Silence Therapeutics said this week that it has identified the maximum tolerated dose for its siRNA-based cancer treatment Atu027 and that the drug has proven safe and well-tolerated in a nearly complete phase I trial.
The company also disclosed that it is in “advanced discussions” to raise between £4 million and £5 million ($6.2 million and $7.7 million) from new and existing shareholders. In March, Silence revealed that its cash runway extends only into the third quarter (GSN 3/22/2012).
Atu027 is a blunt-ended siRNA targeting the protein kinase PKN-3, which is associated with cellular morphology and locomotion in endothelial and cancer cells. In an open-label, dose-finding phase I trial, patients were enrolled to receive a total of 11 escalating doses of the drug.
According to Silence, enrollment of patients in the last cohort in dose level 10 has been completed, with the last treatment to occur later this month. Data from the study indicates that 0.336 mg/kg is the maximum tolerated dose of Atu027, and that treatment at dose level 8 — 0.18 mg/kg — achieved the same blood plasma siRNA concentration that in preclinical studies triggered PKN3 silencing.
“Therefore, the tested dose levels 8-10 can be considered effective and safe,” Silence said.
On the financial side, Silence said that should it raise the money from investors, it would have enough funds to support its operations until 2014.