Case report: Ensitrelvir for treatment of persistent COVID-19 in lymphoma patients: a report of two cases

Persistent COVID-19 is a well recognized issue of concern in patients with hematological malignancies. Such patients are not only at risk of mortality due to the infection itself, but are also at risk of suboptimal malignancy-related outcomes because of delays and terminations of chemotherapy. We report two lymphoma patients with heavily pretreated persistent COVID-19 in which ensitrelvir brought about radical changes in the clinical course leading to rapid remissions. Patient 1 was on ibrutinib treatment for mantle cell lymphoma when he developed COVID-19 pneumonia which was severe and ongoing for 2 months despite therapy with molnupiravir, multiple courses of remdesivir, one course of sotrovimab, tocilizumab, and steroids. Patient 2 was administered R-CHOP therapy for diffuse large B-cell lymphoma when he developed COVID-19 which was ongoing for a month despite treatment with multiple courses of remdesivir and one course of sotrovimab. A 5-day administration of ensitrelvir promptly resolved the persistent COVID-19 accommodated by negative conversions of RT-qPCR tests in both patients within days. Ensitrelvir is a novel COVID-19 therapeutic that accelerates viral clearance through inhibition of the main protease of SARS-CoV-2, 3-chymotrypsin-like protease, which is vital for viral replication. Ensitrelvir is a promising treatment approach for immunocompromised lymphoma patients suffering from persisting and severe COVID-19

Successful management of acute graft-versus-host disease with ibrutinib during cord blood transplantation for germline DDX41-mutated acute myeloid leukemia

Background: Acute graft-versus-host disease (GVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with significant morbidity and mortality, and efficacy of currently available therapeutics are limited. Acute and chronic GVHD are similar in that both are initiated by antigen presenting cells and activation of alloreactive B-cells and T-cells, subsequently leading to inflammation, tissue damage, and organ failure. One difference is that acute GVHD is mostly attributed to T-cell activation and cytokine release, whereas B-cells are the key players in chronic GVHD. Ibrutinib is an irreversible inhibitor of the Bruton's tyrosine kinase (BTK), which is part of B-cell receptor signaling. Ibrutinib is currently used for treating chronic GVHD, but its efficacy towards acute GVHD is unknown. Besides BTK, ibrutinib also inhibits interleukin-2 inducible T-cell kinase (ITK), which is predominantly expressed in T-cells and a crucial enzyme for activating the downstream pathway of TCR signaling. ITK activates PLCγ2 and facilitates signaling through NF-κB, NFAT, and MAPK, leading to activation and proliferation of T-cells and enhanced cytokine production. Therefore, the TCR signaling pathway is indispensable for development of acute GVHD, and ITK inhibition by ibrutinib would be a rational therapeutic approach. Case presentation: A 56-year-old male acute myeloid leukemia patient with Myeloid neoplasms with germline DEAD-box RNA helicase 41 (DDX41) mutation underwent cord blood transplantation and developed severe gastrointestinal (GI) acute GVHD which was refractory to steroids and mesenchymal stem cell therapy. While acute GVHD accommodated by multiple life-threatening GI bleeding events persisted, chronic cutaneous GVHD developed, and ibrutinib 420 mg/day was initiated from day 147 of transplant. Although ibrutinib was commenced targeting the chronic GVHD, unexpected and abrupt remission of acute GVHD along with remission of chronic GVHD was observed. Conclusion: Ibrutinib is a promising therapeutic for treating acute GVHD, and further studies are warranted