Tetra Bio-Pharma Inc. announced that it has received a favorable Letter of Advice from the US Food and Drug Administration for QIXLEEF. FDA Feedback continues to support the development of QIXLEEF for second or third line therapy for adult patients with uncontrolled pain. FDA advice consistent with previous feedback paving the way for the marketing approval of QIXLEEF. On January 26, 2017, FDA had previously provided in-depth guidance to Tetra on the development of QIXLEEF (PPP001). This Letter of Advice provides Tetra new guidance based on clinical and safety progress with the quality of QIXLEEF and lays out the requirements for marketing approval (i.e. approved for sale) for cancer and non-cancer pain indications.