Heat Biologics is looking to buy an 80% stake in immuno-oncology firm Pelican Therapeutics, which is developing a preclinical pipeline of agonists targeting the T-cell co-stimulator TNFRSF25. Under terms of the proposed deal, Heat will pay Pelican shareholders up to $500,000 in cash, and issue shares in its own common stock amounting to a 4.99% stake in Heat's shareholding. The transaction is still subject to customary closing conditions and is dependent upon the holders of 80% of Pelican stock agreeing to sell.
Pelican’s lead TNFRSF25 agonist PTX-25 is a humanized monoclonal antibody designed to activate memory CD8+ cytotoxic T cells. PTX-15, the firm’s second candidate, is a human TL1A-Ig fusion protein designed to trigger regulatory T-cell proliferation. In May last year, Austin, TX-based Pelican won a $15.2 million New Company Product Development award from the Cancer Prevention and Research Institute of Texas (CPRIT) to support development of PTX-25 through a first-in-human clinical trial. At the time the firm said it anticipated making an IND filing in 2017.
Heat founder and CEO Jeff Wolf, said, “Pelican’s two product candidates are transformative assets for us as there are compelling data indicating that targeting TNFRSF25 may have significant advantages over competing co-stimulatory receptors currently under development. This is important because many of the leading global pharmaceutical companies are focused on T-cell co-stimulators to enhance the effectiveness of their existing immuno-oncology therapies.”
Heat suggests that PTX-25 combined with immunotherapies including its own ImPACT (Immune Pan-Antigen Cytotoxic Therapy) and ComPACT (Combination Pan-Antigen Cytotoxic Therapy) technologies could boost anticancer responses. “Pelican’s PTX-25 has the potential to dramatically improve the durability of antigen-specific immune responses due to its preferential specificity for stimulating the production of memory CD8+ T cells,” suggested Jeff Hutchins, Ph.D., Heat’s CSO and svp of preclinical development. “We look forward to advancing these new product candidates with synergistic combinations, including Heat’s existing T-cell-activating platform technologies, ImPACT, and ComPACT, vastly expanding our reach within oncology and possibly beyond.”
Heat Biologics is developing its off-the-shelf allogeneic ImPACT cell-based immunotherapies for use in the treatment of a wide range of cancers. The firm’s lead ImPACT products HS-410 (Vesigenurtacel-L) and HS-110 (Viagenpumatucel-L) are in Phase II development for the treatment of non-muscle invasive bladder cancer (NMIBC), and non-small-cell lung cancer (NSCLC), respectively.
In December 2016, Heat reported positive topline data from a Phase Ib study evaluating HS0110 in combination with Bristol-Myers Squibb’s anti-PD-1 checkpoint inhibitor nivolumab (Opdivo®) for the treatment of NSCLC.
The previous month Heat presented topline data from a 1-year Phase II study evaluating HS-410 both as monotherapy and in combination with standard of care Bacillus Calmette-Guérin (BCG) for the treatment of NMIBC. The firm said that while the results did indicate that HS-410 therapy led to antigen-specific immune repsonses to tumor-associated peptides, the responses didn’t translate into clinical outcome. There was no improvement in recurrence-free survival at 1 year (the study's primary endpoint). As a result, Heat is extending its monitoring time for trial patients to 2 years before making a decision on whether to progress the bladder cancer program into Phase III.
