By Brady Huggett

Introgen Therapeutics Inc. reported Phase II data on its product, INGN 201, and preclinical findings for INGN 241 and INGN 251 at the 4th annual meeting of the American Society of Gene Therapy in Seattle.

Data were presented from 190 patients treated with INGN 201, Introgen¿s replication-impaired adenoviral vector carrying the human p53 suppressor gene. The study analyzed vector DNA recovered from samples taken from study subjects at various time points after treatment, and showed INGN 201 was genetically stable. Also, no horizontal transmission was documented in more than 400 samples from household members of the patients treated.

INGN 241, Introgen¿s adenoviral vector encoding the mda-7 gene, showed in preclinical studies it can inhibit cell growth in multiple tumor types when used alone or in combination with established therapies, Introgen said. The data were presented in three studies.

Two separate presentations on INGN 251, Introgen¿s adenoviral vector with the PTEN tumor suppressor gene, showed positive results, the company said. In the first study, INGN 251 was delivered to human melanoma cancer cells, after which apoptosis was observed. The second study, in which two in vitro models using endothelial cells tested the effects of INGN 251 on angiogenesis, also showed positive results. The first model showed a reduction in migration of human umbilical vein endothelial cells and the second model demonstrated an inhibition of formation of the blood-supply structures.

In other news from the meeting:

¿ Avigen Inc., of Alameda, Calif., said a second clinical trial of its gene therapy for hemophilia B received FDA approval. Patients enrolled in the trial will receive Avigen¿s adeno-associated virus gene therapy product, Coagulin B, via infusion into a liver artery. The first trial, which has enrolled eight patients, delivers the gene via intramuscular injection. The Phase I/II trial will be conducted at The Children¿s Hospital of Philadelphia and Stanford University Medical Center.

¿ Cell Genesys Inc., of Foster City, Calif., said interim results from its multicenter Phase I/II GVAX lung cancer vaccine trial, presented at the American Society of Clinical Oncology in May, also were presented at the Gene Therapy meeting. The data showed GVAX demonstrated evidence of antitumor activity, including a major response rate of 18 percent in patients with advanced non-small-cell lung cancer who failed chemotherapy and/or radiation therapy. (See BioWorld Today, May 15, 2001.)

¿ Chromos Molecular Systems Inc., of Burnaby, British Columbia, presented data describing the development of a chromosome-based platform technology that reduces the time to make product-specific artificial chromosome expression systems. The platform permits the placement of selected genes or genomic sequences onto the platform chromosome in a flexible manner and potentially allows for gene delivery and expression of large genes or multiple gene targets, the company said.

¿ Enzo Biochem Inc., of Farmingdale, N.Y., reported the continued expression of anti-HIV antisense RNA in T4 cells in the follow-up phase of its clinical trial. The data showed these cells expressed the antisense RNA for as long as 21 months to date. The results demonstrated long-term survival and functioning of antisense RNA in white blood cells and in CD4+ cells (T4 cells). Based on the results, Enzo said it will initiate a Phase II trial as well as expanding the Phase I trial.

¿ Titan Pharmaceuticals Inc., of South San Francisco, reported results on its product, RB94, a modified version of the retinoblastoma gene and a potential treatment for several cancers, including head and neck squamous cell carcinoma, and pancreatic cancer. The two preclinical studies showed the product had the ability to arrest growth and induce apoptosis in animal models using human tumor cells, Titan said.

¿ Valentis Inc., of Burlingame, Calif., reported interim results from a Phase IIb trial of its interleukin-2 gene medicine. The data show a positive trend for the group receiving the IL-2 gene therapy and chemotherapy, as compared to the chemotherapy only group. The median time to progression was 93 days for patients receiving only chemotherapy, as opposed to 129 days for those receiving chemotherapy and the IL-2 medicine. The treatments were injected directly into tumors of patients with Stage III and Stage IV carcinoma of the head and neck. The trial was conducted at 14 sites in Germany, the Czech Republic and Russia and enrolled 80 patients.