Leap Therapeutics Presents Positive Data From Clinical Study Of DKN-01 In Combination With Paclitaxel In Esophageal Cancer

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Leap Therapeutics, an immuno-oncology company, reported updated results from a clinical trial of its lead candidate DKN-01, a monoclonal antibody against the Dickkopf-1 (DKK1) protein. Data from the trial demonstrated clinical activity in patients with relapsed or refractory cancer of the esophagus or gastro-esophageal junction (GEJ), indications with few or no approved therapies.

“The results from the study of DKN-01 in combination with paclitaxel are promising. We look forward to the data from the next phases of this trial and further interrogating the activity of DKN-01 in additional trials going forward”

In Study Parts A and B, the dose escalation and dose confirmation phases, eight of 22 patients achieved a partial response (“PR”) per RECIST v1.1. Preliminary data indicated an overall progression-free survival (“PFS”) of 3.9 months, and 6.2 months and 3.2 months for patients with adenocarcinoma (AC) and squamous cell carcinoma (ESCC), respectively. DKN-01 was generally well tolerated. The data were presented today by Deva Mahalingam, M.D., of the University of Texas Health Science Center and an investigator on the trial, at the European Society for Medical Oncology’s World Congress on Gastrointestinal Cancer in Barcelona.

“Relapsed or refractory esophageal carcinomas are typically highly invasive and have a poor prognosis. The clinical activity we have seen to-date has been promising and is greater than expected compared to historical controls,” commented Dr. Mahalingam.

“The results from the study of DKN-01 in combination with paclitaxel are promising. We look forward to the data from the next phases of this trial and further interrogating the activity of DKN-01 in additional trials going forward,” commented David Ryan, M.D. of Massachusetts General Hospital and an investigator on the trial.

Results from Part A and Part B of the P102 Study of DKN-01 in Esophageal Carcinoma:

• Twenty-seven patients with cancer of the esophagus or GEJ were enrolled in Parts A and B; 22 were evaluable per the protocol at the date of this analysis
• The combination of DKN-01 and paclitaxel was safe and well tolerated at all doses with no treatment related severe adverse events (SAEs) related to either DKN-01 or paclitaxel
• The most frequently reported DKN-01-related AEs were fatigue, diarrhea, and decreased appetite
• Eight patients (36.4%) had PRs and nine (40.9%) patients had best responses of Stable Disease, with a total disease control rate of 77%
• Durable responses with patients remaining on therapy for 12+ months
• Two long-term patients (one AC, one ESCC) with PRs continue on DKN-01 monotherapy with continued deepening of response as a single agent
• Preliminary overall PFS for patients with adenocarcinoma of the esophagus or GEJ of 6.2 months and patients with squamous cell carcinoma of 3.2 months

About Esophageal Cancer

Esophageal cancer is an aggressive disease with 17,000 patients diagnosed annually in the US and 400,000 diagnosed worldwide. Over 50% of patients are diagnosed with advanced disease, with an expected overall survival limited to 8-12 months. There are no approved therapies for relapsed or refractory disease of the esophagus, with the majority of patients receiving single-agent paclitaxel as a 2^nd-line therapy. While studies of efficacy are limited, response rates have historically ranged between 5-15% and progression-free survival of 1-3 months.

About DKN-01

DKN-01 is a humanized IgG4 monoclonal antibody with neutralizing activity against the Dickkopf-1 (DKK1) protein. DKK1 expression in cancer tissue has been associated with poor prognosis in multiple cancers, and recent literature suggests DKK1 has a critical role in mediating an immuno-suppressive tumor microenvironment. DKN-01 is currently being studied in clinical trials in esophageal cancer and cholangiocarcinoma. DKN-01 additionally demonstrated single agent activity in NSCLC in a Phase 1 dose escalation study that was presented at ASCO 2014.

About Leap Therapeutics

Leap Therapeutics is an immuno-oncology company with two clinical stage programs. Leap’s most advanced clinical candidate, DKN-01, is a humanized monoclonal antibody targeting the Dickkopf-1 (DKK1) protein. DKN-01 is in Phase 1/2 clinical trials in esophageal cancer and cholangiocarcinoma. Leap’s second clinical candidate, TRX518, is a novel, humanized anti-GITR monoclonal antibody designed to enhance the immune system’s anti-tumor response. For more information of Leap Therapeutics, visit http://www.leaptx.com.

FORWARD LOOKING STATEMENTS:

Some of the statements in this release are forward looking statements within the meaning of Section 27A of the Securities Act of 1933, Section 21E of the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act of 1995, which involve risks and uncertainties. These statements relate to future events of Leap’s pre-clinical and clinical development of DKN-01, TRX518 and other programs, future expectations, plans and prospects. Although Leap believes that the expectations reflected in such forward-looking statements are reasonable as of the date made, expectations may prove to have been materially different from the results expressed or implied by such forward-looking statements. Leap has attempted to identify forward looking statements by terminology including ‘‘believes,’’ ‘‘estimates,’’ ‘‘anticipates,’’ ‘‘expects,’’ ‘‘plans,’’ ‘‘projects,’’ ‘‘intends,’’ ‘‘potential,’’ ‘‘may,’’ ‘‘could,’’ ‘‘might,’’ ‘‘will,’’ ‘‘should,’’ ‘‘approximately’’ or other words that convey uncertainty of future events or outcomes to identify these forward-looking statements. These statements are only predictions and involve known and unknown risks, uncertainties, and other factors. Any forward looking statements contained in this release speak only as of its date. We undertake no obligation to update any forward-looking statements contained in this release to reflect events or circumstances occurring after its date or to reflect the occurrence of unanticipated events.