Merrimack Pharmaceuticals Inc (NASDAQ:MACK) announced that an updated overall survival analysis of the Phase 3 NAPOLI-1 study of ONIVYDE® (irinotecan liposome injection) in combination with fluorouracil (5-FU) and leucovorin achieved a substantial improvement in 12-month overall survival in patients with post-gemcitabine metastatic pancreatic adenocarcinoma when compared to 5-FU and leucovorin alone. These updated data will be presented at the American Society of Clinical Oncology 2016 Gastrointestinal Cancers Symposium (ASCO GI), January 21-23, 2016, in San Francisco.

Analysis of the updated data supports the robustness of the overall survival benefit of the ONIVYDE combination therapy observed in the primary analysis of the NAPOLI-1 trial. Updated findings showed one in four patients treated with ONIVYDE survived a milestone of one year or more: 12-month overall survival estimates of 26% (95% CI, 18-35%) for ONIVYDE in combination with 5-FU and leucovorin, a 63% improvement when compared to 16% (95% CI, 10-24%) for 5-FU and leucovorin alone. No new safety or tolerability concerns were note in the updated analysis.

“Pancreatic cancer is a devastating disease with dismal survival,” said Andrea Wang-Gillam, M.D., Ph.D., lead author of the NAPOLI-1 article and Associate Professor of Medicine, Clinical Director of GI Oncology Program, Division of Oncology, at Washington University School of Medicine, St. Louis. “These updated findings reinforce the overall survival benefit of ONIVYDE in treating patients with metastatic pancreatic adenocarcinoma who have progressed after gemcitabine-based therapy. With a significant improvement in the 12-month overall survival rate and a well-defined safety and tolerability profile, the ONIVYDE combination regimen is well-positioned to become the standard of care in the post-gemcitabine setting. This new therapy offers hope for extended life expectancy in a patient population with limited options.”

Methodology and Results:

Updated overall survival analysis of NAPOLI-1: Phase 3 study of nanoliposomal irinotecan (nal-IRI, MM-398), with or without 5-fluorouracil and leucovorin (5-FU/LV), versus 5-FU/LV in metastatic pancreatic cancer (mPAC) previously treated with gemcitabine-based therapy (Abstract #417, Board L11)

In this analysis of updated data from the NAPOLI-1 study, the previously described overall survival and progression free survival benefits were maintained for the ONIVYDE in combination with 5-FU and leucovorin arm compared with 5-FU and leucovorin alone. This data analysis presents updated estimates of overall survival based on 378 events and includes data from all patients randomized across the three arms of the study. Twelve-month survival estimates for ONIVYDE in combination with 5-FU and leucovorin were 26% (95% CI, 18-35%) compared to 16% (95% CI, 10-24%) for 5-FU and leucovorin alone. Six-month survival estimates were 53% (95% CI, 44-62%) for the ONIVYDE combination regimen versus 38% (95% CI, 29-47%) for 5-FU and leucovorin. No new safety or tolerability concerns were noted in the updated data analysis. The most common grade 3+ adverse events occurring at a ≥ 2% incidence in the ONIVYDE-containing arms were neutropenia, diarrhea, vomiting, and fatigue.

Effect of baseline carbohydrate antigen 19-9 (CA19-9) level on overall survival (OS) in NAPOLI-1 trial: A Phase 3 study of MM-398 (nal-IRI), with or without 5-fluorouracil and leucovorin (5-FU/LV), versus 5-FU/LV in metastatic pancreatic cancer (mPAC) previously treated with gemcitabine-based therapy (Abstract #425, Board L19)

Carbohydrate antigen 19-9 (CA19-9) has been shown to correlate with response to therapy and overall survival in patients with metastatic pancreatic cancer. In this updated analysis ofNAPOLI-1 data, patients with a recorded baseline CA19-9 measurement were divided into quartiles to evaluate the treatment effect pattern of CA19-9 levels with ONIVYDE in combination with 5-FU and leucovorin or 5-FU and leucovorin alone. A total of 213 patients treated with the ONIVYDE combination regimen or 5-FU and leucovorin alone had a baseline CA19-9 measurement and were included in this analysis. Results show the observed overall survival and progression free survival benefits for the ONIVYDE combination regimen compared to 5-FU and leucovorin alone were greatest among patients with the highest baseline CA19-9 levels. These results suggest that baseline CA19-9 levels are associated with the treatment effect observed for the ONIVYDE combination regimen in metastatic pancreatic cancer patients. (Original Source)

Shares of Merrimack Pharmaceuticals Inc. closed yesterday at $5.97 . MACK has a 1-year high of $13.84 and a 1-year low of $5.79. The stock’s 50-day moving average is $7.68 and its 200-day moving average is $9.38.

On the ratings front, Merrimack Pharmaceuticals has been the subject of a number of recent research reports. In a report issued on December 24, Oppenheimer analyst Ling Wang assigned a Buy rating on MACK, with a price target of $15, which represents a potential upside of 151.3% from where the stock is currently trading. Separately, on December 23, Mizuho’s Eric Criscuolo maintained a Buy rating on the stock and has a price target of $13.

According to TipRanks.com, which ranks over 7,500 financial analysts and bloggers to gauge the performance of their past recommendations, Ling Wang and Eric Criscuolo have a total average return of -21.5% and -16.6% respectively. Wang has a success rate of 15.0% and is ranked #3562 out of 3582 analysts, while Criscuolo has a success rate of 20.0% and is ranked #3130.

Merrimack Pharmaceuticals Inc is engaged in discovering, developing and preparing to commercialize medicines consisting of novel therapeutics paired with companion diagnostics for the treatment of cancer.