HIV biotech Calimmune bags $15M to move one-time gene therapy into new trials

After getting started 9 years ago with backing from angel investors, Calimmune just landed a $15 million B round, positioning the biotech to launch new trials with a gene therapy designed to durably stymie the lethal HIV with one treatment.

Alexandria Venture Investors joined with RA Capital Healthcare Fund and Translational Accelerator--two earlier investors--to back Calimmune, which is based in Tucson with facilities in Pasadena, CA, and Sydney, Australia, where Calimmune recruited a group of top investigators who were cut loose by Johnson & Johnson ($JNJ).

Calimmune, which has been backed by California's stem cell agency CIRM, has been working on Cal-1, looking to insert a gene that slashes the production of CCR5, a protein which is found on the surface of white blood cells. By reengineering patient-derived CD34-positive stem cells and CD4-positive T cells, which are reinfused after they're adapted, the company is looking to provide patients with a mix of short- and long-term protective treatments. And initially they'll be focused on patients who can't tolerate the current generation of cocktails used to keep HIV in check. 

Simply put, says CEO Louis Breton, this new therapy is designed to equip the immune system to "stave off the effects of HIV converting to AIDS," a threat to tens of millions of people around the globe.

CCR5 is a well-known target in the HIV R&D world. About one in 100 HIV patients are protected by a mutation that prevents them from producing CCR5, which HIV uses to get into T cells. The biotech wants to slam that door shut with a single treatment which is also designed to prevent viral fusion, another part of the infection process. And it got started with research from the labs of such notables as David Baltimore at Caltech, Salk's Inder Verma and Irvin Chen from UCLA.

Initially, the plan is to mount four Phase I/II studies with 5 to 15 patients each over the next 20 to 24 months, looking for a clear snapshot on safety along with insights into fine-tuning the cell strategy and finding the best approach for a later pivotal study.

Calimmune hasn't had much of a profile outside of the HIV world, but Breton is looking to change that. The company has a staff of 40 now, he says, and is looking to expand and possibly strike a partnership deal with a Big Pharma in the space. And unlike some of the leading gene therapy companies in the industry which are targeting tiny populations, Calimmune is tackling a treatment for a disease with a huge, global population of patients. Discussions about million-dollar therapies, he says, won't work for something like HIV.

"Our mission," says Breton, "is to provide broad capacity; democratize gene therapy for the masses."

- here's the release

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