Oblimersen (INN, trade name Genasense; also known as Augmerosen and bcl-2 antisense oligodeoxynucleotide G3139) is an antisenseoligodeoxyribonucleotide being studied as a possible treatment for several types of cancer, including chronic lymphocytic leukemia, B-cell lymphoma, and breast cancer. It may kill cancer cells by blocking the production of Bcl-2—a protein that makes cancer cells live longer—and by making them more sensitive to chemotherapy.
The antisense oligonucleotide drug oblimersen was developed by Genta Incorporated to target Bcl-2. An antisense DNA or RNA strand is non-coding and complementary to the coding strand (which is the template for producing respectively RNA or protein). An antisense drug is a short sequence of RNA which hybridises with and inactivates mRNA, preventing the protein from being formed.[citation needed]
It was shown that the proliferation of human lymphomacells (with t(14;18) translocation) could be inhibited by antisense RNA targeted at the start codon region of Bcl-2 mRNA. In vitro studies led to the identification of oblimersen, which is complementary to the first 6 codons of Bcl-2 mRNA.[1]
These have shown successful results in Phase I/II trials for lymphoma, and a large Phase III trial was launched in 2004.[2]
By the first quarter 2010, the drug had not received FDA approval due to disappointing results in a melanoma trial. Although its safety and efficacy have not been established for any use, Genta Incorporated still[when?] claims on its website that studies are currently under way to examine the potential role of oblimersen in a variety of clinical indications.
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References
↑ Dias N, Stein CA (November 2002). "Potential roles of antisense oligonucleotides in cancer therapy. The example of Bcl-2 antisense oligonucleotides". European Journal of Pharmaceutics and Biopharmaceutics. 54 (3): 263–9. doi:10.1016/S0939-6411(02)00060-7. PMID12445555.
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