Cell Therapeutics (CTI) is acquiring worldwide rights to S*BIO’s selective JAK2 inhibitor pacritinib (SB1518). CTI will make an up-front payment of $15 million and issue $15 million shares of unregistered preferred stock convertible into common stock in CTI. The agreement also includes regulatory success- and sales-based milestone payments as well as single-digit royalties on net sales.
"JAK2 dysregulation is associated with a broad range of difficult-to-treat illnesses, including cancers and autoimmune diseases, and is one of the most exciting potential new targets in cancer therapy today," says James A. Bianco, M.D., CEO of Cell Therapeutics.
The deal boosts CTI’s pipeline of drugs to treat blood-related disorders including blood cancer. It comes about a year after the company paid Chroma $5 million up front for its late-stage treatment for acute myeloid leukemia (AML), tosedostat. The compound is an oral aminopeptidase inhibitor designed to block protein recycling and lead to tumor cell death.
Pacritinib has demonstrated encouraging clinical benefit in Phase I and II in patients with primary myelofibrosis (MF) or MF secondary to other myeloproliferative neoplasms (MPN), according to CTI and S*BIO. The compound has orphan drug designation in the U.S. and Europe for myelofibrosis. CTI will be solely responsible for development and commercialization activities of pacritinib worldwide.
"We believe a highly selective JAK2 inhibitor that also inhibits the JAK2 clonal mutation (JAK2V617F) offers a distinct biological and clinical advantage over marketed or development-stage compounds, which are nonselective inhibitors of the JAK pathway,” Dr. Bianco adds. “We believe that the lack of suppression of red blood cell and platelet formation seen with pacritinib has the potential to satisfy a medical need not currently addressed with existing nonselective JAK1/JAK2 inhibitors."
S*BIO is a privately held biotechnology company focused on the research and clinical development of novel targeted small molecule drugs for the treatment of cancer with leading programs around kinases and histone deacetylases (HDAC). The company has a second JAK2 inhibitor in development, SB1578, which is in Phase I testing in RA and psoriasis.
Pacritinib is an oral, once a day, tyrosine kinase inhibitor (TKI) with dual activity against JAK2 and FMS-like tyrosine kinase 3 (FLT3). Mutations in these kinases have been shown to be directly related to the development of a variety of blood related cancers including MPD, leukemia, and lymphoma. FLT3 is a commonly mutated gene found in acute myeloid leukemia patients, and its activating mutations have been proven to be a negative prognostic marker for clinical outcome suggesting a possible future role for treatment of AML.
"The acquisition of pacritinib is aligned with our strategy of becoming a leader in the treatment of blood-related cancers and disorders," Bianco continues. "With Pixuvri approaching approval and launch in the EU and tosedostat and pacritinib entering Phase III, our late-stage portfolio addresses a full complement of blood-related cancers ranging from MPN to MDS, leukemia, and lymphoma."
CTI has had a long and winding road with the development of Pixuvri. On February 17, EMA’s Committee for Medicinal Products for Human Use (CHMP) granted the drug a positive opinion for conditional approval as a monotherapy for the treatment of adult patients with multiple relapsed or refractory aggressive non-Hodgkin B-cell lymphomas.
On January 30, however, the company withdrew its NDA covering the same indications, saying that it needed additional time to prepare for the review of Pixuvri by FDA’s Oncologic Drugs Advisory Committee. Since the agency couldn’t change CTI’s review and PDUFA schedule, the company decided to withdraw its application and refile it later this year.