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Biotech / Medical : Hybridon HYBN, for discussion of antisense drugs. -- Ignore unavailable to you. Want to Upgrade?

To: Louis XIX who wrote (22)	1/22/1998 5:07:00 PM
From: JMarcus	Read Replies (1) \| Respond to of 42

Other antisense companies include Enzo Biochem (ENZ), AntiVirals (AVII), and Genta (GNTA). Genta calls its technology "anticode," but it is the same thing. Sequana (now part of Axyx Pharm (AXPH)) had also announced plans to develop antisense drugs. Isis (ISIP, not ISIS) is the leading antisense biotech company.

To: Louis XIX who wrote (22)	1/29/1998 8:25:00 PM
From: JMarcus	Read Replies (1) \| Respond to of 42

The following article mentions two more antisense companies (both from Canada): Inex Pharm. and Novopharm: biz.yahoo.com Wednesday January 28, 9:48 pm Eastern Time Antisense gene approach works from AIDS to cancer By Maggie Fox, Health and Science Correspondent WASHINGTON, Jan 28 (Reuters) - A gene therapy approach known as ''antisense'' may work against the virus that causes AIDS, as well as fight cancer and heart disease, three teams of researchers reported on Wednesday. The technique, which uses mirror-image molecules to interfere with undesirable genes, is gaining popularity among researchers trying out gene therapy. U.S. government researchers tested their technique in monkeys infected with SIV, the simian version of the deadly virus, and found it could help boost the immune system. Dr. Richard Morgan and colleagues at the National Human Genome Research Institute, the National Heart, Lung and Blood Institute and Johns Hopkins University tried to interrupt HIV's attack against immune system cells known as CD4 cells. HIV attacks CD4 cells, and to help itself replicate inside the cells it makes two proteins called Tat and Rev. This virus uses RNA rather than DNA in its replication. What Morgan's team did was put antisense Tat and Rev RNA into CD4 cells from three monkeys and then put the cells back into the monkeys. They then infected these monkeys with SIV, and also infected three other monkeys. The antisense genes started turning out mirror-image RNA, which connected to the HIV's RNA and stopped it from working correctly, they reported in the journal Nature Medicine. All six monkeys became infected, but the three who got the antisense therapy did not get sick and had lower levels of the virus in their blood and lymph nodes. ''It stops those two proteins, Tat and Rev, from being produced,'' Morgan said in a telephone interview. ''Without those the SIV virus cannot grow, cannot replicate.'' The next step is to try the technique in animals that already are infected with SIV, to see if it works. Morgan's team and several other groups are also trying antisense techniques in people infected with HIV. Morgan said it would only take about 10 percent of a patient's CD4 cells to have an effect. The cells are taken out, treated and then reinfused. ''This is just like a blood transfusion,'' Morgan said. ''To avoid immune rejection, you'd want to do the animal or patient's own cells.'' Because CD4 cells eventually die, the infusions would have to be repeated several times a year, Morgan said. Two other teams reported using similar techniques against cancer and breast cancer on Wednesday. Burkhard Jansen of the University of Vienna in Austria and colleagues, working with San Diego-based Genta Inc (GNTA - news), used an antisense molecule to counteract the effects of the bcl-2 gene, which stops a natural cell self-destruct program called apoptosis. Tumors are made up of cells that fail to die and instead reproduce out of control. Tumor cells that were injected with the bcl-2 antisense molecule and then treated with cancer drugs died at four times the rate of cells that got the drugs alone, Jansen reported in Nature Medicine. Another team from Brigham and Women's Hospital in Boston found that a similar antisense molecule targeted against the bcl-XL gene, another gene that regulates apoptosis, stimulated apoptosis in rabbit arteries. The therapy might be used to destroy the lesions that can arise after angioplasty used to stretch out clogged blood vessels. Other companies have already seen the potential in this approach. Vancouver-based Inex Pharma (IEX.TO - news) is also experimenting with antisense, as are Toronto-based Novopharm (NVO.TO - news) Bio and California-based Isis (ISIP - news). More Quotes and News: Genta Inc (Nasdaq:GNTA - news) Inex Pharmaceuticals Inc (Toronto:IEX.TO - news) ISIS Pharmaceuticals Inc (Nasdaq:ISIP - news) Novopharm Biotech Inc (Toronto:NVO.TO - news)