SARS-CoV-2 RNA and Nucleocapsid Antigen Are Blood Biomarkers Associated With Severe Disease Outcomes That Improve in Response to Remdesivir.

BACKGROUND: Although antivirals remain important for the treatment COVID-19, methods to assess treatment efficacy are lacking. Here, we investigated the impact of remdesivir on viral dynamics and their contribution to understanding antiviral efficacy in the multicenter Adaptive COVID-19 Treatment Trial 1, which randomized patients to remdesivir or placebo. METHODS: Longitudinal specimens collected during hospitalization from a substudy of 642 patients with COVID-19 were measured for viral RNA (upper respiratory tract and plasma), viral nucleocapsid antigen (serum), and host immunologic markers. Associations with clinical outcomes and response to therapy were assessed. RESULTS: Higher baseline plasma viral loads were associated with poorer clinical outcomes, and decreases in viral RNA and antigen in blood but not the upper respiratory tract correlated with enhanced benefit from remdesivir. The treatment effect of remdesivir was most pronounced in patients with elevated baseline nucleocapsid antigen levels: the recovery rate ratio was 1.95 (95% CI, 1.40-2.71) for levels >245 pg/mL vs 1.04 (95% CI, .76-1.42) for levels <245 pg/mL. Remdesivir also accelerated the rate of viral RNA and antigen clearance in blood, and patients whose blood levels decreased were more likely to recover and survive. CONCLUSIONS: Reductions in SARS-CoV-2 RNA and antigen levels in blood correlated with clinical benefit from antiviral therapy. CLINICAL TRIAL REGISTRATION: NCT04280705 (ClinicalTrials.gov).

Molecular Imaging of Infections: Advancing the Search for the Hidden Enemy.

Even before the coronavirus disease 2019 pandemic, infections were a major threat to human health, as the third leading cause of death and the leading cause of morbidity among all human diseases. Although conventional imaging studies are routinely used for patients with infections, they provide structural or anatomic information only. Molecular imaging technologies enable noninvasive visualization of molecular processes at the cellular level within intact living subjects, including patients, and hold great potential for infections. We hope that this supplement will spur interest in the field and establish new collaborations to develop and translate novel molecular imaging approaches to the clinic.

Immune reconstitution in HIV infection.

The weight of the published evidence suggest that there is clinically significant immune recovery in a sizable fraction of HIV-infected patients who achieve suppression of viral replication. At the same time, it is clear that very few patients regain normal (i.e. equivalent to pre-infection) immune function, at least after the follow-up periods available so far. The experience from bone-marrow transplantation or intensive chemotherapy in adults suggests that such kind of immune reconstitution is unlikely (at least with treatments limited to stopping virus replication) once the immune system has been sufficiently damaged. It is also clear that effective immunity to HIV is not achieved in a significant proportion of patients. These findings have implications for both basic research and clinical practice. From the laboratory perspective, besides the urgent need to characterize the protective immunity to HIV (if it exists), it would be desirable to find some simple measure of the immune function of patients who receive therapy. The combination of markers of immune activation together with CD4 cell count and viral load should be further evaluated in this context. Regarding clinical practice, it is likely that prophylaxes for opportunistic infections can be discontinued uneventfully in the majority of patients responding to HAART. Although the evidence is not yet conclusive, all available data suggest this will be the case. Given that there is significant immune reconstitution even in advanced disease, it is tempting to consider if this fact can be used to support antiviral therapy recommendations that are less aggressive than the current ones. HIV eradication by pharmacologic means alone does not seem possible yet, and no effective immune response to HIV seems to be generated by starting therapy in the asymptomatic (as opposed to acute infection) stage of the disease. At the same time, the follow-up studies on prolonged antiretroviral therapy suggest that virologic failure will take place despite many months of seemingly adequate suppression. This fact, taken together with the side effects and inconvience of current antiretroviral regimens, can be used to support an argument in favor of evaluating strategies to treat later rather than earlier.

A model of federal interagency cooperation: the National Interagency Confederation for Biological Research.

The terrorist attacks of September 11 and the anthrax mailings a month later prompted a sweeping response by the federal government to improve the preparedness of the US to meet the potential threat posed by a terrorist using a biological agent. This response transcended traditional interagency boundaries, creating new opportunities while producing unique fiscal and leadership challenges. The National Interagency Confederation for Biological Research has made significant progress over the past 12 years because of its ability to adapt to the need for interagency cooperation and overcome many of these challenges. As construction of the National Interagency Biodefense Campus at Fort Detrick nears completion, the US has the capability to pursue a unique whole-of-government approach to the development of medical measures to counter the threat of bioterrorism. In addition to the high-level support of many in the federal government, the key success factors for this effort have been (1) a critical mass of leaders with the right leadership characteristics, (2) development of a compelling vision and accompanying narrative understood and articulated by all partnering organizations, and (3) recognition of the need for a partnership office to do the important communication and collaboration work in the organization to synchronize the information available to all the partners. The major barrier to interagency cooperative efforts of this kind is the inability to comingle funds from different appropriations.