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[lucid]

Geron has 2 drugs currently in phase I & II trials
GRNVAC1

GRNVAC1 is a therapeutic cancer vaccine comprised of autologous dendritic cells loaded ex vivo with telomerase mRNA. In March 2005, results of the first completed Phase 1-2 clinical trial of GRNVAC1 in metastatic prostate cancer patients was published in the Journal of Immunology (JI, 2005, 174:3798-38097). The vaccine was well tolerated with no major treatment-related toxicities. In addition, telomerase specific T-cell responses were generated in 19 of 20 subjects and vaccination was associated with a statistically significant increase in PSA doubling time and clearance of prostate cancer cells from the patients’ blood, indicative of potential clinical response. The telomerase vaccine is currently in multiple Phase 1-2 trials at Duke University where different strategies to optimize vaccine performance are under evaluation.

GRN163L

The new data on the effects of combination chemotherapy with GRN163L in multiple myeloma were derived from collaborative studies between Geron scientists and Dr. Malcolm Moore at the Memorial Sloan Kettering Cancer Center in New York. The results were presented by Robert Tressler, Ph.D., Geron’s executive director of preclinical drug development, in an invited talk at the symposium “Telomeres and Telomerase in Cancer”, and separately in greater detail at a poster session on “Senescence” by Server Ertam, a graduate student in Dr. Moore’s laboratory. The studies were conducted in immune compromised mice that were injected subcutaneously with an aggressive tumor line of human multiple myeloma. Animals were treated with i) a control solution (PBS), ii) GRN163L alone, iii) VELCADE© alone or iv) both GRN163L and VELCADE©. The results showed that relative to the control group, tumor growth was reduced 30% by GRN163L alone (p <.001) and 68% by the GRN163L and VELCADE© combination (p <.001). VELCADE© alone had no efficacy in this model at the dose used. All treatments were well tolerated.

This may be older news (2005 ish), but I found it very interesting.

[pyre]

I've heard about Geron's cancer drugs before, and I am a huge supporter of the company. I know that since Michael West's founding of the company they've been trying to utilize a Telomerase Inhibitor and an anti-tumor treatment (GRN163L), but the other drug (GRNVAC1) worries me more than a little.

Autologous dendritic cells loaded ex vivo with telomerase mRNA. No doubt they are targeting an autoimmune response to hTERT+ cells. The reason this worries me is that more than just cancer cells are hTERT+, including multiple varieties of stem cells and (less importantly) germ cells. In trials of the drug in mice, how could this therapy have succeeded, since so many murine somatic cells express mTR? In humans, has there been any investigation in to the manner in which the stem cells are placed in danger.

Of course, it is perfectly cool if it just Works. I am not convinced by the biology, though. The main method I can see them addressing this problem is by very selectively subjecting tissues to this autoimmune response, and then by avoiding contact with stem cells, forcing the T cell response to be confined to the cancer-containing tissue... I am skeptical at their ability to do that, though.

Can anyone set me right and explain how this works to me?