DURHAM — The U.S. Food & Drug Administration (FDA) has cleared Heat Biologics’ (NASDAQ:HTBX) Investigational New Drug (IND) application for a Phase 1 clinical trial to evaluate combining two of its immune-stimulating cell lines in patients with solid tumors resistant to standard treatment.

The trial, expected to begin enrolling patients in the fourth quarter 2019, will test combining Heat’s engineered HS-130 and HS-110 cell lines.

HS-130, an off-the-shelf genetically modified cell line, is engineered to express OX40, a key co-stimulator of immune system T cells.

“HS-130 represents a major advance in the broad utility and versatility of our T-Cell Activation Platform (TCAP),” said Jeff Wolf, founder and CEO of Heat in the announcement. “We are leveraging the scientific, clinical and manufacturing expertise that we refined in the development of our HS-110 program in our effort to advance multiple cell-based cancer therapeutics for the activation of patients’ immune systems.”

“HS-130 is the first cell-based approach that utilizes OX40 co-stimulation,” explained Jeff Hutchins, Ph.D., Heat’s chief scientific and operating Officer. “In our first-in-human dose escalation study, we are evaluating the potential synergy of combining HS-130 with HS-110.”

Heat Biologics moving HQ to Morrisville from Durham

HS-110 is a cell line derived from lung cancer cells that creates a two-pronged immune response, stimulating both cancer-fighting antigens and gp96, the body’s most powerful natural immune system aid.

HS-110 is currently being evaluated in a Phase 2 clinical trial for advanced non-small cell lung cancer, in combination with Bristol-Myers Squibb’s nivolumab (Opdivo) or with Merck (MRK)’s pembrolizumab (Keytruda).

The company has said its treatments work best in synergy with others.

Founded in 2008 to commercialize a cancer-fighting approach discovered at the University of Miami, Heat decided Miami wasn’t the right environment to build the company. After exploring several major biotech hubs, it picked the Research Triangle area after meeting with specialists at the North Carolina Biotechnology Center, where it initially rented an office.

NCBiotech also provided Heat its first outside funding, a $225,000 Strategic Growth Loan.

Heat sold 2.5 million shares of stock at $10 a share in 2013 to raise $25 million in an initial public offering. Its stock price plunged more than 50 percent when a Phase 2 clinical trial of its bladder cancer treatment failed to produce positive results in 2016.

Nevertheless, Heat raised more than $33 million from sales of stock and warrants in 2018.

Currently located in Durham, Heat plans moving into new offices and labs in Morrisville in September.

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