Baricitinib set to join the Covid-19 therapeutic arsenal?

Efficacy and safety of baricitinib or ravulizumab in adult patients with severe COVID-19 (TACTIC-R): a randomised, parallel-arm, open-label, phase 4 trial

BACKGROUND

From early in the COVID-19 pandemic, evidence suggested a role for cytokine dysregulation and complement activation in severe disease. In the TACTIC-R trial, we evaluated the efficacy and safety of baricitinib, an inhibitor of Janus kinase 1 (JAK1) and JAK2, and ravulizumab, a monoclonal inhibitor of complement C5 activation, as an adjunct to standard of care for the treatment of adult patients hospitalised with COVID-19.

METHODS

TACTIC-R was a phase 4, randomised, parallel-arm, open-label platform trial that was undertaken in the UK with urgent public health designation to assess the potential of repurposing immunosuppressants for the treatment of severe COVID-19, stratified by a risk score. Adult participants (aged ≥18 years) were enrolled from 22 hospitals across the UK. Patients with a risk score indicating a 40% risk of admission to an intensive care unit or death were randomly assigned 1:1:1 to standard of care alone, standard of care with baricitinib, or standard of care with ravulizumab. The composite primary outcome was the time from randomisation to incidence (up to and including day 14) of the first event of death, invasive mechanical ventilation, extracorporeal membrane oxygenation, cardiovascular organ support, or renal failure. The primary interim analysis was triggered when 125 patient datasets were available up to day 14 in each study group and we included in the analysis all participants who were randomly assigned. The trial was registered on ClinicalTrials.gov (NCT04390464).

FINDINGS

Between May 8, 2020, and May 7, 2021, 417 participants were recruited and randomly assigned to standard of care alone (145 patients), baricitinib (137 patients), or ravulizumab (135 patients). Only 54 (39%) of 137 patients in the baricitinib group received the maximum 14-day course, whereas 132 (98%) of 135 patients in the ravulizumab group received the intended dose. The trial was stopped after the primary interim analysis on grounds of futility. The estimated hazard ratio (HR) for reaching the composite primary endpoint was 1·11 (95% CI 0·62-1·99) for patients on baricitinib compared with standard of care alone, and 1·53 (0·88-2·67) for ravulizumab compared with standard of care alone. 45 serious adverse events (21 deaths) were reported in the standard-of-care group, 57 (24 deaths) in the baricitinib group, and 60 (18 deaths) in the ravulizumab group.

INTERPRETATION

Neither baricitinib nor ravulizumab, as administered in this study, was effective in reducing disease severity in patients selected for severe COVID-19. Safety was similar between treatments and standard of care. The short period of dosing with baricitinib might explain the discrepancy between our findings and those of other trials. The therapeutic potential of targeting complement C5 activation product C5a, rather than the cleavage of C5, warrants further evaluation.

FUNDING

UK Medical Research Council, UK National Institute for Health Research Cambridge Biomedical Research Centre, Eli Lilly and Company, Alexion Pharmaceuticals, and Addenbrooke's Charitable Trust.

A narrative review on tofacitinib: The properties, function, and usefulness to treat coronavirus disease 2019

In coronavirus disease 2019 (COVID-19), the formation of cytokine storm may have a role in worsening of the disease. By attaching the cytokines like interleukin-6 to the cytokine receptors on a cell surface, Janus kinase (JAK)-signal transducers and activators of transcription (STAT) pathway will be activated in the cytoplasm lead to hyperinflammatory conditions and acute respiratory distress syndrome. Inhibition of JAK/STAT pathway may be useful to prevent the formation of cytokine storm. Tofacitinib is a pan inhibitor of JAKs. In this review, the main characteristics of tofacitinib and its usefulness against COVID-19 pneumonia were reviewed. Tofacitinib may be a hopeful therapeutic candidate against COVID-19 respiratory injury since it inhibits a range of inflammatory pathways. Hence, the agent may be considered a potential therapeutic against the post-COVID-19 respiratory damage. Compared to other JAK inhibitors (JAKi), the administration of tofacitinib in COVID-19 patients may be safer and more effective. Other JAKi such as baricitinib are related to severe adverse events such as thrombotic events compared to more common side effects of tofacitinib.

Therapeutic and anti-inflammatory effects of baricitinib on mortality, ICU transfer, clinical improvement, and CRS-related laboratory parameters of hospitalized patients with moderate to severe COVID-19 pneumonia: a systematic review and meta-analysis

BACKGROUND

Due to the high incidence and mortality of the worldwide COVID-19 pandemic, beneficial effects of effective antiviral and anti-inflammatory drugs used in other diseases, especially rheumatic diseases, were observed in the treatment of COVID-19.

METHODS

Clinical and laboratory parameters of eight included cohort studies and five Randomized Control Trials between the baricitinib group and the control group were analyzed on the first day of admission and days 7, 14, and 28 during hospitalization.

RESULTS

According to the meta-analysis result of eight included cohort studies with 2088 patients, the Pooled Risk Ratios were 0.46 (P<0.001) for mortality, 6.14 (P< 0.001) for hospital discharge, and the mean differences of 76.78 (P< 0.001) for PaO₂/FiO₂ ratio was -47.32 (P= 0.02) for CRP, in the baricitinib group vs. control group on the seventh or fourteenth day of the treatment compared to the first day. Based on the meta-analysis of five RCT studies with 11825 patients, the pooled RR was 0.84 (P= 0.001) for mortality and 1.07 (P= 0.014) for patients' recovery. The mean differences were -0.80 (P<0.001) for hospitalization days, -0.51(P= 0.33) for time to recovery in the baricitinib group vs. control group.

CONCLUSIONS

Baricitinib prescription is strongly recommended in moderate to severe COVID-19.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number: CRD42021254541.

Early Use of Low-Dose Ruxolitinib: A Promising Strategy for the Treatment of Acute and Chronic GVHD

Janus kinases (JAK) are a family of tyrosine kinases (JAK1, JAK2, JAK3, and TYK2) that transduce cytokine-mediated signals through the JAK–STAT metabolic pathway. These kinases act by regulating the transcription of specific genes capable of inducing biological responses in several immune cell subsets. Inhibition of Janus kinases interferes with the JAK–STAT signaling pathway. Besides being used in the treatment of cancer and inflammatory diseases, in recent years, they have also been used to treat inflammatory conditions, such as graft-versus-host disease (GVHD) and cytokine release syndrome as complications of allogeneic hematopoietic stem cell transplantation and cell therapy. Recently, the FDA approved the use of ruxolitinib, a JAK1/2 inhibitor, in the treatment of acute steroid-refractory GVHD (SR-aGVHD), highlighting the role of JAK inhibition in this immune deregulation. Ruxolitinib was initially used to treat myelofibrosis and true polycythemia in a high-dose treatment and caused hematological toxicity. Since a lower dosage often could not be effective, the use of ruxolitinib was suspended. Subsequently, ruxolitinib was evaluated in adult patients with SR-aGVHD and was found to achieve a rapid and effective response. In addition, its early low-dose use in pediatric patients affected by GVHD has proved effective, safe, and reasonably preventive. The review aims to describe the potential properties of ruxolitinib to identify new therapeutic strategies.