The National Library of Medicine’s clinicaltrials.gov registry of federally funded clinical studies lists 15 current research initiatives involving baricitinib and COVID-19. Dr. Stebbing suggested that data generated so far are helping to guide ongoing studies on dose and duration of treatment – in other words, who it works for, when to give it, and at what dose it should be taken and for how long.
Manufacturer Eli Lilly, which markets baricitinib in 2-mg or 4-mg tablets, announced in October that initial data are starting to emerge from 1,000-plus patients enrolled in ACTT-2 (the Adaptive COVID-19 Treatment Trial 2). ACTT-2 compared patients on the broad-spectrum intravenous antiviral drug remdesivir (Veklury) with those receiving remdesivir in combination with baricitinib. Based on ACTT-2 results that suggested a reduced time to recovery and improved clinical outcomes for the combination group, the FDA issued an emergency-use authorization on Nov. 19 for the combination of baricitinib and remdesivir for the treatment of suspected or laboratory confirmed COVID-19 in hospitalized adults and pediatric patients aged 2 years or older requiring supplemental oxygen, invasive mechanical ventilation, or extracorporeal membrane oxygenation.
Interrupting the cytokine outbreak
Baricitinib has the potential to reduce or interrupt the passage of SARS-CoV-2 into cells, and thus to inhibit the JAK1- and JAK2-mediated cytokine outbreak, researcher Heinz-Josef Lenz, MD , professor of medicine and preventive medicine at the University of Southern California’s Norris Comprehensive Cancer Center in Los Angeles, said in a comment. Baricitinib was also identified, using BenevolentAI’s proprietary, artificial intelligence-derived knowledge graph, as a numb-associated kinase inhibitor, with high affinity for AP2-associated protein kinase 1, an important endocytosis regulator.
Dr. Heinz-Josef Lenz
Early clinical data suggest a potent biologic effect of baricitinib 2 mg or 4 mg daily on circulating interleukin-6 levels and other inflammatory markers, including C-reactive protein. Dr. Lenz said the evidence for advantageous action of baricitinib on viral endocytosis and excessive cytokine release constitutes the rationale for using it in combination with other antivirals such as remdesivir in patients with moderate to severe COVID-19 illness.
“Although baricitinib may display antiviral activity on its own, its anti-inflammatory effects could hypothetically delay viral clearance,” Dr. Lenz added. “The data from Stebbing et al. confirm the dual actions of baricitinib, demonstrating its ability to inhibit viral entry into primary human hepatocyte spheroids and the reduction in inflammatory markers in COVID-19 patients.”
Other JAK inhibitors were not advanced as promising candidates for the research team’s attention by its artificial intelligence search, Dr. Stebbing noted. “The history of the pandemic has taught us the importance of well-designed observational studies as well as randomized, controlled trials. When it comes to COVID, pyrite looks much like gold, as failed studies of four antivirals have shown.”
Although the current translational research study did not use a placebo group, it is an important next step toward future randomized, controlled trials. “What’s great about this study is its high degree of collaboration, done with real urgency,” he added. “It’s harder to produce a paper that crosses multiple boundaries, like this one does, than a single-focused piece of work. But we wanted to link all of these threads together.”