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A Risk Profile Using Simple Hematologic Parameters to Assess Benefits From Baricitinib in Patients Hospitalized With
Catharine I Paules1, Jing Wang2, Kay M Tomashek3
1Division of Infectious Diseases, Penn State Health Milton S. Hershey Medical Center, Hershey, Pennsylvania (C.I.P.).
Insights
Hospitalized COVID-19 patients in a high-risk group showed improved outcomes with baricitinib plus remdesivir. This immunomodulator treatment reduced mortality and enhanced recovery in severe cases.
Area of Science:
- Infectious Diseases
- Immunology
- Critical Care Medicine
Background:
- The ACTT risk profile identified high-risk COVID-19 patients (low ALC, high ANC, low platelets) benefiting from remdesivir.
- Benefit from baricitinib, an immunomodulator, in specific COVID-19 patient subgroups remained unclear.
Purpose of the Study:
- To evaluate baricitinib treatment effects in COVID-19 patients stratified by the ACTT risk profile.
- To identify patient characteristics associated with baricitinib benefit in hospitalized COVID-19 patients.
Main Methods:
- Post hoc analysis of the randomized, double-blind, placebo-controlled ACTT-2 trial (NCT04401579).
- Included 999 hospitalized adult COVID-19 patients, with baricitinib+remdesivir compared to placebo+remdesivir.
- Assessed mortality, progression to invasive mechanical ventilation (IMV) or death, recovery, and blood cell count trajectories within 28 days.
Main Results:
- In the high-risk quartile, baricitinib+remdesivir significantly reduced the risk of death (HR 0.38) and progression to IMV or death (HR 0.57).
- Improved recovery rates (HR 1.53) were observed in the high-risk group receiving baricitinib+remdesivir.
- Baricitinib+remdesivir led to greater increases in absolute lymphocyte count (ALC) and decreases in absolute neutrophil count (ANC), particularly in high-risk patients.
Conclusions:
- The ACTT risk profile identifies COVID-19 patients who benefit most from baricitinib treatment.
- Baricitinib, as an immunomodulator, combined with an antiviral, demonstrates a potential mechanism for limiting severe COVID-19 progression through modulation of ALC and ANC levels.
Background:
The ACTT risk profile, which was developed from ACTT-1 (Adaptive COVID-19 Treatment Trial-1), demonstrated that hospitalized patients with COVID-19 in the high-risk quartile (characterized by low absolute lymphocyte count [ALC], high absolute neutrophil count [ANC], and low platelet count at baseline) benefited most from treatment with the antiviral remdesivir. It is unknown which patient characteristics are associated with benefit from treatment with the immunomodulator baricitinib.
Objective:
To apply the ACTT risk profile to the ACTT-2 cohort to investigate potential baricitinib-related treatment effects by risk quartile.
Design:
Post hoc analysis of ACTT-2, a randomized, double-blind, placebo-controlled trial. (ClinicalTrials.gov: NCT04401579).
Setting:
Sixty-seven trial sites in 8 countries.
Participants:
Adults hospitalized with COVID-19 (n = 999; 85% U.S. participants).
Intervention:
Baricitinib+remdesivir versus placebo+remdesivir.
Measurements:
Mortality, progression to invasive mechanical ventilation (IMV) or death, and recovery, all within 28 days; ALC, ANC, and platelet count trajectories.
Results:
In the high-risk quartile, baricitinib+remdesivir was associated with reduced risk for death (hazard ratio [HR], 0.38 [95% CI, 0.16 to 0.86]; P = 0.020), decreased progression to IMV or death (HR, 0.57 [CI, 0.35 to 0.93]; P = 0.024), and improved recovery rate (HR, 1.53 [CI, 1.16 to 2.02]; P = 0.002) compared with placebo+remdesivir. After 5 days, participants receiving baricitinib+remdesivir had significantly larger increases in ALC and significantly larger decreases in ANC compared with control participants, with the largest effects observed in the high-risk quartile.
Limitation:
Secondary analysis of data collected before circulation of current SARS-CoV-2 variants.
Conclusion:
The ACTT risk profile identifies a subgroup of hospitalized patients who benefit most from baricitinib treatment and captures a patient phenotype of treatment response to an immunomodulator and an antiviral. Changes in ALC and ANC trajectory suggest a mechanism whereby an immunomodulator limits severe COVID-19.
Primary Funding Source:
National Institute of Allergy and Infectious Diseases.
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