Combination of anti-CD20 and hetrombopag in relapsed/refractory immune thrombocytopenia: a case series

This study aimed to assess the effectiveness of anti-CD20 monoclonal antibody and hetrombopag for relapsed/refractory immune thrombocytopenia (ITP) following glucocorticoid treatment.

We retrospectively included four patients with relapsed/refractory ITP. The median disease duration is 9 months. Their prior lines of therapy numbered 4, 2, 4, and 2, respectively. They were treated with a combination of anti-CD20 monoclonal antibody and hetrombopag, followed by maintenance therapy with hetrombopag and monitoring of platelet (PLT) changes.

All four patients achieved complete response (CR), with the time to response ranging from 2 to 9 days and the duration of response (DoR) ranging from 3 to 27 months. CR was defined as a PLT count >100 × 10⁹/L and the absence of bleeding. The treatment was well tolerated. Only the first patient's PLT count decreased to 31 × 10⁹/L following discontinuation of therapy after 6 months of DoR. Accordingly, the patient was treated with avatrombopag monotherapy, which maintained the PLT count at normal levels. The third patient presented with secondary ITP. After treatment with ripertamab-hetrombopag, the patient received combination therapy with hetrombopag, glucocorticoids, tacrolimus, and hydroxychloroquine, with the PLT count being maintained within the normal range. The other two patients remained in sustained CR throughout the follow-up period.

Combining anti-CD20 monoclonal antibody with hetrombopag may offer therapeutic benefits in patients with relapsed/refractory ITP.