Ibrutinib-induced severe liver injury

Liver Pathology Related to Onco-Therapeutic Agents

Oncotherapeutic agents can cause a wide range of liver injuries from elevated liver functions tests to fulminant liver failure. In this review, we emphasize a newer generation of drugs including immune checkpoint inhibitors, protein kinase inhibitors, monoclonal antibodies, and hormonal therapy. A few conventional chemotherapy agents are also discussed.

Hepatotoxicity of Small Molecule Protein Kinase Inhibitors for Cancer

Small molecule protein kinase inhibitors (PKIs) have become an effective strategy for cancer patients. However, hepatotoxicity is a major safety concern of these drugs, since the majority are reported to increase transaminases, and few of them (Idelalisib, Lapatinib, Pazopanib, Pexidartinib, Ponatinib, Regorafenib, Sunitinib) have a boxed label warning. The exact rate of PKI-induced hepatoxicity is not well defined due to the fact that the majority of data arise from pre-registration or registration trials on fairly selected patients, and the post-marketing data are often based only on the most severe described cases, whereas most real practice studies do not include drug-related hepatotoxicity as an end point. Although these side effects are usually reversible by dose adjustment or therapy suspension, or by switching to an alternative PKI, and fatality is uncommon, all patients undergoing PKIs should be carefully pre-evaluated and monitored. The management of this complication requires an individually tailored reappraisal of the risk/benefit ratio, especially in patients who are responding to therapy. This review reports the currently available data on the risk and management of hepatotoxicity of all the approved PKIs.

Zanubrutinib-induced liver injury: a case report and literature review

BACKGROUND

Zanubrutinib is a Bruton's tyrosine kinase inhibitor that has been recently licensed in refractory mantle cell lymphoma and under assessment in phase 3 clinical trials for other B cell malignancies. To date, there are no reported cases of hepatotoxicity secondary to zanubrutinib. We report the first case of severe liver injury due to zanubrutinib.

CASE PRESENTATION

A 56-year-old Caucasian male with a history of relapsed lymphoplasmacytic lymphoma was admitted to the hospital with new-onset jaundice, choluria, and pruritus for 10 days. He had been on zanubrutinib as part of a clinical trial for 30 months. His blood profile showed a severe hepatocellular injury with jaundice (alanine transaminase 2474 IU/L and total bilirubin 141 umol/L with mild coagulopathy). He had an extensive work-up including virology, autoimmune, and metabolic profiles in addition to abdominal ultrasound with no alternative explanation found for his liver injury. Zanubrutinib-induced liver injury was suspected, and causality assessment by the updated Roussel Uclaf Causality Assessment Method score showed a probable causal relationship with zanubrutinib. His liver histology was also consistent with drug-induced liver injury. His liver biochemistry improved following cessation of zanubrutinib and normalised after 8 weeks.

CONCLUSION

We report the first case of severe liver injury secondary to zanubrutinib after 30 months of treatment. This case raises clinical awareness regarding zanubrutinib-induced liver toxicity and the importance of drug withdrawal in the event of liver injury.

Comparison of the drug-drug interactions potential of ibrutinib and acalabrutinib via inhibition of UDP-glucuronosyltransferase

Ibrutinib and acalabrutinib are two Bruton's tyrosine kinase (BTK) inhibitors which have gained Food and Drug Administration (FDA) approval for the treatment of various B cell malignancies. Herein, we investigated the effects of the two drugs on UDP-glucuronosyltransferase (UGT) activities to evaluate their potential risk for drug-drug interactions (DDIs) via UGT inhibition. Our data indicated that ibrutinib exerted broad inhibition on most of UGTs, including a potent competitive inhibition against UGT1A1 with a K_i value of 0.90 ± 0.03 μM, a noncompetitive inhibition against UGT1A3 and UGT1A7 with K_i values of 0.88 ± 0.03 μM and 2.52 ± 0.23 μM, respectively, while acalabrutinib only exhibited weak UGT inhibition towards all tested UGT isoforms. DDI risk prediction suggested that the inhibition against UGT1A1 and UGT1A3 by ibrutinib might bring a potential DDIs risk, while acalabrutinib was unlikely to trigger clinically significant UGT-mediated DDIs due to its weak effects. Our study raises an alarm bell about potential DDI risk associated with ibrutinib, however, the extrapolation from in vitro data to in vivo drug interactions should be taken with caution, and additional systemic study is needed.

Inhibition of complement C1s in patients with cold agglutinin disease: lessons learned from a named patient program

Cold agglutinin disease (CAD) causes predominantly extravascular hemolysis and anemia via complement activation. Sutimlimab is a novel humanized monoclonal antibody directed against classical pathway complement factor C1s. We aimed to evaluate the safety and efficacy of long-term maintenance treatment with sutimlimab in patients with CAD. Seven CAD patients treated with sutimlimab as part of a phase 1B study were transitioned to a named patient program. After a loading dose, patients received biweekly (once every 2 weeks) infusions of sutimlimab at various doses. When a patient's laboratory data showed signs of breakthrough hemolysis, the dose of sutimlimab was increased. Three patients started with a dose of 45 mg/kg, another 3 with 60 mg/kg, and 1 with a fixed dose of 5.5 g every other week. All CAD patients responded to re-treatment, and sutimlimab increased hemoglobin from a median initial level of 7.7 g/dL to a median peak of 12.5 g/dL (P = .016). Patients maintained near normal hemoglobin levels except for a few breakthrough events that were related to underdosing and which resolved after the appropriate dose increase. Four of the patients included were eventually treated with a biweekly 5.5 g fixed-dose regimen of sutimlimab. None of them had any breakthrough hemolysis. All patients remained transfusion free while receiving sutimlimab. There were no treatment-related serious adverse events. Overlapping treatment with erythropoietin, rituximab, or ibrutinib in individual patients was safe and did not cause untoward drug interactions. Long-term maintenance treatment with sutimlimab was safe, effectively inhibited hemolysis, and significantly increased hemoglobin levels in re-exposed, previously transfusion-dependent CAD patients.

Multikinase inhibitor-induced liver injury in patients with cancer: A review for clinicians

BACKGROUND

Multikinase inhibitors (MKI) are targeted molecular agents that have revolutionized cancer management. However, there is a paucity of data concerning MKI-related liver injury risk and clinical guidelines for the management of liver toxicity in patients receiving MKI for cancer are scarce.

DESIGN

We conducted a PubMed search of articles in English published from January 2000 to December 2018 related to hepatotoxicity of the 29 FDA-approved MKIs at doses used in clinical practice. The search terms were the international non-proprietary name of each agent cross-referenced with «hepatotoxicity», «hepatitis», «hepatic adverse event», or «liver failure», and «phase II clinical trial», «phase III clinical trial», or «case report».

RESULTS

Following this search, 140 relevant studies and 99 case reports were considered. Although asymptomatic elevation of aminotransferase levels has been frequently observed in MKI clinical trials, clinically significant hepatotoxicity is a rare event. In most cases, the interval between treatment initiation and the onset of liver injury is between one week and two months. Liver toxicity is often hepatocellular and less frequently mixed. Life-threatening MKI-induced hepatic injury has been described, involving fulminant liver failure or death. Starting from existing data, a description of MKI-related liver events, grading of hepatotoxicity risk, and recommendations for management are also given for various MKI molecules.

CONCLUSION

All MKIs can potentially cause liver injury, which is sometimes irreversible. As there is still no strategy available to prevent MKI-related hepatotoxicity, early detection remains crucial. The surveillance of liver function during treatment may help in the early detection of hepatotoxicity. Furthermore, the exclusion of potential causes of hepatic injury is essential to avoid unnecessary MKI withdrawal.

Severe Hepatotoxicity due to Ibrutinib with a Review of Published Cases

Ibrutinib, an irreversible Bruton's tyrosine kinase inhibitor, is an effective treatment for Waldenström's macroglobulinemia, chronic lymphocytic leukemia, and several other types of lymphoma. Studies prior to FDA approval in 2015 failed to demonstrate any hepatotoxicity. However, since then, there have been 2 reports in the literature of severe hepatic injury. We present a third case of a 77-year-old woman presenting with nausea and jaundice after recent discontinuation of ibrutinib and compare the presentation as well as course of all 3 known cases. The sudden onset of acute hepatotoxicity is idiosyncratic, occurring weeks after starting ibrutinib treatment. Liver biopsies in all cases revealed mixed hepatocellular and cholestatic features. Improvement progressed slowly upon discontinuation of ibrutinib. Awareness of ibrutinib hepatotoxicity, periodic surveillance of liver function tests, early recognition of any abnormalities, and prompt discontinuation of the medication are recommended.