|Systematic (IUPAC) name|
1-((1S,3aR,14bS)-2-Methoxy-1,5,6,8,9,14b-hexahydro-4H-cyclopenta(a)(1,3)dioxolo(4,5-h)pyrrolo(2,1-b)(3)benzazepin-1-yl) 4-methyl (2R)-2-hydroxy-2-(4-hydroxy-4-methylpentyl)butanedioate
|Subcutaneous, intravenous infusion|
|Metabolism||Mostly via plasma esterases|
|Biological half-life||6 hours|
|Excretion||Urine (≤15% unchanged)|
|ATC code||L01XX40 (WHO)|
|Molar mass||545.62 g/mol|
Omacetaxine mepesuccinate (INN, trade names Synribo or Myelostat ), formerly named as homoharringtonine or HHT, is a pharmaceutical drug substance that is indicated for treatment of chronic myeloid leukemia (CML). It is a natural product first discovered in Cephalotaxus harringtonia, now manufactured by hemi-synthesis. It was approved by the US FDA in October 2012 for the treatment of adult patients with CML with resistance and/or intolerance to two or more tyrosine kinase inhibitors (TKIs).
In June 2009, results of a long-term open label Phase II study were published, which investigated the use of omacetaxine infusions in CML patients. After twelve months of treatment, about one third of patients showed a cytogenetic response. A study in patients who had failed imatinib and who had the drug resistant T315I mutation achieved cytogenetic response in 28% of patients and hematologic response in 80% of patients, according to preliminary data.
Phase I studies including a small number of patients have shown benefit in treating myelodysplastic syndrome (MDS, 25 patients) and acute myelogenous leukaemia (AML, 76 patients). Patients with solid tumors did not benefit from omacetaxine.
Common (1-10% frequency):
- GI haemorrhages
Mechanism of action
Omacetaxine is a protein translation inhibitor. It inhibits protein translation by preventing the initial elongation step of protein synthesis. It interacts with the ribosomal A-site and prevents the correct positioning of amino acid side chains of incoming aminoacyl-tRNAs. Omacetaxine acts only on the initial step of protein translation and does not inhibit protein synthesis from mRNAs that have already commenced translation.
- "Synribo (omacetaxine) dosing, indications, interactions, adverse effects, and more". Medscape Reference. WebMD. Retrieved 18 February 2014.
- "SYNRIBO (omacetaxine mepesuccinate) injection, powder, lyophilized, for solution [Cephalon, Inc.]". DailyMed. Cephalon, Inc. October 2012. Retrieved 18 February 2014.
- Sweetman, S, ed. (14 November 2012). "Omacetaxine Mepesuccinate". Martindale: The Complete Drug Reference. Medicines Complete (Pharmaceutical Press).
- Lacroix, Marc (2014). Targeted Therapies in Cancer. Hauppauge , NY: Nova Sciences Publishers. ISBN 978-1-63321-687-7.
- Li, Y. F.; Deng, Z. K.; Xuan, H. B.; Zhu, J. B.; Ding, B. H.; Liu, X. N.; Chen, B. A. (2009). "Prolonged chronic phase in chronic myelogenous leukemia after homoharringtonine therapy". Chinese medical journal 122 (12): 1413–1417. PMID 19567163.
- Quintás-Cardama, A.; Kantarjian, H.; Cortes, J. (2009). "Homoharringtonine, omacetaxine mepesuccinate, and chronic myeloid leukemia circa 2009". Cancer 115 (23): 5382–5393. doi:10.1002/cncr.24601. PMID 19739234.
- Wu, L.; Li, X.; Su, J.; Chang, C.; He, Q.; Zhang, X.; Xu, L.; Song, L.; Pu, Q. (2009). "Effect of low-dose cytarabine, homoharringtonine and granulocyte colony-stimulating factor priming regimen on patients with advanced myelodysplastic syndrome or acute myeloid leukemia transformed from myelodysplastic syndrome". Leukemia & Lymphoma 50 (9): 1461–7. doi:10.1080/10428190903096719. PMID 19672772.
- Gu, L. F.; Zhang, W. G.; Wang, F. X.; Cao, X. M.; Chen, Y. X.; He, A. L.; Liu, J.; Ma, X. R. (2010). "Low dose of homoharringtonine and cytarabine combined with granulocyte colony-stimulating factor priming on the outcome of relapsed or refractory acute myeloid leukemia". Journal of Cancer Research and Clinical Oncology 137 (6): 997–1003. doi:10.1007/s00432-010-0947-z. PMID 21152934.
- Kantarjian, H. M.; Talpaz, M.; Santini, V.; Murgo, A.; Cheson, B.; O'Brien, S. M. (2001). "Homoharringtonine". Cancer 92 (6): 1591–1605. doi:10.1002/1097-0142(20010915)92:6<1591::AID-CNCR1485>3.0.CO;2-U. PMID 11745238.
- Wetzler M, Segal D. Omacetaxine as an Anticancer Therapeutic: What is Old is New Again. Current Pharmaceutical Design 2011;17:59-64