Cytrx’s tamibarotene achieves molecular complete remission in advanced acute promyelocytic leukemia

Jul 23 2010

CytRx Corporation (NASDAQ: CYTR), a biopharmaceutical company specializing in oncology, today announced that a 44-year-old female patient with advanced acute promyelocytic leukemia (APL) achieved molecular complete remission with no evidence of disease in the blood cells and/or bone marrow following treatment with CytRx's oncology drug candidate tamibarotene. The patient was treated in CytRx's Phase 2 STAR-1 registration trial, which is evaluating the efficacy and safety of orally available tamibarotene as a third-line treatment for APL. The patient report, "Molecular remission in advanced acute promyelocytic leukaemia after treatment with the oral synthetic retinoid Tamibarotene," (Francesco Lo-Coco, et. al.), was published in the July online issue of the peer-reviewed British Journal of Haematology with publication in the print edition expected later this year.

“Molecular remission in advanced acute promyelocytic leukaemia after treatment with the oral synthetic retinoid Tamibarotene”

"This event represents a very significant milestone for CytRx and our drug candidate tamibarotene. Tamibarotene has saved a life and nothing can compare with that," said CytRx President and CEO Steven A. Kriegsman. "These important results indicate that tamibarotene warrants further evaluation as a third-line treatment and in combination as a first-line treatment for APL. We are also considering developing tamibarotene for other cancers as well.

"Previously published reports indicate that tamibarotene is 10-times more potent and may be better tolerated than all trans retinoic acid (ATRA). We believe that the combination of tamibarotene and arsenic trioxide (ATO) could produce a complete response rate similar to the ATRA and ATO combination with fewer toxicities such as APL differentiation syndrome. We currently are conducting a dose escalation trial combining tamibarotene with ATO as an important step in our ultimate goal of evaluating tamibarotene as a first-line treatment for APL," he added.

CytRx Chief Medical Officer Daniel Levitt, M.D., Ph.D., stated, "This demonstrates that orally administered tamibarotene is active in APL patients relapsing after treatment with ATRA, anthracyclines, and ATO, the current first and second-line treatments, and a bone marrow transplant." In addition to maintaining a complete remission six months following the last dose, tamibarotene was also well tolerated. This patient reportedly had a severe toxic reaction called APL differentiation syndrome when given ATRA. However, when tamibarotene was administered, the patient achieved a molecular complete remission without these side effects."

The APL patient profiled in the peer-reviewed British Journal of Haematology article was initially treated simultaneously with ATRA and chemotherapy. Following treatment she achieved molecular complete remission, although she developed severe APL differentiation syndrome. During the subsequent two years, she received maintenance therapy and then suffered an APL relapse. She was treated with a combination therapy of ATRA and ATO, and again achieved molecular complete remission. She then underwent a bone marrow transplant, at which time molecular complete remission was confirmed. However, her APL relapsed again. The patient was then enrolled in CytRx's STAR-1 registration trial and treated with tamibarotene for 56 days at the Department of Biopathology at the University of Rome 'Tor Vergata'. A molecular complete remission in the bone marrow was documented at the end of the treatment period and again six months following the last treatment with tamibarotene.