CARLSBAD – Primmune Therapeutics is poised to launch and potentially see early results from a Phase 2 study this year for its oral immunotherapy to be used in combination with standard care therapeutics for solid tumors.
Primmune’s immunotherapy pipeline is centered on PRTX007, a small molecule-based drug that activates toll-like receptor 7 (TLR7), a protein that plays a crucial role in the body’s innate immune system.
TLR7 is primarily expressed on cells that recognize RNA strands in the bloodstream that are only present in the event of an illness like cancer. According to Primmune Director and CEO Charlie McDermott, PRTX007 has shown early signs of using TLR7’s relationship to those RNA strands to activate the body’s immune system and aid in its response.
“People have been trying to have drugs that turn this receptor on for almost four decades,” McDermott said. “And the problem is, when you do it systemically, you typically cause a lot of unwanted systemic inflammation.”
‘Trench Warfare’ for Financial Backing
Primmune announced last month that it raised $8.6 million in additional Series B funding, bringing the company’s total Series B raise to $23.3 million.
That financial backing will enable the company to start its first proof-of-concept study with 24 patients this year. According to McDermott, the company plans to close additional funding deals later this year that would enable Primmune to double the size of its study to 48 patients.
While Primmune has been in business since 2017, the company is one of countless drug developers and other biotechs that have struggled through multiple years of a challenging funding environment in the fallout of the COVID-19 pandemic.
According to McDermott, all seven of Primmune’s staff members took “significant” personal financial hits to keep the company afloat during the company’s previous clinical trial monitoring the immune response prompted by PRTX007 in healthy patients.
“It was very, very much trench warfare to crawl forward and build up enough data where people were ready to commit,” to supporting the company, he said.
Now on the other side of that struggle, Primmune is in a position to add to its staff. The company announced in early February that Dr. Andrew Sharabi, a board-certified radiation oncologist and a researcher with the UC San Diego’s Department of Radiation Medicine & Applied Sciences, has joined Primmune as its chief medical officer.
The company also formed a Melanoma Clinical Study Advisory Board to support PRTX007’s continued clinical development, including medical oncology experts from Chicago and Australia, where Primmune is conducting its current study of PRTX007.
“Our Melanoma Clinical Study Advisory Board members have deep expertise in immuno-oncology and have been part of practice changing studies for treating melanoma as well as head and neck cancers,” Sharabi stated. “Together our goal is to have Primmune execute a highly impactful Phase 2 study that advances the standard of care and improves outcomes for patients with melanoma.”
Expanding Reach of Immunotherapy
While Primmune’s initial indication for PRTX007 is in the treatment of melanoma, the company intends for the immunotherapy to eventually support treatment for multiple forms of cancer.
The company believes PRTX007’s ultimate utility will be in activating the immune system as a means of improving the response rate to PD-1 therapeutics, which enable T cells in the body to recognize and eliminate cancer cells.
“A lot of patients don’t respond to this therapy; if they respond, they usually do quite well, but their immune system is not really engaging,” McDermott said. “So we believe this systemic TLR7-based activation of the immune system on top of (PD-1 therapies) will drive better response rates and potentially better outcomes.”
Primmune Therapeutics
FOUNDED: 2017
CEO: Charlie McDermott
HEADQUARTERS: Carlsbad
BUSINESS: Clinical-stage immunotherapy developer
EMPLOYEES: Seven
FUNDING: Over $50 million
WEBSITE: primmunerx.com
CONTACT: [email protected]
NOTABLE: Rather than licensing the science of PRTX007 from a research institution, Primmune co-founders Stephen Webber and James Appleman created the compound in-house.
Eli is an award-winning reporter primarily covering the tech and life sciences industries. He previously worked as the San Diego City Hall reporter for the regional wire City News Service. He has also covered public health, transportation and state and local politics in the San Francisco Bay Area for Local News Matters, the nonprofit arm of the regional wire Bay City News Service, where he also oversaw the development and daily content management of the outlet’s public health and COVID-19 news and resource webpage. He is also a contributing writer covering Minor League Baseball for the analysis and commentary website Baseball Prospectus. Eli is a graduate of San Francisco State University and a native of Northern California.
