Selinexor in Advanced Liposarcoma

Inclusion Criteria:

1. Patients ≥12 years of age
2. Body surface area (BSA) ≥ 1.2 m2
3. Histologic evidence of DDLS at any time prior to randomization AND current evidence ofDDLS requiring treatment
4. Must have measurable disease per RECIST v1.1 Response Criteria
5. Radiologic evidence of disease progression within 6 months prior to randomization. Ifthe patient received other intervening therapy after documented disease progression,further disease progression must be documented after the completion of the interveningtherapy
6. Must have had at least 2 prior lines of systemic therapy for liposarcoma (not toexceed 5 prior lines)
7. If patient received any previous systemic therapy, the last dose must have been ≥ 21days prior to randomization (or ≥ 5 half-lives of that drug, whichever is shorter)with all clinically significant therapy-related toxicities having resolved to ≤ Grade 1

Exclusion Criteria:

1. Patients with pure well-differentiated liposarcoma (WDLS), myxoid/round cell orpleomorphic tumor histologic subtypes
2. Known active hepatitis B (HepB), hepatitis C (HepC) or human immunodeficiency virus (HIV) infection
3. Known central nervous system metastases