Tocilizumab in patients hospitalised with COVID-19 pneumonia: Efficacy, safety, viral clearance, and antibody response from a randomised controlled trial (COVACTA).

Background: In COVACTA, a randomised, placebo-controlled trial in patients hospitalised with coronavirus disease-19 (COVID-19), tocilizumab did not improve 28-day mortality, but shortened hospital and intensive care unit stay. Longer-term effects of tocilizumab in patients with COVID-19 are unknown. Therefore, the efficacy and safety of tocilizumab in COVID-19 beyond day 28 and its impact on Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) clearance and antibody response in COVACTA were investigated. Methods: Adults in Europe and North America hospitalised with COVID-19 (N = 452) between April 3, 2020 and May 28, 2020 were randomly assigned (2:1) to double-blind intravenous tocilizumab or placebo and assessed for efficacy and safety through day 60. Assessments included mortality, time to hospital discharge, SARS-CoV-2 viral load in nasopharyngeal swab and serum samples, and neutralising anti-SARS-CoV-2 antibodies in serum. ClinicalTrials.gov registration: NCT04320615. Findings: By day 60, 24·5% (72/294) of patients in the tocilizumab arm and 25·0% (36/144) in the placebo arm died (weighted difference -0·5% [95% CI -9·1 to 8·0]), and 67·0% (197/294) in the tocilizumab arm and 63·9% (92/144) in the placebo arm were discharged from the hospital. Serious infections occurred in 24·1% (71/295) of patients in the tocilizumab arm and 29·4% (42/143) in the placebo arm. Median time to negative reverse transcriptase-quantitative polymerase chain reaction result in nasopharyngeal/oropharyngeal samples was 15·0 days (95% CI 14·0 to 21·0) in the tocilizumab arm and 21·0 days (95% CI 14·0 to 28·0) in the placebo arm. All tested patients had positive test results for neutralising anti-SARS-CoV-2 antibodies at day 60. Interpretation: There was no mortality benefit with tocilizumab through day 60. Tocilizumab did not impair viral clearance or host immune response, and no new safety signals were observed. Future investigations may explore potential biomarkers to optimize patient selection for tocilizumab treatment and combination therapy with other treatments. Funding: F. Hoffmann-La Roche Ltd and the US Department of Health and Human Services, Office of the Assistant Secretary for Preparedness and Response, Biomedical Advanced Research and Development Authority, under OT number HHSO100201800036C.

Validation of calcaneus trabecular microstructure measurements by HR-pQCT.

OBJECTIVE: Assessment of calcaneus microstructure using high-resolution peripheral quantitative computed tomography (HR-pQCT) might be used to improve fracture risk predictions or to assess responses to pharmacological and physical interventions. To develop a standard clinical protocol for the calcaneus, we validated calcaneus trabecular microstructure measured by HR-pQCT against 'gold-standard' micro-CT measurements. METHODS: Ten human cadaveric feet were scanned in situ using HR-pQCT (isotropic 82µm voxel size) at 100, 150 and 200ms integration times, and at 100ms integration time following removal of the calcaneus from the foot (ex vivo). Dissected portions of these bones were scanned using micro-computed tomography (micro-CT) at an isotropic 17.4µm voxel size. HR-pQCT images were rigidly registered to those obtained with micro-CT and divided into multiple 5mm sided cubes to evaluate and compare morphometric parameters between the modalities. Standard HR-pQCT measurements (derived bone volume fraction (BV/TVd); trabecular number, Tb.N; derived trabecular thickness, Tb.Thd; derived trabecular spacing, Tb.Spd) and corresponding micro-CT voxel-based measurements (BV/TV, Tb.N, Tb.Th, Tb.Sp) were compared. RESULTS: A total of 108 regions of interest were analysed across the 10 specimens. At all integration times HR-pQCT BV/TVd was strongly correlated with micro-CT BV/TV (r2=0.95-0.98, RMSE=1%), but BV/TVd was systematically lower than that measured by micro-CT (mean bias=5%). In contrast, HR-pQCT systematically overestimated Tb.N at all integration times; of the in situ scans, 200ms yielded the lowest mean bias and the strongest correlation with micro-CT (r2=0.61, RMSE=0.15mm-1). Regional analysis revealed greater accuracy for Tb.N in the superior regions of the calcaneus at all integration times in situ (mean bias=0.44-0.85mm-1; r2=0.70-0.88, p<0.001 versus mean bias=0.63-1.46mm-1; r2≤0.08, p≥0.21 for inferior regions). Tb.Spd was underestimated by HR-pQCT compared to micro-CT, but showed similar trends with integration time and the region evaluated as Tb.N. HR-pQCT Tb.Thd was also underestimated and moderately correlated (r2=0.53-0.59) with micro-CT Tb.Th, independently from the integration time. Stronger correlations, smaller biases and error were found in the scans of the calcaneus ex vivo compared to in situ. CONCLUSION: Calcaneus trabecular BV/TVd and trabecular microstructure, particularly in the superior region of the calcaneus, can be assessed by HR-pQCT. The highest integration time examined, 200ms, compared best with micro-CT. Weaker correlations for microstructure at inferior regions, and also with lower integration times, might limit the use of the proposed protocol, which warrants further investigation in vivo.

The effects of parathyroid hormone peptides on the peripheral skeleton of postmenopausal women. A systematic review.

Given current developments in anabolic therapy for bone, we wished to document the effects of the only currently available anabolic therapy, parathyroid hormone (PTH) peptides, on the peripheral skeleton of postmenopausal women. We undertook a systematic review of English articles using MEDLINE, Scopus and the Cochrane Controlled Trials Register (final update 28th March 2016). Additional studies were identified through searches of bibliographies. Studies included those comparing PTH peptides with placebo, with anti-osteoporotic treatments and in combination therapies. Participants had to be postmenopausal women and outcomes included areal or volumetric bone mineral density (BMD) and measurements of bone microarchitecture at peripheral sites, such as the forearm and tibia. Data were extracted independently and reviewed by EVM and LMM. Data on study design were also collected for methodological risk of bias assessment. The heterogeneity between studies, regarding the drug dose and duration, and the site measured, prevented grouped meta-analysis. There were no significant differences in areal BMD between PTH peptides and placebo at peripheral skeletal sites at 12months. A decrease in aBMD occurred with PTH(1-34) (larger dose) and PTH(1-84) treatment at 18months follow-up in comparison to the placebo arms. Anti-resorptives seemed to attenuate losses of aBMD at peripheral sites when compared to PTH peptides monotherapy, likely mediated by lower cortical porosity. Finally, PTH peptides combined with bisphosphonates or denosumab attenuated peripheral BMD losses in comparison to PTH peptide monotherapy, with evidence of increased BMD at ultradistal peripheral sites when PTH(1-34) was combined with denosumab or hormone replacement therapy. This summary should act as a reference point for the comparison of new anabolic therapies, specifically in comparison to PTH(1-34).