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Bolder BioTechnology Announces Positive Results from Phase 1 Clinical Trial of BBT-015, a Long-Acting G-CSF Analog, in Healthy Volunteers

Boulder, Colorado – April 27, 2018- Bolder BioTechnology, Inc. announced today that it has completed a Phase 1 clinical trial of BBT-015, a proprietary long-acting granulocyte colony-stimulating factor (G-CSF) analog, in healthy human volunteers. BBT-015 is being developed as a treatment for chemotherapy-related neutropenia in cancer patients and for Acute Radiation Syndrome. Demonstration that the drug is safe in healthy volunteers is one of the requirements for Food and Drug Administration approval of the drug to treat Acute Radiation Syndrome.

Joe Cox, Ph.D., Bolder BioTechnology’s President said, “We are very pleased with the results of this trial, which appear to confirm the increased potency of BBT-015 compared to other approved G-CSF products.  The trial studied the pharmacokinetics, pharmacodynamics, safety and tolerability of single subcutaneous administrations of three different dose levels of BBT-015 (0.01, 0.04, and 0.1 mg/kg), and a single dose level (0.1 mg/kg) of a comparator drug, pegfilgrastim (Neulastaâ, Amgen, Inc.).  There were 5 male subjects per treatment group.  The clinical trial was conducted by Celerion, Inc. (Lincoln, NE), and we are grateful for their rapid patient recruitment and excellent study performance.”

“BBT-015 plasma levels were dose-dependent, being highest in subjects receiving the 0.1 mg/kg dose; at this dose, mean peak BBT-015 plasma levels were about two-fold higher than mean peak pegfilgrastim plasma levels.  All BBT-015 doses stimulated long-lasting increases in circulating neutrophils.  Mean peak neutrophil levels reached a maximum in subjects treated with 0.04 mg/kg and 0.1 mg/kg BBT-015, and were higher in these subjects than in subjects treated with 0.1 mg/kg pegfilgrastim.”

“BBT-015 also stimulated dose-dependent increases in circulating peripheral blood progenitor cells (CD34+ cells), which are used in hematopoietic stem cell transplants.  Mean peak CD34+ cell numbers were about 50% higher in subjects treated with 0.1 mg/kg BBT-015 compared to subjects treated with the 0.1 mg/kg pegfilgrastim.”

“All BBT-015 doses were well tolerated and all subjects completed the trial.  All adverse events attributed to BBT-015 were rated as mild, while adverse events attributed to pegfilgrastim were rated as mostly mild, with a couple moderate. Musculoskeletal pain and headaches were the most frequent adverse events for both drugs.  Subjects treated with the 0.01 and 0.04 mg/kg BBT-015 experienced fewer than half as many adverse events as subjects treated with 0.1 mg/kg BBT-015 or 0.1 mg/kg pegfilgrastim.  None of the 15 subjects treated with BBT-015 reported feeling nauseous or vomiting, which are common side effects of other G-CSF drugs.  None of the subjects developed antibodies to BBT-015 or pegfilgrastim.“

“Although subject numbers in this trial are small, the data are very promising and warrant further study of BBT-015 in additional clinical trials.”

About BBT-015

BBT-015 is a long-acting G-CSF analog that stimulates production of neutrophils, a type of white blood cell important for fighting infections.  G-CSF has a short half-life in humans and typically is administered to patients by daily injection.  BBT-015 has been selectively modified with the polymer polyethylene glycol at a unique site in the protein, which allows the protein to last longer in patients, reducing the need for frequent administration and increasing the protein’s ability to stimulate long-lasting production of neutrophils.

About Bolder BioTechnology

Bolder BioTechnology, Inc. is a private company that uses advanced protein engineering and bioconjugation technologies to create proprietary human protein pharmaceuticals with enhanced therapeutic properties. For additional information about Bolder BioTechnology, Inc., please visit our web site at www.bolderbio.com.

Forward Looking Statements

Statements contained herein that are not historical facts are forward-looking statements that are subject to a variety of risks and uncertainties.  Important factors that could cause actual results to differ materially from those expressed in any forward-looking statements made by the Company include, but are not limited to: (1) the Company’s ability to successfully complete product research and development, including pre-clinical and clinical studies, and commercialization; (2) the Company’s ability to obtain required government approvals; (3) the Company’s ability to attract and/or maintain manufacturing, sales, distribution and marketing partners; and (4) the Company’s ability to develop and commercialize its products before its competitors.

Media Contact:  Joe Cox, Ph.D., President

Phone: (303) 420-4420 x-202

Email: jcox@bolderbio.com