Is platelet monitoring during 7-day lusutrombopag treatment necessary in chronic liver disease patients with thrombocytopenia undergoing planned invasive procedures? A phase IIIb open-label study

Safety and effectiveness of lusutrombopag in patients who have chronic liver disease with thrombocytopenia and undergoing invasive procedures: Real-world post-marketing surveillance in Japan

AIM

Lustrombopag has been approved for the treatment of thrombocytopenia in patients with chronic liver diseases who are scheduled to undergo an invasive procedure. Here, we report the final results of a post-marketing surveillance assessing the safety and effectiveness of lusutrombopag in Japan.

METHODS

This multicenter, prospective, real-world surveillance collected data from case report forms between October 2016 and May 2021. The observation period was 2 months after the first day of lusutrombopag treatment. Safety and effectiveness (proportion of patients avoiding preoperative platelet transfusion and responders who achieved platelet count increase from baseline) were assessed.

RESULTS

The safety analysis set included 1033 (100.0%), 130 (12.6%), and 14 (1.4%) patients who received one or more, two or more, and three or more treatment cycle(s), and 482 (48.9%), 457 (46.3%), and 43 (4.4%) patients who were Child-Pugh class A, B, and C, respectively. The most common serious adverse drug reactions were portal vein thrombosis, pancytopenia, and white blood cell count decrease, reported in 14 (1.36%), three (0.29%), and two (0.19%) patients, respectively. The incidence of adverse drug reactions was not higher in patients with Child-Pugh class C or those undergoing retreatment cycles compared with other Child-Pugh classes or the first treatment cycle, respectively. During the observation period of the first treatment cycle, 94.7% (889/939) of patients avoided preoperative platelet transfusion and 82.8% (741/895) of the patients met the responder criteria.

CONCLUSIONS

This surveillance study further supports the safety and effectiveness of lusutrombopag in a broad range of patients with chronic liver diseases undergoing planned invasive procedures.

CLINICAL TRIAL REGISTRATION

JapicCTI-163432.

Pharmacokinetic Assessment and Treatment Effect of Lusutrombopag in Child-Pugh Class C Patients: Review of Patient Data from Two Clinical Studies and Post-Marketing Surveillance

INTRODUCTION

Patients with thrombocytopenia and chronic liver disease are at increased risk of bleeding during invasive procedures due to low platelet counts. Lusutrombopag, an orally active thrombopoietin receptor agonist, increases platelet count and reduces the need for platelet transfusion in chronic liver disease patients with thrombocytopenia undergoing a planned invasive procedure. The safety of lusutrombopag in patients with Child-Pugh class C chronic liver disease is not known. The present analysis was performed to determine the pharmacokinetics, efficacy, and safety of lusutrombopag in patients with Child-Pugh class C chronic liver disease.

METHODS

Data for patients with Child-Pugh class C chronic liver disease were collected from three data sets: a phase 1/2 Child-Pugh class C study (n = 5) (JapicCTI-163289 [Japan Pharmaceutical Information Center]), a phase 3 pivotal study (L-PLUS 2, n = 3) (NCT02389621 [Clinicaltrials.gov]), and ongoing post-marketing surveillance (n = 27) (JapicCTI-163432 [Japan Pharmaceutical Information Center]). Patients received lusutrombopag at 3 mg for up to 7 days. Safety and efficacy assessments were collected from two clinical studies and the post-marketing surveillance; pharmacokinetic data were collected from the phase 1/2 study.

RESULTS

Mean C_max and AUC_0-τ were lower in Child-Pugh class C patients than Child-Pugh class A and B; individual patients' C_max and AUC_0-τ values overlapped among Child-Pugh classes. In lusutrombopag patients who did not receive platelet transfusion (n = 4 in phase 1/2, n = 1 in phase 3, n = 24 in post-marketing surveillance), the median (range) maximum platelet count was 88.5 × 10⁹/L (54-105 × 10⁹/L), 80 × 10⁹/L, and 91 × 10⁹/L (41-186 × 10⁹/L; n = 23), respectively. There were no treatment-related adverse events or treatment-related serious adverse events. One patient from the phase 1/2 study had a non-serious portal vein thrombosis, which was not considered treatment-related.

CONCLUSIONS

The analysis presented in this study suggests that lusutrombopag increases platelet counts in Child-Pugh class C patients and is safe and well tolerated in this patient population.

TRIAL REGISTRATION

L-PLUS 2: NCT02389621 (Clinicaltrials.gov). Phase 1/2: JapicCTI-163289 (Japan Pharmaceutical Information Center [JAPIC]). Post-marketing surveillance: JapicCTI-163432 (JAPIC).

Treatment algorithm for thrombocytopenia in patients with chronic liver disease undergoing planned invasive procedures

Thrombocytopenia is highly prevalent in patients with chronic liver disease (CLD) and these patients often require invasive procedures that carry a risk of bleeding. To prevent bleeding, guidelines recommend increasing platelet counts in patients with CLD who have thrombocytopenia and are planned to undergo invasive procedures. There are currently two options to increase platelet counts in patients in this setting: platelet transfusion or thrombopoietin receptor agonists (TPORAs). Several treatment algorithms have been developed in the US to help physicians choose the best course of treatment for each patient; however, to date, no such algorithm has been proposed in other countries, where the choice of treatment has been based on each physician's judgment and experience. Here, we discuss the pathogenesis and treatment of thrombocytopenia in patients with CLD, we review and present current evidence of the efficacy of TPORAs for the treatment of thrombocytopenia in patients with CLD, and we present our expert opinion on a Japanese treatment algorithm for thrombocytopenia in patients with CLD who are planned to undergo invasive procedures. This algorithm aims to provide guidance for optimal decision making in the selection of TPORA therapy or platelet transfusion based on the latest evidence and according to actual clinical practice.