Pixantrone

Pixantrone (rINN; trade name Pixuvri) is an experimental antineoplastic (anti-cancer) drug, an analogue of mitoxantrone with fewer toxic effects on cardiac tissue. It acts as a topoisomerase II poison and intercalating agent. The code name BBR 2778 refers to pixantrone dimaleate, the actual substance commonly used in clinical trials. Pixantrone (rINN; trade name Pixuvri) is an experimental antineoplastic (anti-cancer) drug, an analogue of mitoxantrone with fewer toxic effects on cardiac tissue. It acts as a topoisomerase II poison and intercalating agent. The code name BBR 2778 refers to pixantrone dimaleate, the actual substance commonly used in clinical trials. Anthracyclines are important chemotherapy agents. However, their use is associated with irreversible and cumulative heart damage. Investigators have attempted to design related drugs that maintain the biological activity, but do not possess the cardiotoxicity of the anthracyclines. Pixantrone was developed to reduce heart damage related to treatment while retaining efficacy. Random screening at the US National Cancer Institute of a vast number of compounds provided by the Allied Chemical Company led to the discovery of ametantrone as having significant anti-tumor activity. Further investigation regarding the rational development of analogs of ametantrone led to the synthesis of mitoxantrone, which also exhibited marked anti-tumor activity Mitoxantrone was considered as an analog of doxorubicin with less structural complexity but with a similar mode of action. In clinical studies, mitoxantrone was shown to be effective against numerous types of tumors with less toxic side effects than those resulting from doxorubicin therapy. However, mitoxantrone was not totally free of cardiotoxicity. A number of structurally modified analogs of mitoxantrone were synthesized and structure-activity relationship studies made. BBR 2778 was originally synthesized by University of Vermont researchers Miles P. Hacker and Paul A. Krapcho and initially characterized in vitro for tumor cell cytotoxicity and mechanism of action by studies at the Boehringer Mannheim Italia Research Center, Monza, and University of Vermont, Burlington. Other studies have been completed at the University of Texas M. D. Anderson Cancer Center, Houston, the Istituto Nazionale Tumori, Milan, and the University of Padua. In the search for novel heteroanalogs of anthracenediones, it was selected as the most promising compound. Toxicological studies indicated that BBR 2778 was not cardiotoxic, and US patents are held by the University of Vermont. An additional US patent application was completed in June 1995 by Boehringer Mannheim, Italy. Novuspharma, an Italian company, was established in 1998 following the merger of Boehringer Mannheim and Hoffmann-La Roche, and BBR 2778 was developed as Novuspharma's leading anti-cancer drug, pixantrone. A patent application for the injectable preparation was filed in May 2003. In 2003, Cell Therapeutics, a Seattle biotechnology company, acquired pixantrone through a merger with Novuspharma. Pixantrone is a substance that is being studied in the treatment of cancer. It belongs to the family of drugs called antitumor antibiotics. phase III clinical trials of pixantrone have been completed. Pixantrone is being studied as an antineoplastic for different kinds of cancer, including solid tumors and hematological malignancies such as non-Hodgkin lymphomas. Animal studies demonstrated that pixantrone does not worsen pre-existing heart muscle damage, suggesting that pixantrone may be useful in patients pretreated with anthracyclines. While only minimal cardiac changes are observed in mice given repeated cycles of pixantrone, 2 cycles of traditional anthracyclines doxorubicin or mitoxantrone result in marked or severe heart muscle degeneragion. Clinical trials substituting pixantrone for doxorubicin in standard first-line treatment of patients with aggressive non-Hodgkin's lymphoma, had a reduction in severe side effects when compared to patients treated with standard doxorubicin-based therapy. Despite pixantrone patients receiving more treatment cycles, a three-fold reduction in the incidence of severe heart damage was seen as well as clinically significant reductions in infections and thrombocytopenia, and a significant reduction in febrile neutropenia. These findings could have major implications for treating patients with breast cancer, lymphoma, and leukemia, where debilitating cardiac damage from doxorubicin might be prevented. Previous treatment options for multiply relapsed aggressive non-Hodgkin lymphoma had disappointing response rates. The completed phase II RAPID trial compared the CHOP-R regimen of Cyclophosphamide, Doxorubicin, Vincristine, Prednisone, and Rituximab to the same regimen, but substituting Doxorubicin with Pixantrone. The objective was to show that Pixantrone was not inferior to Doxorubicin and less toxic to the heart.