CX1739: Preliminary Phase IIa data

In September, RespireRx reported preliminary data from 15 patients who achieved >25% depression of their respiratory rate following an acute IV bolus injection of 1ug/kg remifentanil in the double-blind Stage 1 of a 2-stage, crossover, U.S. Phase IIa trial showing that pretreatment with a single dose of 300 mg oral CX1739 significantly reduced mean recovery time from the maximal respiratory depressant effects of remifentanil vs. placebo (4.4 vs. 6.8 minutes, p=0.01). In Stage 1 of the trial, 21 patients received placebo or 300 mg oral CX1739 followed about 3 hours later by an acute IV bolus injection of remifentanil. Thirty minutes after the bolus injection of remifentanil, patients received a 0.25 ug/kg bolus of remifentanil followed by a continuous IV infusion calculated to achieve blood levels of 2 ng/mL. The open-label Stage 2 evaluated single doses of 600 and 900 mg oral CX1739 in the same manner as Stage 1. The 600 and 900 mg doses of CX1739 did not reduce mean recovery time from the maximal respiratory depressant effects of an acute IV bolus injection of 1ug/kg remifentanil vs. placebo or the 300 mg dose of CX1739. However, mid- and high-dose CX1739 did significantly reduce respiratory depression following a continuous IV infusion of remifentanil vs. placebo (p<0.05 and p=0.01, respectively). CX1739 was well tolerated with no serious adverse events reported. The most common adverse events reported were nausea, vomiting, headache and dizziness. The trial was conducted in collaboration with Duke University School of Medicine...