Platelet transfusion is used to prevent hemorrhagic events in patients with thrombocytopenia undergoing invasive procedures, but there are many disadvantages. We evaluated the efficacy and safety of lusutrombopag in patients with chronic liver disease and thrombocytopenia undergoing invasive procedures.

We performed a double-blind, parallel-group, phase 3 study of 96 patients with chronic liver disease and thrombocytopenia (platelet counts below 50,000/μL) undergoing invasive procedures from October 2013 to May 2014 at 81 centers in Japan. Patients were randomly assigned (1:1) to groups given once-daily lusutrombopag (3 mg) or placebo for up to 7 days. The primary efficacy endpoint was the proportion of patients not requiring platelet transfusion before the invasive procedure. The protocol-defined response (platelet count 50,000/μL or more with an increase of 20,000/μL or more from baseline) and the time course of the change in platelet count were also evaluated. Adverse events were recorded.

The proportions of patients who did not require preoperative platelet transfusion were 79.2% (38/48) in the lusutrombopag group and 12.5% (6/48) in the placebo group (P < .0001). A response was observed in 77.1% (37/48) of patients in the lusutrombopag group and 6.3% (3/48) of patients in the placebo group (P < .0001). In the lusutrombopag group without platelet transfusion, the median platelet count was 50,000/μL or more after 5 days; the mean time to reach the maximum platelet count was 13.4 days; and the number of days (adjusted mean) during which the platelet count was 50,000/μL or more was 21.09 days. Adverse drug reactions were reported in 8.3% of patients in the lusutrombopag group and 2.1% of patients in the placebo group. Two patients (1 per group) had a thrombotic event, but neither were associated with an excessive increase in platelet count (200,000/μL or more).

In a placebo-controlled trial, lusutrombopag was effective in achieving and maintaining the target platelet count in patients with chronic liver disease and thrombocytopenia undergoing invasive procedures. No significant safety concerns were raised. Japanese clinical trial registration no: JapicCTI-132323.