IPO “On the Horizon” for Unum After $65M Series B, CEO Says

Xconomy Boston — 

It’s been quite a week for Unum Therapeutics. Just three days after inking its first partnership, the emerging cellular immunotherapy startup has bagged its biggest funding round to date, and an initial public offering may not be far behind.

Cambridge, MA-based Unum this morning raised a $65 million Series B round from a large group of investors—including “crossover” backers, those who typically invest in publicly traded companies. New to the Unum syndicate are New Leaf Venture Partners, which led the round, and Brace Pharma Capital, Cowen Private Investments, Jennison Associates, Novo A/S, Sabby Management, Sectoral Asset Management, and Wellington Management.

Those backers have joined with Unum’s existing investors—Fidelity Biosciences, Atlas Venture, Sanofi-Genzyme BioVentures—in the oversubscribed round. And Seattle Genetics (NASDAQ: SGEN) put $5 million into the round as part of the broad collaboration the two companies announced on Monday.

The company is moving at a fast pace. With the new cash, Unum has now raised some $77 million in two rounds since emerging from stealth last October. And the presence of crossover backers is as sure an indication as any that a startup is at least considering going public. There have been several such Series B rounds this year already from quickly maturing Boston-area biotechs like Jounce Therapeutics, Dimension Therapeutics, and Voyager Therapeutics.

Unum CEO Chuck Wilson confirmed to Xconomy that an IPO is on the radar, noting that the company’s intention in building this type of syndicate was “very much to position this as a crossover round to enable a future public financing.”

“Obviously the feasibility of an IPO will be dictated by continued progress and market conditions, but we do see it on the horizon,” Wilson says. “We’re intending to use the funding to support a number of fully-owned Unum programs through to clinical proof-of-concept—we see [that] happening over the next one to three years.”

The financing round comes just days after Unum snagged its first partner, teaming up with SeaGen in a potentially $645 million deal to develop cellular immunotherapies using antibodies from the Seattle company.

Unum is part of the fast-moving field of T-cell therapy, in which a patient’s own T cells are extracted, genetically engineered to be efficient killers of certain types of tumors, and infused back into the body. Juno Therapeutics (NASDAQ: JUNO), Kite Pharma (NASDAQ: KITE) and others have fast become multi-billion dollar companies on the promise of these therapies, which have produced stunning results in certain types of blood cancers in clinical testing.

Unum’s twist on the concept is a more universal type of approach. It engineers T cells with a surface protein that helps them latch onto a wide array of antibodies, which themselves act as beacons to find tumors and light the way for the killer T cells to follow. The proposed benefit of this approach is that it might enable Unum to bring cellular immunotherapy to any cancer in which antibody therapies are being applied—like solid tumors, for instance, a tough technical challenge companies in the field are trying to overcome.

Unum’s plan for this technology is to string deals together with antibody specialists. The company doesn’t intend to make its own antibodies in-house, but rather align with various companies that want to enhance their experimental antibody drugs. SeaGen was the first example; the two companies are developing two products that harnesss both of their technologies, with SeaGen having the option to potentially add a third product into the fold.

Wilson wouldn’t disclose the targets the two companies are considering, but said Unum and SeaGen are “thinking broadly” about blood cancers and solid tumors.