CTI BioPharma Corp. announced that the full clinical hold (February 2016) implemented by the U.S. Food and Drug Administration (FDA) on all clinical trials conducted under the Investigational New Drug (IND) application for pacritinib has now been removed. The Company’s 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 effectiveness of pacritinib. The Company expects to start the trial in the second quarter of 2017.
A company spokesman communicated “We are pleased to resolve the full clinical hold through working diligently with the FDA to provide a comprehensive response to their requests,” said Richard Love, Interim President and CEO of CTI BioPharma. “We look forward to discussing with the FDA the future development of pacritinib. We believe pacritinib can ultimately address the unmet need of patients with myelofibrosis who are ineligible to receive or are not benefitting from the approved JAK1/JAK2 inhibitor, ruxolitinib, as these patients have limited treatment options.”
Myelofibrosis is a type of blood cancer known as a myeloproliferative neoplasm. It involves the abnormal development and function of bone marrow cells that produce blood cells which leads to the formation of scar tissue in the bone marrow. This can cause anemia, enlargement of the spleen and liver, fatigue, and other problems. In some patients with myelofibrosis, the condition progresses to acute myeloid leukemia.
Proteins known as JAK1 and JAK2 may play a role in the development of MPNs, including myelofibrosis, by causing the body to make the wrong number of blood cells. Drugs that suppress JAK1 and JAK2 are used to treat different forms of MPN by reducing the number of abnormal blood cells associated with these disorders. JAK1/JAK2 inhibitors can, however, result in too much suppression of the bone marrow’s production of blood cells. Known as myelosuppression, this condition can negatively impact patient health and quality of life.
Pacritinib is designed to fight myelofibrosis by interfering with the kinases JAK2 and FLT3 to potentially keep tumors from developing. Unlike other JAK inhibitors, pacritinib does not cause myelosuppression, which, if safe and effective, could offer an advantage to patients.