ProNAi Therapeutics Granted Orphan Drug Designation for PNT2258 for the Treatment of Diffuse Large B-Cell Lymphoma

VANCOUVER, March 14, 2016 /PRNewswire/ - ProNAi Therapeutics, Inc. (NASDAQ: DNAI), a clinical-stage oncology company advancing novel therapeutics for patients with cancer and hematological diseases, today announced that its oncology drug candidate PNT2258 has been granted Orphan Drug Designation by the U.S. Food and Drug Administration (FDA) for the treatment of diffuse large B-cell lymphoma (DLBCL). This is the second orphan drug designation obtained by ProNAi for PNT2258 for the treatment of DLBCL, following a similar grant by the European Commission in August 2015.

"Achieving this regulatory milestone for PNT2258 is an important advancement in our registration-oriented development plan for this cancer drug in DLBCL, a disease for which there are limited treatment options, particularly in patients who relapse or do not respond to front-line therapies." said Dr. Nick Glover, President and CEO of ProNAi.

Orphan drug designation is typically granted for novel drugs or biologics that are intended to treat rare medical diseases or conditions that affect less than 200,000 people in the United States. The designation qualifies the sponsor for certain incentives including seven years of market exclusivity after a drug's approval, tax credits for clinical research costs, and certain application fee waivers.

ProNAi has also previously received European Commission Orphan Drug Designation for PNT2258 for the treatment of patients with DLBCL. In addition to a 10-year period of market exclusivity in the EU following marketing authorization, receiving orphan drug designation provides other incentives for companies, including scientific advice and protocol assistance during the product's development phase.

About PNT2258 and DLBCL
ProNAi is actively enrolling patients in "Wolverine", a Phase 2 trial evaluating PNT2258 for the treatment of relapsed or refractory DLBCL and in "Brighton", a Phase 2 trial evaluating PNT2258 for the treatment of Richter's transformation.

PNT2258 is designed to target cancers that overexpress BCL2, an important and validated oncogene known to be dysregulated in many types of cancer. BCL2 overexpression is thought to be a key driver of DLBCL, an aggressive form of cancer that is the most prevalent form of Non-Hodgkin lymphoma (NHL), comprising approximately 30% of the annual NHL diagnoses in the United States according to the Leukemia & Lymphoma Society (2013).

DLBCL affects mostly middle aged and older adults and is aggressive but potentially curable. First-line treatment of intensive combination chemotherapy involving rituximab may cure approximately 67% of patients. If this fails, second-line treatment is typically platinum-based chemotherapy along with continued rituximab. In the event that a response is achieved with second-line treatment, patients may be given a hematopoietic stem cell transplant. If second-line treatment or the transplant fails, patients are left with few options and little hope of a curative therapy. The median survival for third-line DLBCL patients is less than a year.

About ProNAi Therapeutics
ProNAi Therapeutics is a clinical-stage oncology company advancing novel therapeutics for patients with cancer and hematological diseases. For more information, please visit www.pronai.com.

Cautionary Note on Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, including, but not limited to, statements regarding ProNAi's anticipated clinical development, marketing exclusivity and potential business development strategies. All statements other than statements of historical fact are statements that could be deemed forward-looking statements. These statements are based on management's current expectations and beliefs and are subject to a number of risks, uncertainties and assumptions that could cause actual results to differ materially from those described in the forward-looking statements. Such forward-looking statements are subject to risks and uncertainties, including, among others, the risk that ProNAi may be unable to successfully develop and commercialize PNT2258 or any other future product candidates, PNT2258 may fail to demonstrate safety and efficacy or may not otherwise produce positive results, ProNAi may experience delays in clinical trials, including due to difficulties enrolling patients, ProNAi's third-party manufacturers may cause its supply of materials to become limited or interrupted or fail to be of satisfactory quantity or quality, ProNAi's cash resources may be insufficient to fund its current operating plans and it may be unable to raise additional capital when needed, ProNAi may be unable to obtain and enforce intellectual property protection for its technologies and product candidates and the other factors described under the heading "Risk Factors" set forth in ProNAi's filings with the Securities and Exchange Commission from time to time, including the Company's reports filed with the Securities and Exchange Commission. ProNAi undertakes no obligation to update the forward-looking statements contained herein or to reflect events or circumstances occurring after the date hereof, other than as may be required by applicable law.

SOURCE ProNAi Therapeutics Inc.