kinds of targeted protein molecules that can bind with a variety of different targets, Pfeffer says. Jounce isn’t disclosing specifically what those molecular targets are, but Pfeffer said they come from three main categories—checkpoint inhibitors, co-stimulatory molecules, and those in the tumor microenvironment.
The first category, checkpoint inhibitors, is where immunotherapy evangelists have had the most success. Bristol-Myers’s drug ipilimumab (Yervoy) falls into this camp, as a drug that inhibits a target called CTLA-4, which acts like a brake on the immune system. The drug, designed to release that brake and allow an immune attack on tumors, has shown an ability to help people live longer with melanoma. It has also been a commercial success, as the drug generated $706 million in worldwide sales in 2012, its first full year on the market, and saw 47 percent growth in the most recent quarter.
Bristol-Myers is following up on that success with an experimental drug called BMS-936558, which homes in on a target called PD-1. That drug showed some impressive ability to shrink tumors in a study of 240 patients released at last year’s American Society of Clinical Oncology meeting. One oncologist from Johns Hopkins, Julie Brahmer, told Bloomberg News at the time that PD-1 acts like an “invisibility cloak” tumors use to avoid an immune system attack.
Jounce’s scientific founders believe that there could be more of these sorts of cell checkpoint inhibitors, Pfeffer says. Yervoy and the anti-PD-1 drug are “the tip of the iceberg,” he says.
The second type of treatments on Jounce’s radar are co-stimulatory molecules. If checkpoint inhibitors are drugs that release a brake on the immune system, then co-stimulatory molecules are ones that essentially push down on the immune system accelerator pedal.
Lastly, Jounce is concentrating on the tumor microenvironment, and which molecular switches might be involved in rendering tumors “open” for immune system surveillance and attack, and which ones make tumors “closed” off. Gajewski brings considerable expertise in that particular area of immunotherapy, Pfeffer says.
The work here is at very early stages by biotech industry standards. Jounce has obtained, and is in the process of obtaining, licenses to develop technology from the institutions where its scientific founders work. The company has just under 10 employees, and will now set out to build up a bigger team of people with expertise in tumor immunology, antibody drug discovery, translational science, and early drug development, Pfeffer says.
There are lots of competitors seeking to build expertise in various aspects of what Jounce is trying to do. Bristol-Myers Squibb is the “big gorilla” in the field, and Merck has an immunotherapy molecule as well, Pfeffer says. Other smaller players in the field include Seattle-based Oncothyreon (NASDAQ: [[ticker:ONTY]]), Denmark-based Bavarian Nordic, and Seattle-based VentiRx Pharmaceuticals, which recently struck a partnership with Celgene (NASDAQ: [[ticker:CELG]]).
For those willing to stretch the definition of immunotherapy a bit, you can also consider standard antibody drugs like Genentech’s trasztuzumab (Herceptin) and rituximab (Rituxan) as members of the class, because scientists know they tend to work in part through antibody-dependent cellular cytotoxicity (ADCC) which essentially means the drug stimulates an immune response to tumors.
What’s different about Jounce, Pfeffer says, is that it’s attempting to cast a wide net around a variety of technologies and approaches, rather than bet the farm on just one drug or biological target. By casting a wide net, Jounce could be attractive to partners from its early days. Even before the company issued its first announcement that it was in business, Jounce got a number of inquiries from people who want to talk about collaborating, Pfeffer says.
“What’s exciting to me, as business development professional for 20 years, is the amount of inbound interest from larger companies interested in the space. It’s really been off the charts, even before we launch the company,” Pfeffer says. He adds: “There are a lot of small companies out there, and big companies out there. But what folks are doing today is the tip of the iceberg, and there’s plenty of opportunity.”
