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Biotech / Medical : Biotech Valuation -- Ignore unavailable to you. Want to Upgrade?

To: aknahow who wrote (2719)	1/29/2001 8:52:57 PM
From: Jibacoa	Read Replies (1) \| Respond to of 52153

I am not familiar with Onyx, but have seen some reports of use of modified adenovirus in anti-tumor therapy as well as modified herpes virus and in some cases using an antiviral like Acyclovir afterwards. One that I recall was tried for prostate Ca was : Jpn J Cancer Res 2000 Dec;91(12):1339-1344 Oncolytic Viral Therapy for Human Prostate Cancer by Conditionally Replicating Herpes Simplex Virus 1 Vector G207. Oyama M, Ohigashi T, Hoshi M, Murai M, Uyemura K, Yazaki T Department of Physiology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. yazakit@med.keio.ac.jp Over the last few years, a conditionally replicating herpes simplex virus 1 (HSV-1) vector, G207 has been used for the treatment of several malignant tumors. In this article we evaluate the anti-tumoral effect of G207 against prostate cancer in vitro and in vivo. The susceptibility of the human prostate cancer cell lines, DU145 and PC3 to G207 at a multiplicity of infection (MOI) of 0.1 was examined. In addition, the growth characteristics of G207 were assessed. Athymic mice with s.c. tumors were inoculated in vivo intraneoplastically with 1 x 10(7) plaque-forming units (PFU) of G207. For the pathological analyses, s.c. tumors were stained with X-gal. DU145 and PC3 were efficiently destroyed by G207 within 7 days. The viral yields of G207 increased time-dependently. In vivo, the intraneoplastic inoculation of G207 induced a significant inhibition of the tumor growth. The mean tumor growth ratio was significantly inhibited in the G207-treated tumors (DU145, P < 0.0001; PC3, P < 0.001 versus controls). In a pathological study, many lacZ-positive cells were diffusely present in the G207-treated tumors. G207 showed a significant antitumoral effect against human prostate cancer cell lines, and thus may be considered a useful agent for the treatment of prostate cancer. Here is another one, also on prostate Ca: Prostate cancer gene therapy: herpes simplex virus thymidine kinase gene transduction followed by ganciclovir in mouse and human prostate cancer models. Eastham JA, Chen SH, Sehgal I, Yang G, Timme TL, Hall SJ, Woo SL, Thompson TC Matsunaga-Conte Prostate Cancer Research Center, Houston, TX, USA. Prostate cancer is the most common internal malignancy in men in the United States. Most cancers are diagnosed when they are locally advanced or metastatic and there is no effective treatment. In this study we evaluated the effectiveness of cytotoxic gene therapy in human PC-3 and DU145 prostate cancer cell lines and in a rodent cell line, RM-1, derived from the mouse prostate reconstitution model system. The cell lines were efficiently transduced in vitro by a replicative-defective recombinant adenovirus (ADV) carrying the herpes simplex virus thymidine kinase gene (HSV-tk). A virus titer-dependent sensitivity to ganciclovir (GCV) was observed. To determine a target therapeutic viral dose in vivo, subcutaneous tumors were generated by injection of RM-1 cells in syngeneic male hosts and injected with escalating doses of HSV-tk virus (5 x 10(7) to 1 x 10(9) pfu). The mice received GCV twice daily for 6 days and were sacrificed when tumor volumes exceeded 2.5 cm3 or when they appeared to be in distress. Because the two highest doses were equally as effective, further controlled studies were performed with the lower dose of 5 x 10(8) pfu with ADV/RSV-tk or a control virus containing the beta-galactosidase gene (ADV/RSV-beta-Gal) and treated with GCV or saline (PBS). The mean tumor volume in the treated animals was 16% that of control animals at 13 days. Histologically, treated tumors demonstrated necrosis and had a significantly higher apoptotic index. Survival data indicated that the treatment animals lived 7 days (21 in total) longer than the control animals, with 1 treatment animal being totally free of tumor. These results demonstrate that HSV-tk + GCV cytotoxic gene therapy can inhibit the growth of mouse and human prostate cancer cells in vitro and interrupt tumor growth of an aggressive mouse prostate cancer cell line in vivo

To: aknahow who wrote (2719)	1/29/2001 8:56:59 PM
From: Biomaven	Read Replies (2) \| Respond to of 52153

george, I've intermittently owned them in the past. My small stake went in my recent year-end tax selling (along with just about everything else I owned that showed even a small loss). The key mystery with their product has been why it also seemed to work in tumors without abnormal p53. This cast doubt on the whole rationale. This post may provide some explanation: Message 14492963 How does Xoma fit in here? I didn't know they were in the manufacturing business. Peter

To: aknahow who wrote (2719)	1/30/2001 6:29:44 AM
From: SnowShredder	Read Replies (2) \| Respond to of 52153

Hi George, The data that Onyx released in Aug 2000 was impressive, but I'm a little disappointed with the results of CI-1042 as a stand alone drug. The agreement with XOMA makes me think that they have confidence in their product, but on the other hand, if this product doesn't pan out, what else do they have in the pipe? and do they have the $ to take their pipe to market? BWDIK? If you're into replicating viruses check out Oncolytics Biotech (although I haven't figured out how to buy a Canadian biotech through my broker yet >gg<). Subject 31728 Best of Luck, WHG?