Benzinga | Apr 14, 2021 05:20AM EDT

Galectin Therapeutics Shares Up 36% Premarket; Co Announced Late Tuesday Journal for ImmunoTherapy of Cancer Publishes Phase 1 Clinical Research Shows Galectin-3 Inhibitor Belapectin Enhances Tumor Response in Combination with Anti-PD-1 Therapy

Galectin Therapeutics Inc. (NASDAQ:GALT) announced that a paper published in the peer-reviewed Journal for ImmunoTherapy of Cancer (JITC), the highest ranked fully open access immunology journal, provides further clinical evidence that using belapectin, a potent galectin-3 inhibitor, in combination with pembrolizumab (KEYTRUDA(r)), a PD-1 inhibitor, significantly enhances tumor response to immunotherapy in patients with advanced metastatic melanoma (MM) and head and neck squamous cell carcinoma (HNSCC).

The paper, titled "Enhancing Clinical and Immunological Effects of anti-PD-1 with Belapectin, a Galectin-3 Inhibitor" (doi:10.1136/jitc-2021-002371) describes results from an ongoing Phase 1 clinical study, a collaboration between Galectin Therapeutics and Providence Cancer Institute in Portland, Oregon.

Following the recent publication of positive preclinical results that showed the inhibition of galectin-3 in combination with an agonist anti-OX40 monoclonal antibody reprograms the tumor microenvironment to favor anti-tumor activity, the current study tests the clinical hypothesis that galectin-3 blockade with belapectin in combination with pembrolizumab enhances tumor response for patients with advanced MM or HNSCC.

In the study, as previously disclosed, an objective response was observed in 50% of MM (7/14) and 33% of HNSCC (2/6) patients. This compares favorably to published response rates on pembrolizumab alone. The authors noted that the combination was associated with fewer immune-mediated adverse events than anticipated with pembrolizumab alone. In addition, the analysis of patients' tumor tissue revealed reduced monocytic myeloid-derived suppressor cells and increased effector memory T-cell activation in responders compared with non-responders. Also, an increased baseline expression of galectin-3 positive tumor cells correlated with clinical response.

"Immunotherapy is a significant breakthrough in the treatment of many cancers, but tumor-induced immune suppression contributes to treatment resistance. Galectin-3 is an important driver of this tumor-induced immunosuppression, and this clinical study constitutes proof-of-concept that the addition of belapectin, a galectin-3 inhibitor, to a PD-1 inhibitor can benefit cancer patients," said Dr. Brendan Curti, M.D., Earle A. Chiles Research Institute, a division of Providence, and the first author of the paper.

"The analysis of patients' tumor tissues is consistent with previously published pre-clinical data with belapectin and confirms the ability of belapectin to modulate the tumor microenvironment to favor anti-tumor activity. The possibility to improve the tolerance and safety of immunotherapy is also very exciting," commented Pol F. Boudes, M.D., Chief Medical Officer of Galectin Therapeutics. "These proof-of-concept clinical data provide a strong rationale to initiate a randomized placebo-controlled phase 2 clinical trial to evaluate the efficacy and safety of belapectin in combination with a PD-1 inhibitor compared to a PD-1 inhibitor alone in this cancer patient population. We look forward to continuing our work with Providence Cancer Institute, and we anticipate the upcoming release of additional data from the expansion cohort in this study."