Immune correlates analysis of a phase 3 trial of the AZD1222 (ChAdOx1 nCoV-19) vaccine.

In the phase 3 trial of the AZD1222 (ChAdOx1 nCoV-19) vaccine conducted in the U.S., Chile, and Peru, anti-spike binding IgG concentration (spike IgG) and pseudovirus 50% neutralizing antibody titer (nAb ID50) measured four weeks after two doses were assessed as correlates of risk and protection against PCR-confirmed symptomatic SARS-CoV-2 infection (COVID-19). These analyses of SARS-CoV-2 negative participants were based on case-cohort sampling of vaccine recipients (33 COVID-19 cases by 4 months post dose two, 463 non-cases). The adjusted hazard ratio of COVID-19 was 0.32 (95% CI: 0.14, 0.76) per 10-fold increase in spike IgG concentration and 0.28 (0.10, 0.77) per 10-fold increase in nAb ID50 titer. At nAb ID50 below the limit of detection (< 2.612 IU50/ml), 10, 100, and 270 IU50/ml, vaccine efficacy was -5.8% (-651%, 75.6%), 64.9% (56.4%, 86.9%), 90.0% (55.8%, 97.6%) and 94.2% (69.4%, 99.1%). These findings provide further evidence towards defining an immune marker correlate of protection to help guide regulatory/approval decisions for COVID-19 vaccines.

AZD1222-induced nasal antibody responses are shaped by prior SARS-CoV-2 infection and correlate with virologic outcomes in breakthrough infection.

The nasal mucosa is an important initial site of host defense against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, intramuscularly administered vaccines typically do not achieve high antibody titers in the nasal mucosa. We measure anti-SARS-CoV-2 spike immunoglobulin G (IgG) and IgA in nasal epithelial lining fluid (NELF) following intramuscular vaccination of 3,058 participants from the immunogenicity substudy of a phase 3, double-blind, placebo-controlled study of AZD1222 vaccination (ClinicalTrials.gov: NCT04516746). IgG is detected in NELF collected 14 days following the first AZD1222 vaccination. IgG levels increase with a second vaccination and exceed pre-existing levels in baseline-SARS-CoV-2-seropositive participants. Nasal IgG responses are durable and display strong correlations with serum IgG, suggesting serum-to-NELF transudation. AZD1222 induces short-lived increases to pre-existing nasal IgA levels in baseline-seropositive vaccinees. Vaccinees display a robust recall IgG response upon breakthrough infection, with overall magnitudes unaffected by time between vaccination and illness. Mucosal responses correlate with reduced viral loads and shorter durations of viral shedding in saliva.

Durability of protection and immunogenicity of AZD1222 (ChAdOx1 nCoV-19) COVID-19 vaccine over 6 months.

BackgroundWe report updated safety, efficacy, and immunogenicity of AZD1222 (ChAdOx1 nCoV-19) from an ongoing phase 3 trial.MethodsAdults at increased risk of SARS-CoV-2 infection were randomized (2:1), stratified by age, to receive 2 doses of AZD1222 or placebo. The primary efficacy end point was confirmed SARS-CoV-2 reverse-transcriptase PCR-positive (RT-PCR-positive) symptomatic COVID-19 at 15 or more days after a second dose in baseline SARS-CoV-2-seronegative participants. The 21,634 and 10,816 participants were randomized to AZD1222 and placebo, respectively.FindingsData cutoff for this analysis was July 30, 2021; median follow-up from second dose was 78 and 71 days for the double-blind period (censoring at unblinding or nonstudy COVID-19 vaccination) and 201 and 82 days for the period to nonstudy COVID-19 vaccination (regardless of unblinding) in the AZD1222 and placebo groups, respectively. For the primary efficacy end point in the double-blind period (141 and 184 events; incidence rates: 39.2 and 118.8 per 1,000 person years), vaccine efficacy was 67.0% (P < 0.001). In the period to nonstudy COVID-19 vaccination, incidence of events remained consistently low and stable through 6 months in the AZD1222 group; for the primary efficacy end point (328 and 219 events; incidence rates: 36.4, 108.4) and severe/critical disease (5 and 13 events; incidence rates: 0.6, 6.4), respective vaccine efficacy estimates were 65.1% and 92.1%. AZD1222 elicited humoral immune responses over time, with waning at day 180. No emergent safety issues were seen.ConclusionAZD1222 is safe and well tolerated, demonstrating durable protection and immunogenicity with median follow-up (AZD1222 group) of 6 months.Trial registrationClinicalTrials.gov NCT04516746.FundingAstraZeneca; US government.

Long-term effects of dapagliflozin plus saxagliptin versus glimepiride on a background of metformin in patients with type 2 diabetes: Results of a 104-week extension to a 52-week randomized, phase 3 study and liver fat MRI substudy.

AIM: To report the results of a 104-week extension to a 52-week study in which dapagliflozin plus saxagliptin (DAPA+SAXA) improved glycaemic control, liver fat and metabolic variables compared with glimepiride (GLIM) in participants with type 2 diabetes (T2D) receiving background metformin. MATERIALS AND METHODS: This extension to a 52-week global, multicentre, parallel-group, active-controlled, double-blind study (NCT02419612) continued randomized participants (1:1) on DAPA+SAXA (10/5 mg) plus placebo, or GLIM (1-6 mg) plus placebo, once daily. Eligible participants were aged ≥18 years, had T2D (glycated haemoglobin [HbA1c] 58.5-91.3 mmol/mol [7.5%-10.5%]), and a body mass index of 20.0 to 45.0 kg/m2 , and were receiving metformin (MET; ≥1500 mg/d). Key outcomes were: requirement for treatment intensification, based on HbA1c ≥53 mmol/mol (7%); achieving therapeutic glycaemic response; and changes in adipose tissue and liver fat on magnetic resonance imaging in a substudy. RESULTS: Overall, 382 participants entered and 338 completed the 104-week extension period (MRI substudy, n = 82). The need for treatment intensification during the 156-week period was lower for DAPA+SAXA+MET (37.0%) than GLIM+MET (55.6%; hazard ratio 0.52, 95% confidence interval [CI] 0.39-0.68; P < 0.001). At week 156, 21.4% of DAPA+SAXA+MET versus 11.7% of GLIM+MET participants achieved therapeutic glycaemic response (HbA1c <53 mmol/mol; odds ratio 2.1, 95% CI 1.23-3.42; P = 0.006). DAPA+SAXA+MET led to greater adjusted mean reductions from baseline in liver fat and visceral and subcutaneous adipose tissue volumes versus GLIM+MET at week 122 (least-squares mean difference from GLIM+MET -4.89%, -0.41 L and -0.44 L, respectively; nominal P values ≤ 0.008). Safety was consistent with that of the monocomponents. CONCLUSIONS: Overall, glycaemic control, metabolic benefits and efficacy were better maintained with DAPA+SAXA+MET than with GLIM+MET in T2D.

Robust humoral and cellular recall responses to AZD1222 attenuate breakthrough SARS-CoV-2 infection compared to unvaccinated.

Background: Breakthrough severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in coronavirus disease 2019 (COVID-19) vaccinees typically produces milder disease than infection in unvaccinated individuals. Methods: To explore disease attenuation, we examined COVID-19 symptom burden and immuno-virologic responses to symptomatic SARS-CoV-2 infection in participants (AZD1222: n=177/17,617; placebo: n=203/8,528) from a 2:1 randomized, placebo-controlled, phase 3 study of two-dose primary series AZD1222 (ChAdOx1 nCoV-19) vaccination (NCT04516746). Results: We observed that AZD1222 vaccinees had an overall lower incidence and shorter duration of COVID-19 symptoms compared with placebo recipients, as well as lower SARS-CoV-2 viral loads and a shorter median duration of viral shedding in saliva. Vaccinees demonstrated a robust antibody recall response versus placebo recipients with low-to-moderate inverse correlations with virologic endpoints. Vaccinees also demonstrated an enriched polyfunctional spike-specific Th-1-biased CD4+ and CD8+ T-cell response that was associated with strong inverse correlations with virologic endpoints. Conclusion: Robust immune responses following AZD1222 vaccination attenuate COVID-19 disease severity and restrict SARS-CoV-2 transmission potential by reducing viral loads and the duration of viral shedding in saliva. Collectively, these analyses underscore the essential role of vaccination in mitigating the COVID-19 pandemic.

Phase 3 Safety and Efficacy of AZD1222 (ChAdOx1 nCoV-19) Covid-19 Vaccine.

BACKGROUND: The safety and efficacy of the AZD1222 (ChAdOx1 nCoV-19) vaccine in a large, diverse population at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the United States, Chile, and Peru has not been known. METHODS: In this ongoing, double-blind, randomized, placebo-controlled, phase 3 clinical trial, we investigated the safety, vaccine efficacy, and immunogenicity of two doses of AZD1222 as compared with placebo in preventing the onset of symptomatic and severe coronavirus disease 2019 (Covid-19) 15 days or more after the second dose in adults, including older adults, in the United States, Chile, and Peru. RESULTS: A total of 32,451 participants underwent randomization, in a 2:1 ratio, to receive AZD1222 (21,635 participants) or placebo (10,816 participants). AZD1222 was safe, with low incidences of serious and medically attended adverse events and adverse events of special interest; the incidences were similar to those observed in the placebo group. Solicited local and systemic reactions were generally mild or moderate in both groups. Overall estimated vaccine efficacy was 74.0% (95% confidence interval [CI], 65.3 to 80.5; P<0.001) and estimated vaccine efficacy was 83.5% (95% CI, 54.2 to 94.1) in participants 65 years of age or older. High vaccine efficacy was consistent across a range of demographic subgroups. In the fully vaccinated analysis subgroup, no severe or critical symptomatic Covid-19 cases were observed among the 17,662 participants in the AZD1222 group; 8 cases were noted among the 8550 participants in the placebo group (<0.1%). The estimated vaccine efficacy for preventing SARS-CoV-2 infection (nucleocapsid antibody seroconversion) was 64.3% (95% CI, 56.1 to 71.0; P<0.001). SARS-CoV-2 spike protein binding and neutralizing antibodies increased after the first dose and increased further when measured 28 days after the second dose. CONCLUSIONS: AZD1222 was safe and efficacious in preventing symptomatic and severe Covid-19 across diverse populations that included older adults. (Funded by AstraZeneca and others; ClinicalTrials.gov number, NCT04516746.).

Dapagliflozin plus saxagliptin add-on to metformin reduces liver fat and adipose tissue volume in patients with type 2 diabetes.

AIM: To assess the effects of dapagliflozin plus saxagliptin plus metformin versus glimepiride plus metformin on liver fat (proton density fat fraction) and visceral and subcutaneous adipose tissue volumes over 52 weeks of treatment. MATERIALS AND METHODS: This was a magnetic resonance imaging substudy of a 52-week, multicentre, randomized, double-blind, parallel-group trial that evaluated the efficacy and safety of dapagliflozin 10 mg/day plus saxagliptin 5 mg/day versus titrated glimepiride 1-6 mg (1, 2, 3, 4 or 6 mg) in 82 patients with type 2 diabetes (HbA1c 7.5%-10.5%) on metformin ≥1500 mg/day background. Analyses were exploratory and not controlled for multiplicity; P-values are nominal. RESULTS: Magnetic resonance imaging was performed on 59 patients; liver fat and adipose tissue volumes were analysed for 59 and 57 patients, respectively. There was a significant >30% reduction from baseline in liver fat (P = 0.007) and >10% reduction in adipose tissue volumes (P < 0.01) with dapagliflozin plus saxagliptin plus metformin at week 52 versus glimepiride plus metformin. In the full-study population, dapagliflozin plus saxagliptin plus metformin decreased body weight and serum alanine aminotransferase and aspartate aminotransferase levels over 52 weeks. CONCLUSIONS: Dapagliflozin plus saxagliptin significantly decreased liver fat and adipose tissue volume versus glimepiride, and reduced serum liver enzyme levels, indicating a favourable metabolic profile of dapagliflozin plus saxagliptin in patients with type 2 diabetes on metformin therapy.

Efficacy and safety of dual add-on therapy with dapagliflozin plus saxagliptin versus glimepiride in patients with poorly controlled type 2 diabetes on a stable dose of metformin: Results from a 52-week, randomized, active-controlled trial.

AIMS: To evaluate the efficacy and safety of dapagliflozin (DAPA) + saxagliptin (SAXA) compared with glimepiride (GLIM) in patients with type 2 diabetes who were inadequately controlled [glycated haemoglobin (HbA1c) 7.5-10.5% (58-91 mmol/mol)] on metformin monotherapy. MATERIALS AND METHODS: This 52-week, multicentre, double-blind, active-controlled study (NCT02419612) randomized (1:1) patients on metformin to add-on DAPA 10 mg + SAXA 5 mg (n = 227) or GLIM 1-6 mg (titrated; n = 217). The primary efficacy endpoint was change in HbA1c from baseline to week 52. RESULTS: Baseline mean ± standard deviation of age, duration of diabetes and HbA1c were 56.1 ± 9.7 years, 7.8 ± 6.4 years and 8.5% ± 0.8% (69 ± 9.0 mmol/mol), respectively. Adjusted mean change from baseline in HbA1c was -1.35% (-14.8 mmol/mol) with DAPA + SAXA versus -0.98% (-10.7 mmol/mol) with GLIM (P <0.001). Changes from baseline in body weight and systolic blood pressure were -3.1 kg and -2.6 mmHg with DAPA + SAXA versus +1.0 kg (P <0.001) and +1.0 mmHg (P = 0.007) with GLIM. More patients achieved HbA1c <7.0% (53 mmol/mol) (44.3% vs. 34.3%; P = 0.044), and fewer patients required treatment intensification (1.3% vs. 8.8%; P = 0.002) with DAPA + SAXA than with GLIM. CONCLUSIONS: Compared with GLIM, concurrent addition of DAPA + SAXA significantly improved glycaemic control, body weight and other metabolic parameters in patients inadequately controlled on metformin. Trial: NCT02419612, ClinicalTrials.gov.

The association between glycemic control and clinical outcomes after kidney transplantation.

OBJECTIVE: To analyze the relationship between glycemic control after renal transplantation and subsequent graft function and complications. METHODS: We conducted a retrospective chart review of 202 consecutive patients undergoing kidney transplantation to analyze the association between perioperative and chronic glycemic control and clinical outcomes of rejection, infection, and hospital readmission during the first year after kidney transplantation. RESULTS: Mean in-hospital blood glucose (BG) was 157 ± 34.5 mg/dL. Mean hemoglobin A1c (HbA1c) during the first 12 months posttransplantation was 6.84 ± 1.46%. Fiftyfour patients (27%) were treated for acute or chronic rejection, 88 (44%) for infection, and 149 (74%) patients were readmitted at least once within the first year after transplantation. There were no significant differences in the risks for rejection, infection, or readmission across the 5 mean initial inpatient BG or subsequent HbA1c quintiles. In addition, there was no significant relationship between the percentage of BG measurements that fell in the "tight control" range of 80 to 110 mg/dL for each patient and any of the outcomes. CONCLUSION: We did not find an association between glycemic control (perioperative or chronic) and the outcomes of graft rejection, infection, or hospital readmission in the first 12 months after renal transplantation. Our results suggest that "near normal" glycemic targets are not necessary for managing hyperglycemia after renal transplantation.