On March 24, 2014 CytRx reported that it has initiated a pivotal global Phase 3 clinical trial (NCT02049905) to evaluate the efficacy and safety of aldoxorubicin as a second-line treatment for patients with soft tissue sarcoma (STS) under a Special Protocol Assessment with the FDA (Press release CytRx, MAR 24, 2014, View Source [SID:1234500318]). Aldoxorubicin combines the chemotherapeutic agent doxorubicin with a novel linker-molecule that binds specifically to albumin in the blood to allow for delivery of higher amounts of doxorubicin (3.5 to 4 times) without several of the major treatment-limiting toxicities seen with administration of doxorubicin alone.
This multicenter, randomized, open-label Phase 3 clinical trial is designed to enroll approximately 400 patients with metastatic, locally advanced or unresectable soft tissue sarcomas who have either not responded to, or have progressed following treatment with, one or more systemic regimens of non-adjuvant chemotherapies. Trial patients will be randomized 1:1 to be treated with aldoxorubicin or the investigator’s choice of an approved chemotherapeutic regimen, including doxorubicin, ifosfamide dacarbazine, pazopanib (Votrient), or gemcitabine plus docetaxel, with up to three comparator regimens to be selected by the investigator at each clinical site. The primary endpoint of the study is progression-free survival (PFS), and secondary endpoints include overall survival, response rates and safety. In January 2014, the Company announced it has received approval from the FDA to amend the Phase 3 protocol to continue dosing patients with aldoxorubicin until disease progression (defined as an increase in the size of measurable tumors by 20% or the development of a new tumor lesion), which creates the potential for substantially improved Phase 3 efficacy results. The Company expects to complete trial enrollment in 2015.
Following discussions with the FDA, the Phase 3 protocol has been agreed upon under a Special Protocol Assessment (SPA). As part of that assessment, the FDA agreed that the design and planned analysis of the study adequately addresses the objectives necessary to support a regulatory submission for approval.
The clinical trial will be conducted at approximately 100 clinical sites in the U.S., Europe, Canada, Latin America, Asia Pacific and Australia.