CTI BioPharma Corp. announced that the full clinical hold (February 2016) implemented by the U.S. Food and Drug Administration on all clinical trials conducted under the Investigational New Drug (IND) application for pacritinib has now been removed. The company's complete response submission included, among other items, final Clinical Study Reports for both PERSIST-1 and 2 trials and a dose-exploration clinical trial protocol that the FDA requested. The new trial, PAC203 plans to enroll up to approximately 105 patients with primary myelofibrosis who have failed prior ruxolitinib therapy to evaluate the safety and the dose response relationship for efficacy (spleen volume reduction at 24 weeks) of three dose regimens: 100 mg once-daily, 100 mg twice-daily (BID) and 200 mg BID. The 200 mg BID dose regimen was used in PERSIST-2. The company expects to start the trial in the second quarter of 2017.