Tekmira Pharmaceuticals this week provided a minor update on its ongoing research and development efforts, highlighting its phase I cancer drug TKM-PLK1, which is slated to enter phase II testing later this year, and its Ebola infection treatment TKM-Ebola, which is being readied for a new phase I study before year-end.
During a presentation at this year's Biotechnology Industry Organization's BIO-CEO event this week, Tekmira President and CEO Mark Murray also hinted that the company was looking to expand beyond its core human therapeutics focus, noting that the firm is evaluating the use of its lipid nanoparticle-based siRNA delivery vehicles for use in agriculture applications.
As reported by Gene Silencing News, a number of ag-bio players have been increasingly looking to use RNAi within their offerings, including Monsanto, which recently disclosed that it was advancing four RNAi products through its pipeline (GSN 1/17/2013) and inked a technology-licensing deal with Alnylam Pharmaceuticals late last year (GSN 9/6/2012).
Murray, however, did not comment further about the agricultural work and a company spokesperson said that no additional details were being provided.
Tekmira's lead drug candidate remains TKM-PLK1, an siRNA-based cancer drug targeting the cell cycle protein polo-like kinase 1 and formulated with the nanoparticle technology. Last summer, the company presented interim data from an ongoing phase I trial showing the agent to be well tolerated despite an “aggressive dosing regimen” (GSN 8/16/2012).
Murray said this week that enrollment in the phase I study continues with patients receiving a 0.75 mg/kg dose of the drug, and that additional data will be presented at this year's American Association of Cancer Research meeting in April.
Meantime, Tekmira is prepping for a planned phase II trial to launch in the second half of the year, and is weighing a variety of different cancer indications to focus on. These include carcinoid tumors, hepatocellular carcinoma, and colorectal cancer in patients carrying KRAS mutations.
He added that the firm is aiming to select an indication with high unmet medical need and, therefore, one that may offer an accelerated route toward clinical approval.
Coming up behind TKM-PLK1 is TKM-Ebola, which is being developed in collaboration with the Department of Defense. In 2010, the company received a $34.7 million, three-year contract through the agency's Transformational Medical Technologies program. The contract includes an option allowing the DoD to extend the arrangement through US Food and Drug Administration approval, which would result in roughly $140 million in funding to Tekmira.
Despite having moved into human testing, last August the DoD issued a temporary stop-work order on the program due to budgetary constraints. In October, the order was lifted and work resumed (GSN 10/4/2012).
Since then, Tekmira has asked the DoD to amend its contract so that it may tweak the drug candidate to use a more potent next-generation lipid nanoparticle. The company said that it aims to complete the formulation adjustments and submit them to the US Food and Drug Administration in the second half of this year in order to begin a new phase I study.
The company also continues to evaluate other preclinical candidates and expects to select one for formal development by the end of 2013. These include compounds targeting TKM-ALDH2, which targets aldehyde dehydrogenase 2, for alcohol dependence, and an siRNA cocktail designed against the cancer targets Wee1 and CSN5.
Tekmira and Murray did not, however, make any mention of the company's one-time flagship effort in hypercholesterolemia. That drug, called TKM-ApoB, is designed to silence apolipoprotein B and was the first the company moved into human trials.
However, it later halted a phase I study after a patient receiving the highest dose under investigation experienced flu-like symptoms consistent with stimulation of the immune system caused by the siRNA payload. It said that it planned to resume the program with a new siRNA and delivery formulation by mid-2010, but never did.
In late 2012, Murray said that the program remains in a holding pattern while Tekmira focuses on its two other clinical candidates.