GT Biopharma Inc. announced that it has completed dosing in its Phase 1 clinical trial for GTP-004, its promising treatment for the symptoms of myasthenia gravis. The results provide evidence that GTP-004 enables the safe and well-tolerated administration of doses of pyridostigmine. GTP-004 combines pyridostigmine with ondansetron, designed to attenuate the gastro-intestinal (GI) side effects of pyridostigmine alone, providing the potential for a fully efficacious dose of pyridostigmine to be safely used. Based on the data, and discussions with key opinion leaders, GT Biopharma expects to be in a position to initiate a Phase 2 clinical trial in patients in the second half of 2018. The objective of the Phase 1 clinical trial is to demonstrate that GI side effects are safely reduced with GTP-004. Five healthy volunteers were enrolled in the Phase 1 study. Following enrollment, subjects received single increasing oral doses of pyridostigmine (ranging from 30 to 120mg) administered once daily in the morning. Once subjects reached First Intolerable Dose (FID1) as defined by protocol criteria, upward dose escalation of pyridostigmine was discontinued and subjects were washed out for 2 to 7 days. Next, subjects that reached FID received daily increasing doses of pyridostigmine in combination with ondansetron. Three subjects (2 males, one female; aged 34 to 43) reached FID with pyridostigmine alone. The dose-limiting gastro-intestinal adverse event occurred at 60 mg for 2 subjects, and 90 mg for the third subject. When these three subjects received GTP-0004 (pyridostigmine with ondansetron), gastro-intestinal adverse events were abrogated, and all subjects tolerated doses as high as 120 mg, the maximum allowed dose allowed by the protocol.