplines, translational research, and community engagement have positively impacted the development of vaccines for other viruses, most notably and recently for SARS-CoV-2. These advances include the advent of viral vectors and mRNA as vaccine delivery platforms; the use of structural biology for immunogen design; an emergence of novel adjuvant formulations; a more sophisticated understanding of viral phylogenetics; improvements in the development and harmonization of accurate assays for vaccine immunogenicity; and maturation of the fields of bioethics and community engagement for clinical trials conducted in diverse populations. Decades of foundational research and investments into HIV biology, though yet to yield an authorized or approved vaccine for HIV/AIDS, have now paid dividends in the rapid development of safe and effective SARS-CoV-2 vaccines. This latter success presents an opportunity for feedback on improved pathways for development of safe and efficacious vaccines against HIV and other pathogens.

PEPFAR's Role in Protecting and Leveraging HIV Services in the COVID-19 Response in Africa.

PURPOSE OF REVIEW: We describe the impact of COVID-19 on PEPFAR programs in Africa and how PEPFAR adapted and leveraged its interventions to the changing landscape of the COVID-19 pandemic. RECENT FINDINGS: To mitigate the potential impact of COVID-19 on the HIV response and protect the gains, continuity of treatment was the guiding principle regarding the provision of services in PEPFAR-supported countries. As the COVID-19 pandemic matured, PEPFAR's approach evolved from a strictly "protect and salvage" approach to a "restore and accelerate" approach that embraced innovative adaptations in service and "person-centered" care. The impact of service delivery interruptions caused by COVID-19 on progress towards HIV epidemic control in PEPFAR-supported African countries remains undetermined. With COVID vaccine coverage many months away and more transmissible variants being reported, Africa may experience more pandemic surges. HIV programs will depend on nimble and innovative adaptations in prevention and treatment services in order to advance epidemic control objectives.

Temporal trends in self-reported HIV stigma and association with adherence and viral suppression in the African Cohort Study.

HIV stigma is a major barrier to HIV care and treatment among people living with HIV (PLWH). Evidence suggests that expansion in antiretroviral therapy (ART) may reduce stigma. However, there are limited longitudinal studies examining temporal trends in HIV stigma in sub-Saharan Africa in the Undetectable = Untransmittable (U = U) era. We longitudinally assessed temporal trends in self-reported experienced stigma and the association of experienced stigma with ART adherence and viral suppression among PLWH enrolled in the African Cohort Study (AFRICOS). AFRICOS is an ongoing cohort study enrolling PLWH in Uganda, Kenya, Tanzania, and Nigeria. As of 1 March 2020, 2937 PLWH enrolled in AFRICOS and had available data. In 2013, 22% of participants reported stigma at the enrollment visit and by 2018 the prevalence decreased to 1% overall and was below 2% for all countries. However, there was not a statistically significant change in stigma prevalence in our longitudinal models. In adjusted models, experiencing stigma was associated with a 0.67 decreased odds of ART Adherence (95% confidence interval (CI): 0.56-0.80) and a 0.64 decreased odds of viral suppression (95% CI: 0.73-0.99). HIV-associated stigma was associated with poor self-reported ART adherence and unsuppressed viral load.