Local intramuscular administration of synthetic plasmid DNA (pDNA) encoding monoclonal antibodies (mAbs) offers a promising alternative to traditional recombinant protein-based mAb delivery. This approach may enable durable in vivo expression of functional antibodies and overcome limitations related to cost, production, and cold-chain logistics. AZD5396 and AZD8076 are modified versions of the SARS-CoV-2 neutralizing antibody cocktail Evusheld, encoded as DNA-delivered monoclonal antibodies (DMAbs). CONSORT diagram and trial schematic Longitudinal serum concentration of in vivo-expressed DMAbs AZD5396 and AZD8076 In this Phase 1, dose-escalation study (ClinicalTrials.gov identifier: NCT05293249), we evaluated the safety, tolerability, and pharmacokinetics of a pDNA cocktail encoding AZD5396 and AZD8076 in healthy adults. Participants received up to four intramuscular doses of the pDNA cocktail delivered by CELLECTRA™ electroporation. The primary endpoints were safety and pharmacokinetics. Exploratory endpoints included anti-drug antibody (ADA) development and functional activity against SARS-CoV-2 variants. All 44 enrolled participants received at least one dose, and DMAbs were detected in 100% of evaluable participants (n=39). Serum DMAb concentrations reached a mean peak of 1.11 µg/mL, with sustained expression observed in all participants who completed 72 weeks of follow-up. The product was well tolerated, and no product-related serious adverse events were reported. Exploratory analyses demonstrated binding to multiple SARS-CoV-2 spike variants and neutralizing activity in pseudovirus assays. Across ∼1,000 serum samples, no ADAs were detected using validated tiered assays. These findings provide the first-in-human proof-of-concept that synthetic pDNA DMAb technology enables durable in vivo production of a functional mAb cocktail. The results highlight the critical role of optimized synthetic design, formulation, and delivery in achieving biologically relevant expression. DNA-delivered mAbs may represent a long-acting, scalable, cold-chain-independent platform for targeting a wide range of diseases treatable with antibody-based therapeutics. All Authors: No reported disclosures

Background: Doravirine and islatravir is an investigational, once-daily, single-tablet regimen containing two potent antiretrovirals with complementary mechanisms of action and resistance profiles. We aimed to evaluate the efficacy and safety of switching from stable, oral antiretroviral therapy (ART) to the fixed combination of doravirine (100 mg) and islatravir (025 mg) in virologically suppressed adults living with HIV-1. Methods: This phase 3, randomised, active-controlled, open-label, non-inferiority trial was conducted at 53 research, community, and hospital-based clinics in eight countries: Australia, Canada, Colombia, Japan, South Africa, Switzerland, the UK, and the USA. Adults (aged >= 18 years) with a viral load of fewer than 50 copies of HIV-1 RNA per mL on any oral, two-drug or three-drug ART regimen for at least 3 months, with no history of treatment failure, known resistance to doravirine, or active hepatitis B infection, were randomly assigned (2:1) according to a computer-generated randomisation schedule (block size three) to receive oral doravirine (100 mg) and islatravir (025 mg) once daily or to continue baseline ART for 48 weeks. Randomisation was stratified by the anchor antiretroviral drug class (integrase strand-transfer inhibitor [INSTI], non-nucleoside reverse transcriptase inhibitor, or protease inhibitor) in the baseline regimen. The primary endpoint (assessed in all treated participants) was the percentage of participants with a viral load of 50 copies per mL or higher at week 48 (analysed according to the US Food and Drug Administration snapshot approach); non-inferiority would be concluded if the upper bound of the multiplicity-adjusted 95% CI for the treatment difference was less than 4%. The safety analysis population included all randomly assigned participants who received at least one dose of study treatment. The trial is registered at ClinicalTrials.gov, NCT05631093, and is ongoing but closed to enrolment. Findings: Between Feb 20 and Oct 24, 2023, 614 individuals were screened for eligibility, of whom 553 were randomly assigned to receive doravirine and islatravir (n=368) or baseline ART (n=185). 551 participants received at least one dose of allocated medication: 366 in the doravirine and islatravir group and 185 in the baseline ART group. Of these 551 participants, 332 (60%) were assigned male and 219 (40%) were assigned female at birth, and the median age was 51 years (IQR 41-59); 250 (45%) identified as Black or African American and 80 (15%) identified as Hispanic, Latino, or Latina. Doravirine and islatravir showed non-inferiority at week 48, with viral loads of 50 copies per mL or higher in five (14%) of 366 participants versus nine (49%) of 185 participants on baseline ART (difference -36% [multiplicity-adjusted 95% CI -78 to -08]). Treatment-related adverse events were more common with doravirine and islatravir (44 [120%] of 366 participants) than with baseline ART (nine [49%] of 185 participants; difference 72 [95% CI 22 to 116]). Rates were similar in the doravirine and islatravir group and the baseline ART group for any adverse event (795% [291 of 366 participants] vs 838% [155 of 185 participants]; difference -43 [-107 to 28]), serious adverse events (63% [23] vs 49% [nine]; 14 [-32 to 52]), and discontinuation due to adverse events (05% [two] vs 22% [four]; -16 [-49 to 02]). One death occurred (in the baseline ART group) and was not considered treatment-related. No participants discontinued treatment as a result of protocol-specified declines in CD4 cell or total lymphocyte counts. Interpretation: Doravirine and islatravir is efficacious and well tolerated and would represent the first non-INSTI-based, two-drug regimen for HIV-1 treatment. With increasing concern over the potential development of widespread INSTI resistance, this once-daily, oral, single-tablet regimen could be a potential option for people living with HIV-1 requiring a change to their antiretroviral regimen. The safety and efficacy findings support the ongoing development of islatravir, a drug with long-acting potential.

Doravirine/islatravir (DOR/ISL, 100 mg/0.25 mg) is an investigational once-daily regimen for HIV treatment. In two Phase 3 studies, switching to DOR/ISL was non-inferior for efficacy with a safety profile comparable to continuing baseline antiretroviral therapy (bART) or bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) at Week 48 (W48). Because concerns about comorbidities and drug tolerability increase with age, this subgroup analysis evaluated the efficacy and safety of DOR/ISL by age. Adults with HIV-1 RNA < 50 copies/mL receiving stable oral bART (MK-8591A-051 [P051]; NCT05631093) or BIC/FTC/TAF (MK-8591A-052 [P052]; NCT05630755) for ≥3 months were randomized (2:1) to switch to DOR/ISL (100 mg/0.25 mg) or to continue bART (P051) or BIC/FTC/TAF (P052). For P051+P052, efficacy results were pooled for both the DOR/ISL arms and the comparator arms (pooled comparator) and were summarized by age (< 50, ≥50 years) through W48. AEs and weight were reported by age subgroup for each study. Across both studies, 708 participants switched to DOR/ISL and 356 continued bART or BIC/FTC/TAF (pooled comparator); overall 49.7% were ≥50 years old (10.6% ≥65 years). At W48, the proportion of DOR/ISL participants with HIV-1 RNA < 50 copies/mL was similar between those < 50 and ≥50 years in the pooled DOR/ISL group (92.1% vs 95.2%) and similar to the pooled comparator (94.5% vs 91.4%; Figure). Among DOR/ISL participants, rates of AEs, drug-related AEs, serious AEs, and discontinuations due to AEs were similar between age subgroups in both studies (Table). The AE profile was similar by treatment group for participants ≥65 years old. Rates of drug-related AEs were higher for open-label DOR/ISL than bART (P051), with a greater difference for participants ≥50 years, but were comparable between blinded treatment groups (P052). For DOR/ISL participants, weight changes were minimal overall (range of mean percent change in age subgroups −0.51% to 2.12%; Table). There were no clinically meaningful differences in weight change between those < 50 years and those ≥50 years. At W48, switching to DOR/ISL (100 mg/0.25 mg) demonstrated high efficacy and was generally well tolerated across age subgroups in adults living with HIV-1, including those ≥50 years. Pablo Tebas, MD, Merck: Honoraria|Shionogi: Honoraria|Viiv: Honoraria Frank A. Post, MD, PhD, Gilead: Grant/Research Support|Gilead: Honoraria|MSD: Grant/Research Support|MSD: Honoraria Moti Ramgopal, MD, FACP, FIDSA, AbbVie: Speaker Bureau|Gilead: Advisor/Consultant|Gilead: Honoraria|Shionogi Inc: Consultant|ViiV Healthcare: Advisor/Consultant|ViiV Healthcare: Honoraria Marcel Stoeckle, MD, Gilead: Advisor/Consultant|Gilead: Congress grants Andrew Carr, MD, Gilead: Board Member|Gilead: Grant/Research Support|Gilead: Honoraria|MSD: Board Member|MSD: Grant/Research Support|MSD: Honoraria|ViiV Healthcare: Board Member|ViiV Healthcare: Grant/Research Support|ViiV Healthcare: Honoraria Olayemi O. Osiyemi, MD, Gilead Sciences, Inc.: Advisor/Consultant|Gilead Sciences, Inc.: Honoraria|Merck: Advisor/Consultant|Merck: Honoraria|ViiV: Advisor/Consultant|ViiV: Honoraria Ronald G. Nahass, MD, Arbutus Pharma: Grant/Research Support|Insemed: Grant/Research Support|Janssen: Grant/Research Support|Merck: Grant/Research Support|VIR Pharma: Grant/Research Support Jason Szabo, MD, PhD, Gilead: Grant/Research Support|Gilead: Advisory board; Speaker fees|Merck: Speaker Fees|Novo Nordisk: Advisory board|ViiV: Grant/Research Support|ViiV: Advisory board; Speaker fees Anjana Grandhi, PhD, Merck & Co., Inc.: Employment|Merck & Co., Inc.: Stocks/Bonds (Public Company) Monica Fuszard, MS, Merck & Co.: Employment Stephanie O. Klopfer, PhD, Merck & Co., Inc: Employment|Merck & Co., Inc: Stocks/Bonds (Public Company) Rima Lahoulou, n/a, MSD: Employment|MSD: Stocks/Bonds (Private Company) Luisa M. Stamm, MD, PhD, Merck & Co., Inc.: Employment|Merck & Co., Inc.: Stocks/Bonds (Public Company) Michelle C. Fox, MD, Merck & Co., Inc.: Employment|Merck & Co., Inc.: Stocks/Bonds (Public Company) Jason Y. Kim, MD, MSCE, Merck & Co.: Employment|Merck & Co.: Stocks/Bonds (Public Company)

We conducted a first-in-human evaluation of HIV-specific, HIV-resistant chimeric antigen receptor (CAR) T cells (CARTs) to determine their capacity to modulate viral rebound dynamics following analytic treatment interruption (ATI). Among ten treated individuals who received engineered T cells, one individual did not rebound during the ATI and had a remarkable expansion of their CARTs 43 days after the start of the ATI, suggesting that the CARTs recognized rebounding HIV and prevented its spread. Post-rebound virologic control was observed in 1 participant for 90 weeks and another 5 participants had remarkable reductions in their viral load after viral peak was reached, maintaining viral loads below their set point. CART infusion was associated with broad reinvigoration of endogenous HIV-specific CD8 T cell responses, and immune escape to one of these responses was documented. Together, these findings show that HIV-specific CARTs can be an integral component in HIV Cure strategies.

This article provides a focused update to the clinical practice guideline on the treatment and management of people with COVID-19, developed by the Infectious Diseases Society of America. The guideline panel presents 9 updated recommendations on the use of nirmatrelvir/ritonavir, remdesivir, and molnupiravir, in adults with mild to moderate COVID-19. The recommendations are based on evidence derived from a systematic literature review and adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. The panel also provides a section on how to apply these recommendations, including an algorithm on the selection of antivirals.

This article provides a focused update to the clinical practice guideline on the treatment and management of patients with coronavirus disease 2019, developed by the Infectious Diseases Society of America. The guideline panel presents a recommendation on the use of the anti-severe acute respiratory syndrome coronavirus 2 neutralizing antibody pemivibart as pre-exposure prophylaxis. The recommendation is based on evidence derived from a systematic review and adheres to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach. Information on pemivibart is included in the U.S. Food and Drug Administration Emergency Use Authorization for this agent.

Intact HIV-1 proviruses become progressively enriched in transcriptionally repressive genomic regions during long-term antiretroviral therapy (ART) and in elite controllers, raising questions about their capacity for reactivation in vivo. We used an antigen-restricted quantitative viral outgrowth assay (ag qVOA) to test whether cognate antigen stimulation can reverse latency of proviruses integrated within repressive chromatin. Using cells from two people with HIV (PWH) on ART, one on long-term treatment and one an elite controller, we show that antigen-specific stimulation induces viral outgrowth from intact proviruses integrated into a pericentromeric transition region and a zinc finger gene, respectively. These findings demonstrate that antigen recognition can overcome epigenetic constraints to reactivate proviruses with low inducibility and suggest that proviruses in so-called "deeper latency" may contribute to residual viremia and viral rebound following treatment interruption.

Coupling the HIV fusion inhibitor C34 with CXCR4 (C34-CXCR4) protected CD4 T cells from all strains of HIV. Escape from C34-CXCR4 expression proved difficult, requiring more than 21 serial passages, mutations at conserved gp41 sites, and a complete loss of Vpu activity. A dose-escalation phase 1 clinical trial was performed in which up to 10 billion C34-CXCR4-expressing T cells were infused into people with HIV (PWH). While these infusions were safe, we observed limited persistence of these C34-CXCR4 T cells, lack of reconstitution of HIV-specific CD8 T cell responses, and no effect on time to viral rebound after an analytical treatment interruption. We hypothesized that inappropriate expression of a signaling-competent chemokine receptor resulted in the limited persistence of these engineered T cells, so we screened several C34-CXCR4 mutants to identify those that could not respond to CXCL12 and still could mediate potent antiviral activity. A single mutation (D97N) in CXCR4 fulfilled both criteria. T cells co-expressing dual HIV-specific chimeric antigen receptors (CARs) and C34-CXCR4 D97N maintained high C34 expression in vivo and controlled HIV replication better than unprotected dual CAR T cells, suggesting that this C34-CXCR4 D97N construct should be considered for future clinical development.

BACKGROUND:Doravirine and islatravir is an investigational, once-daily, single-tablet regimen containing two potent antiretrovirals with complementary mechanisms of action and resistance profiles. We aimed to evaluate the efficacy and safety of switching from stable, oral antiretroviral therapy (ART) to the fixed combination of doravirine (100 mg) and islatravir (0·25 mg) in virologically suppressed adults living with HIV-1. METHODS:This phase 3, randomised, active-controlled, open-label, non-inferiority trial was conducted at 53 research, community, and hospital-based clinics in eight countries: Australia, Canada, Colombia, Japan, South Africa, Switzerland, the UK, and the USA. Adults (aged ≥18 years) with a viral load of fewer than 50 copies of HIV-1 RNA per mL on any oral, two-drug or three-drug ART regimen for at least 3 months, with no history of treatment failure, known resistance to doravirine, or active hepatitis B infection, were randomly assigned (2:1) according to a computer-generated randomisation schedule (block size three) to receive oral doravirine (100 mg) and islatravir (0·25 mg) once daily or to continue baseline ART for 48 weeks. Randomisation was stratified by the anchor antiretroviral drug class (integrase strand-transfer inhibitor [INSTI], non-nucleoside reverse transcriptase inhibitor, or protease inhibitor) in the baseline regimen. The primary endpoint (assessed in all treated participants) was the percentage of participants with a viral load of 50 copies per mL or higher at week 48 (analysed according to the US Food and Drug Administration snapshot approach); non-inferiority would be concluded if the upper bound of the multiplicity-adjusted 95% CI for the treatment difference was less than 4%. The safety analysis population included all randomly assigned participants who received at least one dose of study treatment. The trial is registered at ClinicalTrials.gov, NCT05631093, and is ongoing but closed to enrolment. FINDINGS:Between Feb 20 and Oct 24, 2023, 614 individuals were screened for eligibility, of whom 553 were randomly assigned to receive doravirine and islatravir (n=368) or baseline ART (n=185). 551 participants received at least one dose of allocated medication: 366 in the doravirine and islatravir group and 185 in the baseline ART group. Of these 551 participants, 332 (60%) were assigned male and 219 (40%) were assigned female at birth, and the median age was 51 years (IQR 41-59); 250 (45%) identified as Black or African American and 80 (15%) identified as Hispanic, Latino, or Latina. Doravirine and islatravir showed non-inferiority at week 48, with viral loads of 50 copies per mL or higher in five (1·4%) of 366 participants versus nine (4·9%) of 185 participants on baseline ART (difference -3·6% [multiplicity-adjusted 95% CI -7·8 to -0·8]). Treatment-related adverse events were more common with doravirine and islatravir (44 [12·0%] of 366 participants) than with baseline ART (nine [4·9%] of 185 participants; difference 7·2 [95% CI 2·2 to 11·6]). Rates were similar in the doravirine and islatravir group and the baseline ART group for any adverse event (79·5% [291 of 366 participants] vs 83·8% [155 of 185 participants]; difference -4·3 [-10·7 to 2·8]), serious adverse events (6·3% [23] vs 4·9% [nine]; 1·4 [-3·2 to 5·2]), and discontinuation due to adverse events (0·5% [two] vs 2·2% [four]; -1·6 [-4·9 to 0·2]). One death occurred (in the baseline ART group) and was not considered treatment-related. No participants discontinued treatment as a result of protocol-specified declines in CD4 cell or total lymphocyte counts. INTERPRETATION:Doravirine and islatravir is efficacious and well tolerated and would represent the first non-INSTI-based, two-drug regimen for HIV-1 treatment. With increasing concern over the potential development of widespread INSTI resistance, this once-daily, oral, single-tablet regimen could be a potential option for people living with HIV-1 requiring a change to their antiretroviral regimen. The safety and efficacy findings support the ongoing development of islatravir, a drug with long-acting potential. FUNDING:Merck Sharp & Dohme, a subsidiary of Merck & Co.

This article provides a focused update to the clinical practice guideline on the treatment and management of patients with coronavirus disease 2019 (COVID-19), developed by the Infectious Diseases Society of America. The guideline panel presents a recommendation on the use of abatacept in hospitalized adults with severe or critical COVID-19. The recommendation is based on evidence derived from a systematic literature review and adheres to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach.

As the first part of several focused updates to the clinical practice guideline on the treatment and management of COVID-19 in adults, children, and pregnant people, developed by the Infectious Diseases Society of America, the panel presents four new recommendations. These recommendations include pre-exposure prophylaxis for immunocompromised persons and treatment of severe or critical COVID-19. The panel’s recommendations are based upon evidence derived from systematic literature reviews and adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach.

BACKGROUND:Long-acting regimens are needed to expand antiretroviral therapy (ART) options for people with human immunodeficiency virus type 1 (HIV-1). Combining broadly neutralizing antibodies (bNAbs) with long-acting small-molecule antiretrovirals may offer an alternative to daily oral therapy. METHODS:We conducted a phase 2, open-label, single-arm trial at AIDS Clinical Trials Group (ACTG) sites across the United States. Eligible adults had HIV-1 virologically suppressed on ART for ≥2 years, CD4 count ≥350 cells/μL, and susceptibility to VRC07-523LS (half-maximal inhibitory concentration ≤0.25 µg/mL; inhibition >98%). Participants completed an oral cabotegravir (CAB) lead-in (Step 1), then received intravenous VRC07-523LS (40 mg/kg every 8 weeks) plus intramuscular CAB-LA (every 4 weeks) for 48 weeks (Step 2), followed by a return to standard ART (Step 3). Primary outcomes were treatment-related grade ≥3 adverse events (AEs), treatment discontinuation, and confirmed HIV-1 RNA ≥200 copies/mL by week 44. Virologic efficacy was assessed using Kaplan-Meier estimates. RESULTS:Seventy-four participants were enrolled (median age, 54 years; 26% female; 51% non-Hispanic White). Twelve (17%) experienced a primary safety event: 11 (15%) had grade ≥3 AEs, primarily transient infusion reactions, and 1 discontinued due to a grade 1 infusion event. The cumulative probability of virologic failure by week 44 was 7% (95% confidence interval, 3%-16%). One participant developed the R263K integrase resistance mutation. CONCLUSIONS:The VRC07-523LS plus CAB-LA regimen maintained viral suppression in 93% of participants, with only transient infusion reactions observed; however, instances of virologic breakthrough suggest that future studies should focus on optimizing efficacy outcomes. These results support continued investigation of bNAb-based long-acting ART combinations.

Tissue-resident memory T cells (Trms) are essential for mucosal immunity. We postulated that their long-lived tissue residency and restricted effector function promoted HIV-1 persistence in the gut. We coupled single-cell DOGMA-seq and TREK-seq to capture chromatin accessibility, transcriptome, surface proteins, T cell receptors (TCRs), HIV-1 DNA, and HIV-1 RNA in gut CD4+ and CD8+ T cells from ten aviremic HIV-1+ individuals and five HIV- donors. BACH2, a transcriptional repressor that establishes long-lived memory in T cells, was a key transcription factor that shaped gut Trms into long-lived memory and restrained interferon-driven effector function. BACH2-ablation shifted long-lived central memory T cells to effector memory. HIV-1-infected cells were predominantly identified among BACH2high Trms, and HIV-1 preferentially infected and persisted in gut Trms in vitro. HIV-1-specific CD8+ T cells exhibited tissue residency and epigenetic scars of exhaustion, contributing to HIV-1 immune evasion in the gut. Overall, our findings indicate that HIV-1 persists in BACH2-shaped long-lived Trms.

BACKGROUNDAntiretroviral therapy (ART) prevents HIV-1 replication but does not eliminate the latent reservoir, the source of viral rebound if treatment is stopped. Autologous neutralizing antibodies (aNAbs) can block in vitro outgrowth of a subset of reservoir viruses and therefore potentially affect viral rebound upon ART interruption.METHODSWe investigated aNAbs in 31 people with HIV-1 (PWH) on ART.RESULTSParticipants fell into 2 groups based on a high or low fraction of aNAb-resistant reservoir isolates, with most isolates being aNAb-resistant (IC50 > 100 μg/mL). Time on uninterrupted ART was associated with higher aNAb resistance. However, pharmacodynamic analysis predicted that many isolates would be partially inhibited at physiologic IgG concentrations, to the same degree as by single antiretroviral drugs. Steep dose-response curve slopes, an indication of cooperativity, were observed for the rare isolates that were very strongly inhibited (> 5 logs) by aNAbs. Resistance to aNAbs was not fully explained by declining in aNAb titers and may be driven partially by ADCC-mediated elimination of infected cells carrying aNAb-sensitive viruses over long time intervals, leaving only aNAb-resistant viruses, which can contribute to viral rebound.CONCLUSIONInhibition of reservoir viruses by aNAbs may be affected by dose-response curve slope, time on uninterrupted ART, waning of antibody responses, and selection against cells with aNAb-sensitive viruses.FUNDINGThis work was supported by NIH Martin Delaney Collaboratories for HIV Cure Research grant awards UM1AI164556, UM1AI164570, and UM1AI164560, and the Howard Hughes Medical Institute.

Reactivation of the latent viral reservoirs is crucial for a cure of HIV/AIDS. However, current latency reversing agents are inefficient, and the endogenous factors that have the potential to reactivate HIV in vivo remain poorly understood. To identify natural activators of latent HIV-1, we screened a comprehensive peptide/protein library derived from human hemofiltrate, representing the entire blood peptidome, using J-Lat cell lines harboring transcriptionally silent HIV-1 GFP reporter viruses. Fractions potently reactivating HIV-1 from latency contained human Retinol Binding Protein 4 (RBP4), the carrier of retinol (Vitamin A). We found that retinol-bound holo-RBP4 but not retinol-free apo-RBP4 strongly reactivates HIV-1 in a variety of latently infected T cell lines. Functional analyses indicate that this reactivation involves activation of the canonical NF-κB pathway and is strengthened by JAK/STAT5 and JNK signalling but does not require retinoic acid production. High levels of RBP4 were detected in plasma from both healthy individuals and people living with HIV-1. Physiological concentrations of RBP4 induced significant viral reactivation in latently infected cells from individuals on long-term antiretroviral therapy with undetectable viral loads. As a potent natural HIV-1 latency-reversing agent, RBP4 offers a novel approach to activating the latent reservoirs and bringing us closer to a cure.

Long-term risks of gene therapy are not fully understood. In this study, we evaluated safety outcomes in 783 patients over more than 2,200 total patient-years of observation from 38 T cell therapy trials. The trials employed integrating gammaretroviral or lentiviral vectors to deliver engineered receptors to target HIV-1 infection or cancer. Eighteen patients (2.3

Local intramuscular administration of synthetic plasmid DNA (pDNA) encoding monoclonal antibodies (mAb) represents an alternative approach to recombinant protein technology. In this Phase 1, dose escalation study (NCT05293249), we administered a pDNA cocktail encoding AZD5396 and AZD8076, modified versions of the SARS-CoV-2 neutralizing mAb cocktail Evusheld™, by CELLECTRA™ in vivo electroporation technology to healthy adults. Primary endpoints of this study were safety and pharmacokinetics of the in vivo expressed DNA-encoded mAbs (DMAbs). Muscle-expressed DMAbs were detected in the serum of all dosed subjects (N=39), with concentrations reaching 1.39 µg/ml. Remarkably consistent levels of serum DMAbs were measured for at least 72 weeks post-administration in 24/24 subjects who have reached this time point. DMAbs isolated from serum demonstrated SARS-CoV-2 RBD binding and neutralization activity in a standard pseudovirus assay. While the study is ongoing, we have not detected anti-drug antibodies in any of the trial participants thus far. These data represent the first clinical proof-of-concept that synthetic pDNA DMAb technology permits the durable in vivo production of a functional mAb cocktail. This study further underscores the collective importance of synthetic design, formulation, and delivery to achieve biologically relevant expression of gene-encoded biologics. DMAb delivery may represent a valuable strategy against a wide range of diseases which can be targeted with mAbs and their derivatives.

Reactivation of the latent viral reservoirs is crucial for a cure of HIV/AIDS. However, current latency reversing agents are inefficient and the endogenous factors that have the potential to reactivate HIV in vivo remain poorly understood. To identify natural activators of latent HIV-1, we screened a comprehensive peptide/protein library derived from human hemofiltrate, representing the entire blood peptidome, using J-Lat cell lines harboring transcriptionally silent HIV-1 GFP reporter viruses. Fractions potently reactivating HIV-1 from latency contained human Retinol Binding Protein 4 (RBP4), the carrier of retinol (vitamin A). We found that retinol-bound holo-RBP4 but not retinol-free apo-RBP4 strongly reactivates HIV-1 in a variety of latently infected T cell lines. Functional analysis revealed that this reactivation depends on the JAK/STAT5 and JNK pathways but does not require retinoic acid production. High levels of RBP4 were detected in plasma from both healthy individuals and people living with HIV-1. Physiological concentrations of RBP4 induced significant viral reactivation in latently infected cells from individuals on long-term antiretroviral therapy with undetectable viral loads. As a potent natural HIV-1 latency-reversing agent, RBP4 offers a novel approach to activating the latent reservoirs and bringing us closer to a cure. ### Competing Interest Statement The authors have declared no competing interest.

BACKGROUND. HIV-1-specific broadly neutralizing monoclonal antibodies (bNAbs) have emerged as promising interventions with the potential to effectively treat and prevent HIV-1 infections. We conducted a phase I clinical trial evaluating the potent CD4-binding site-specific (CD4bs-specific) bNAbs VRC01LS and VRC07-523LS in people with HIV-1 (PWH) not receiving antiretroviral therapy (ART). METHODS. Participants received a single intravenous 40 mg/kg dose of either VRC01LS (n = 7) or VRC07-523LS (n = 9) and did not initiate ART for a minimum of 14 days. The primary study objective was to evaluate safety and tolerability; the secondary study objectives were to evaluate pharmacokinetics (PK) and the impact of administered bNAbs on viral loads (VL) and CD4(+) T cell counts in the absence of ART. RESULTS. This trial enrolled 16 PWH aged 20 to 57 years. Both bNAbs were safe and well tolerated. Mild local reactogenicity was only reported in participants who received VRC07-523LS, while both bNAbs were associated with mild systemic symptoms. Maximum serum concentrations (C-max) following VRC01LS or VRC07-523LS were 1,566 +/- 316 and 1,295 +/- 376 mu g/mL, respectively. VRC07-523LS administration significantly decreased VL in 8 out of 9 participants, with an average decline of 1.7 +/- 0.8 log(10) copies/mL within 14 days after administration. In contrast, VRC01LS administration resulted in a smaller average decline (0.8 +/- 0.8 log(10) copies/mL), and 3 out of 7 participants showedno change in VL. Postinfusion maximum decline in VL correlated with post hoc baseline in vitro viral susceptibility results for both bNAbs. CONCLUSION. The results of this trial support inclusion of potent CD4bs-specific bNAbs, such as VRC07-523LS, into next-generation treatment regimens for HIV-1. TRIAL REGISTRATION. ClinicalTrials.gov NCT02840474.