A phase Ib study of ribociclib in combination with doxorubicin in advanced soft tissue sarcomas (aSTS).
Abstract No : 11548
Abstract Type : Poster session
Indication : Soft Tissue Sarcoma
Intervention : ribociclib + doxorubicin
Company : Novartis
Technology : Small molecule
9 screened pts were ineligible by Rb status. 16 pts enrolled with 15 evaluable for dose determination (7 dedifferentiated LPS, 8 other subtypes). 4 of 7 pts treated at starting dose level (400 mg ribo, 75 mg/ m2 dox) had a DLT; all febrile neutropenia. 1 of 8 pts treated at dose level -1 (400 mg ribo, 60 mg/m2 dox) had a DLT of gr4 anemia. Febrile neutropenia events occurred during cycle 1, when growth factors were prohibited. Toxicity was similar to historical dox AEs (Table). Two partial responses for overall response rate (ORR) of 13%. Five (33%) were progression-free at 18 wks. Correlative studies ongoing
This study determined a RP2D of ribo 400 mg with dox 60 mg/m2 when used in combination for the treatment of aSTS.
Safety and tolerability of the combination is on par with adverese events expected with single agent doxorubicin.