Targeted failure of the week. Post No 27. Gemcitabine elaidate (also known as CO-101; CP-4126)

Shares in Clavis Pharma ASA (OSLO:CLAVIS) plummeted by more than 87 percent Monday following the failure of CO-101 (CP-4126) to demonstrate any impact on survival in a pivotal Phase II trial in metastatic pancreatic cancer.

CO-101 is a modified version of the nucleoside analogue gemcitabine, the standard treatment for pancreatic cancer. The addition of an elaidic acid lipid tail enables it to enter cells via passive diffusion instead of a transporter protein, called human equilibrative nucleoside transporter-1 (hENT1), which normally is required for gemcitabine transport and which is expressed at low levels in many pancreatic cancer patients.

The rationale underpinning the therapy was that the improved uptake and retention characteristics of CO-101 would translate into a survival benefit. However, there was no difference in survival between patients who received CO-101 and those who received gemcitabine. Each had a median survival of six months, regardless of their hENT1 status.

Well, I am a little bit sorry that Gemcitabine elaidate failed. The idea behind the drug was futile but interesting, not typical oversimplified “targeted” one. What targeted medicine will fail next?