Galena Biopharma Presents Final GALE-401 Phase 2 Clinical Data at the 57th American Society of Hematology (ASH) Annual Meeting and Exposition

SAN RAMON, Calif., Dec. 8, 2015 (GLOBE NEWSWIRE) -- Galena Biopharma, Inc. GALE, a biopharmaceutical company committed to the development and commercialization of targeted oncology therapeutics that address major unmet medical needs, today announced the final data from the Company's GALE-401 (anagrelide controlled release (CR)) Phase 2 proof-of-concept clinical trial was presented at the 57th American Society of Hematology (ASH) Annual Meeting.

Poster #4074, "Final results of anagrelide controlled-release (GALE-401) safety, efficacy and pharmacokinetics in subjects with myeloproliferative neoplasms (MPN)-related thrombocytosis," presented data on the GALE-401-201, Phase 2, pilot, single arm, open label, multi-center study with eighteen patients enrolled. The study evaluated the safety and efficacy of anagrelide CR in subjects with thrombocytosis secondary to essential thrombocythemia (ET) and other MPNs.

The study demonstrated GALE-401 is well tolerated and the efficacy compares favorably to historical anagrelide immediate release (IR) with reported platelet count best response rates, based on the WHO 2008 criteria, of eleven (61.1%) complete responses (CR), four (22.2%) partial responses (PR), and an overall response rate (ORR) of 83.3%. Platelet response is defined as CR (≤ 400 x 10⁹/L), or PR (≤ 600 x 10⁹/L or ≥ 50% reduction from baseline) maintained for at least 4 weeks. The mean time to response, defined as platelet count ≤ 600 x10⁹/L, ranged from 1 to 9 weeks with GALE-401, which compares favorable to historical anagrelide IR, where time to response ranged from 4 to 12 weeks. Fourteen of 18 subjects enrolled experienced a treatment related adverse event (AE); however, the vast majority of AEs were Grade 1/2 with no patients discontinuing therapy due to progression of disease. Nine patients remain on trial and the median time of response has not yet been reached.

"The data presented demonstrate that GALE-401 remains a viable potential treatment option for patients suffering from MPN disorders, in particular, essential thrombocythemia," said Bijan Nejadnik, M.D., Executive Vice President and Chief Medical Officer. "The Phase 2 study enrolled patients with essential thrombocythemia and polycythemia vera including those who had previously been treated with anagrelide. Based on the data, we believe a randomized trial comparing GALE-401 vs. anagrelide IR in anagrelide naïve subjects is warranted. Galena intends to request a meeting with the FDA to determine the best development path to registration based on the results of the study."

The primary objective for the trial was to estimate the overall platelet response rate (ORR) with secondary objectives of safety, tolerability and pharmacokinetics (PK). Eligible patients met the following criteria: male or female ≥ 18 years of age; diagnosed with a MPN related elevated platelet count to include ET, chronic myelogenous leukemia, polycythemia vera, or primary myelofibrosis; platelet count ≥ 600 10⁹/L on two occasions at least 14 days apart prior to first dose of study drug; for patients with MPN diagnosis other than ET, concurrent anti-MPN treatment was permitted, provided that the doses were stable at least four weeks prior to first dose of study drug; and, patients were not receiving therapy specifically intended to reduce platelet counts. GALE-401 was administered at a starting dose of 0.5 mg twice daily (1.0 mg/day) and the dose was titrated at weekly intervals, on an individual basis, to determine the lowest dose required to achieve and maintain a target platelet count of 150–400 x 10⁹/L. Toxicities were based on NCI CTCAE v4.03.

Source: Verstovsek S et al. 2015 ASH Poster Presentation

About GALE-401 (Anagrelide Controlled Release)

GALE-401 (Anagrelide Controlled Release) contains the active ingredient anagrelide. The currently available immediate release formulation (Agrylin® or anagrelide IR) is approved by the FDA for the treatment of patients with thrombocythemia, secondary to myeloproliferative disorders, to reduce the elevated platelet count and the risk of thrombosis and to ameliorate associated symptoms including thrombo-hemorrhagic events. Adverse events associated with anagrelide IR, such as nausea, diarrhea, abdominal pain, palpitations, tachycardia, and headache, may be dose and plasma concentration dependent.  Reducing the maximum plasma concentration (C_max) is expected to reduce side effects, while preserving efficacy. GALE-401 is a reformulated, controlled release version of anagrelide. Final data on the Phase 2 pilot study with GALE-401 was presented in December 2015, ClinicalTrials.gov Identifier: NCT02125318.

About Myeloproliferative Neoplasms

Myeloproliferative neoplasms (MPNs) are a closely related group of hematological malignancies in which the bone marrow cells that produce the body's blood cells develop and function abnormally. The main MPNs are polycythemia vera (PV), chronic myelogenous leukemia (CML), primary myelofibrosis (PMF), and essential thrombocythemia (ET), all of which are associated with high platelet counts. The MPNs are progressive blood cancers that can strike anyone at any age, and for which there is no known cure.  

About Galena Biopharma

Galena Biopharma, Inc. is a biopharmaceutical company committed to the development and commercialization of targeted oncology therapeutics that address major unmet medical needs. Galena's development portfolio is focused primarily on addressing the rapidly growing patient populations of cancer survivors by harnessing the power of the immune system to prevent cancer recurrence. The Company's pipeline consists of multiple mid- to late-stage clinical assets, including novel cancer immunotherapy programs led by NeuVax™ (nelipepimut-S) and GALE-301. NeuVax is currently in a pivotal, Phase 3 clinical trial with several concurrent Phase 2 trials ongoing both as a single agent and in combination with other therapies. GALE-301 is in a Phase 2a clinical trial in ovarian and endometrial cancers and in a Phase 1b given sequentially with GALE-302.   For more information, visit www.galenabiopharma.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements include, but are not limited to, statements about the progress of the commercialization of our commercial products and development of Galena's product candidates, including GALE-401, patient enrollment in our clinical trials, as well as other statements related to the progress and timing of our development activities, present or future licensing, collaborative or financing arrangements or that otherwise relate to future periods. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including those identified under "Risk Factors" in Galena's Annual Report on Form 10-K for the year ended December 31, 2014 and most recent Quarterly Reports on Form 10-Q filed with the SEC. Actual results may differ materially from those contemplated by these forward-looking statements. Galena does not undertake to update any of these forward-looking statements to reflect a change in its views or events or circumstances that occur after the date of this press release.

NeuVax is a trademark of Galena Biopharma, Inc.