Merrimack Pharmaceuticals Receives FDA Fast Track Designation for MM-398 in Post-Gemcitabine Metastatic Pancreatic Cancer

CAMBRIDGE, Mass., Nov. 19, 2014 (GLOBE NEWSWIRE) -- Merrimack Pharmaceuticals, Inc. (Nasdaq:MACK) announced today that the U.S. Food and Drug Administration (FDA) has granted MM-398 (nanoliposomal irinotecan injection), also known as ''nal-IRI,'' Fast Track designation for the treatment of patients with metastatic adenocarcinoma of the pancreas who have been previously treated with gemcitabine-based therapy. Fast Track is designed by the FDA to facilitate and expedite the development and review of drugs that treat serious conditions and fill an unmet medical need.

Pancreatic cancer is the fourth leading cause of cancer-related deaths in the United States and is projected to be the second highest cause of death from cancer in the United States by 2020. It is a rare and deadly disease that is difficult to diagnose and has limited treatment options available.

"It is crucial to develop new therapies for patients with pancreatic cancer, particularly for those patients who have previously received gemcitabine-based therapy where there is currently no consensus on the standard of care," said Eliel Bayever, M.D., Vice President at Merrimack and medical director for MM-398. "We will continue to work diligently on our NDA submission in an effort to bring MM-398 to patients who are facing this aggressive disease as quickly as possible."

Merrimack is currently preparing a New Drug Application (NDA) for MM-398 in the United States for the treatment of patients with metastatic pancreatic cancer previously treated with a gemcitabine-based therapy. Fast Track designation allows sections of the NDA to be submitted to the FDA as they are completed. Based upon this designation, Merrimack expects to initiate the NDA submission in 2014 with the goal of completing the NDA submission late in the first quarter or early in the second quarter of 2015.

The US FDA and European Medicines Agency have granted MM-398 orphan drug designation in metastatic pancreatic cancer. Merrimack and Baxter International's biopharmaceutical business (NYSE:BAX) entered into an exclusive licensing agreement to develop and commercialize MM-398 outside of the United States. Baxter expects to submit for regulatory approvals outside of the United States beginning in 2015.

About MM-398

MM-398 (irinotecan liposome injection), also known as "nal-IRI," is a nanoliposomal encapsulation of the chemotherapeutic irinotecan. MM-398 has demonstrated extended circulation in comparison to free irinotecan in the clinical setting. The activated form of irinotecan is SN-38, which functions by inhibiting topoisomerase I (an essential enzyme involved in DNA transcription and replication) and promoting cell death. In 2014, Merrimack and Baxter International's biopharmaceutical business (NYSE:BAX) entered into an exclusive licensing agreement to develop and commercialize MM-398 outside of the United States and Taiwan. PharmaEngine, Inc. (Taipei, Taiwan) holds the rights to commercialize MM-398 in Taiwan.

About Pancreatic Cancer 1,2

Pancreatic cancer is rare and deadly, accounting for only three percent of all cancer cases worldwide but is the fourth leading cause of cancer death. An estimated 140,000 new cases are diagnosed every year around the world, two-thirds of which are among people aged 65 or older. In the United States alone, approximately 46,000 people are diagnosed with pancreatic cancer and about 40,000 patients die annually.

Because the signs and symptoms of pancreatic cancer are non-specific and may not appear until the disease has spread to other sites, approximately 80% of patients are diagnosed with late stage disease and are not candidates for surgery, instead receiving chemotherapy as the mainstay of their therapy. As a result, the five year survival rate is less than six percent; fewer than 20 percent of newly diagnosed patients survive more than two years. There is no consensus on the standard of care for patients with metastatic pancreatic cancer previously treated with a gemcitabine-based therapy.

About Merrimack

Merrimack is a biopharmaceutical company discovering, developing and preparing to commercialize innovative medicines paired with companion diagnostics for the treatment of cancer. Merrimack seeks to gain a deeper understanding of underlying cancer biology through its systems biology-based approach and develop new insights, therapeutics and diagnostics to improve outcomes for cancer patients. Merrimack currently has six oncology therapeutics in clinical development and three additional candidates in late stage preclinical development. Merrimack's lead product candidate, MM-398, recently completed a Phase 3 trial in post-gemcitabine pancreatic cancer. Based on the results of this trial, Merrimack is currently preparing a New Drug Application for MM-398. For more information, please visit Merrimack's website at or connect on Twitter at @MerrimackPharma.

Forward-Looking Statements

To the extent that statements contained in this press release are not descriptions of historical facts, they are forward-looking statements reflecting the current beliefs and expectations of management made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, as amended. Forward-looking statements include any statements about Merrimack's strategy, future operations, future financial position and future expectations and plans and prospects for Merrimack, and any other statements containing the words "anticipate," "believe," "estimate," "expect," "intend," "may," "plan," "predict," "project," "target," "potential," "will," "would," "could," "should," "continue," "hope" and similar expressions. In this press release, Merrimack's forward-looking statements include statements about the timing of submitting a New Drug Application to the FDA. Such forward-looking statements involve substantial risks and uncertainties that could cause Merrimack's clinical development programs, future results, performance or achievements to differ significantly from those expressed or implied by the forward-looking statements. Such risks and uncertainties include, among others, availability of data from ongoing clinical trials, expectations for regulatory approvals, development progress of Merrimack's companion diagnostics and other matters that could affect the availability or commercial potential of Merrimack's drug candidates or companion diagnostics. Merrimack undertakes no obligation to update or revise any forward-looking statements. Forward-looking statements should not be relied upon as representing Merrimack's views as of any date subsequent to the date hereof. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to Merrimack's business in general, see the "Risk Factors" section of Merrimack's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (SEC) on November 10, 2014 and other reports Merrimack files with the SEC.

1 American Cancer Society. Cancer Facts and Figures 2014. Atlanta: American Cancer Society; 2014.

2 World Health Organization. GLOBOCAN 2012: Estimated Cancer Incidence, Mortality and Prevalence Worldwide in 2012; Lyon, Fr.: International Agency for Research on Cancer; 2012.

CONTACT: Media Contacts: Dana Robie Merrimack 617-441-7408 Liz Bryan Spectrum 202-955-6222 Investor Contact: Geoffrey Grande, CFA Merrimack 617-441-7602

Source:Merrimack Pharmaceuticals