Relationship between response to lusutrombopag and splenic volume

Abstract

Aim: To assess the correlation between the efficacy of lusutrombopag and clinical characteristics in patients with chronic liver disease.

Methods: In this retrospective, multicenter study, which conducted at four locations in Japan, 50 thrombocytopenic patients with chronic liver disease were enrolled. All patients received oral lusutrombopag (3.0 mg/d for 7 d) for chronic liver disease. We assessed the increase in platelet count after the trial drug administration. A treatment response was defined as a platelet count ≥ 5 × 10⁴/μL and an increased platelet count ≥ 2 × 10⁴/μL from baseline after drug administration. We evaluated the response to lusutrombopag compared to baseline clinical characteristics in patients with chronic liver disease.

Results: The numbers of responders and non-responders were 40 (80.0%) and 10 (20.0%), respectively. The patients were divided into a responder and non-responder group, and we added factors that may correspond to successful treatment with lusutrombopag. Splenic volume and body weight were lower in the responder group than in the non-responder group. White blood cell count and hemoglobin level were higher in responders compared with non-responders. Using a logistic regression model to assess the relationship between response to lusutrombopag and clinical characteristics, multivariate analysis confirmed that splenic volume was an independent factor that predicted the response of platelet counts (P = 0.025; odds ratio = 11.2; 95% confidence interval: 1.354-103.0). Splenic volume negatively correlated to changes in platelet count (r = -0.524, P = 0.001).

Conclusion: Splenic volume influences the change in platelet counts after administration of lusutrombopag in patients with chronic liver disease.

Keywords: Lusutrombopag; Portal hypertension; Splenic volume; Thrombocytopenia; Thrombopoietin receptor agonist.

Figure 1

Axial computed tomography section (A) and reconstructed 3-D image (B) of the spleen. The volume measurement was performed using virtual organ computer-aided analysis on enhanced computed tomography in an enrolled patient with splenomegaly. The total volume was 1212 mL calculated using the software.

Figure 2

Mean changes in platelet count in all patients with splenomegaly treated with 3.0 mg/d lusutrombopag for 7 d. Data are expressed as the mean ± SD. The paired t-test was used to compare paired data. Max: The maximum count.

Figure 3

Correlation between change in platelet count and splenic size in patients with cirrhosis. Correlation was determined using Pearson’s r coefficient. Data are expressed as the mean ± SD.

Figure 4

Receiver-operating characteristic curve for splenic size and the area under the curve.