TKM-PLK1 Resulted in Clinical Benefit in 44% of Evaluable Patients Receiving Doses in Effective Range Tekmira to Initiate a Phase II Clinical Trial in Gastrointestinal Carcinoid (Neuroendocrine) Cancer Conference Call at 4:30 pm ET Today VANCOUVER, B.C., April 9, 2013 (GLOBE NEWSWIRE) -- Tekmira Pharmaceuticals Corporation (Nasdaq:TKMR) (TSX:TKM), a leading developer of RNA interference (RNAi) therapeutics, announced the results of its Phase I clinical trial with TKM-PLK1, an RNAi therapeutic for the treatment of solid tumors. The data are being presented today at 3:30 pm ET at the annual meeting of the American Association for Cancer Research (AACR) in an oral presentation entitled "A phase I dose escalation study of TKM-080301, a RNAi therapeutic directed against PLK1, in patients with advanced solid tumors." In this Phase I study, TKM-PLK1 was generally well-tolerated and showed encouraging signs of drug activity with RNAi activity confirmed in tumor biopsy. "We are very pleased with the results of our TKM-PLK1 Phase I clinical trial in a population of advanced cancer patients with solid tumors. The data generated from this clinical trial demonstrated that TKM-PLK1 was generally well-tolerated. In particular, we are very encouraged that four out of nine (44%) evaluable patients treated at doses in a range consistent with preclinical efficacy showed clinical benefit. In addition, we have confirmed RNAi activity in tumor biopsy. A variety of tumor types were treated in this Phase I study, but of particular note, of the two patients enrolled with gastrointestinal carcinoid (neuroendocrine) cancer, both responded to treatment with TKM-PLK1, and we look forward to initiating a Phase II clinical trial in this indication where there is a significant unmet medical need," said Dr. Mark J. Murray, Tekmira's President and CEO. TKM-PLK1, which employs a unique lipid nanoparticle (LNP) formulation for oncology applications, was administered to 24 patients at doses ranging from 0.15 mg/kg to 0.90 mg/kg; with a total of 152 doses administered and a mean number of 6.2 doses per patient (range of 1-31 doses). The most common grade 1-2 adverse events were rigors (33%) and fever (25%). No dose-dependent changes in liver function tests were observed. Dose-limiting toxicities included: one grade 3 transient thrombocytopenia in one patient (at 0.9 mg/kg) and one grade 3 hypoxia/dyspnea in another patient (at 0.9 mg/kg). Based on these data, the maximum tolerated dose is estimated to be 0.75 mg/kg. A 10-patient expansion cohort is currently enrolling patients at 0.75 mg/kg, with data expected later this year.