Unity's Nathaniel David

Imagine a drug that could clear away "senescent" cells and make the life span allotted to you longer and healthier, absent many of the myriad diseases that can accumulate with age. Some investigators have been working on that subject for more than a decade, and now a biotech is being launched to see if it can make that dream a reality.

That's a tall order. But a new preclinical mouse study that's being published today in Nature concludes that regularly scrubbing the body of these nondividing cells that accumulate with age--like dust in the attic--can tamp down on chronic inflammation, delay tumors and preserve organs and tissue threatened by our increasingly frail bodies.

Investigators brought in a cellular dust mop called AP20187, a compound that extended the age of mice by 17% to 35%. And a biotech dubbed Unity Biotechnology, based in the big San Francisco hub, has taken on the task of developing new therapies that can do the same for humans.

Unity isn't saying just how much the startup round will be. But the financial backers are some of the best known in the biotech business. Founding investor ARCH Venture Partners, which helped launch Juno to fame in the immunotherapy world, led the round. Venrock, WuXi, Mayo Clinic, Unity's management team and "others" are listed as key players.

ARCH co-founder Robert Nelsen tells me that the group is staying mum about the money for now as they put together a "large" round. We'll keep you posted on that part of the equation.

"This has been a long journey, and we're at the point now where we can start making medicines to achieve in humans what we've achieved in mice," said Dr. Jan van Deursen, a scientific co-founder and professor of biochemistry and molecular biology at Mayo Clinic. "I can't wait to see what happens as we move into the clinic." Judith Campisi, a professor at the Buck Institute for Research on Aging, and Daohong Zhou, a professor of pharmaceutical sciences at the University of Arkansas for Medical Sciences, are also joining as scientific founders.

The business side of things will be handled by Nathaniel David, a serial biotech entrepreneur and former CSO at Kythera. The rest of the team includes Keith Leonard, executive chairman, who was previously chief executive officer of Kythera (acquired by Allergan last summer for $2.1 billion); Dr. Jamie Dananberg, chief medical officer, previously EVP and head of the Cardiovascular and Metabolic Therapeutic Area Unit at Takeda Pharmaceuticals; and Dan Marquess, chief scientific officer; previously head of medicinal chemistry at Theravance.

David was fascinated by the potential of what van Deursen was working on the minute he saw a paper the scientist wrote on it in 2011. Within minutes, 5 of his colleagues had sent him a copy of the paper. Seventy-two hours later he was sitting down with the scientist.

"I said this is awesome, let's start a company," David tells me, and four years later he still is clearly thrilled by the prospect of what the company can do. At this point, the company has built a staff of 21 working under stealth mode and the backing of ARCH and Venrock. By the end of 2017 he will have 50 on board.

That team will be tasked with setting up clinical trials for how these "senolytic" therapies can address specific diseases, with an eye to proving that they can halt disease progression or even roll back the damage that's been done by ailments like glaucoma or osteoarthritis.

There are clearly some big challenges ahead, notes David, who is well aware of the challenge he faces in proving initially that these drugs will not harm people. That will start with multiple studies in various species, with human trials expected some time in the "next few years." (Don't ask for a timeline just now.)

Part of the safety equation will revolve around the therapeutic strategy. Dosing will be limited to a specific treatment area, such as the eye for glaucoma.

Aging is a fascinating research subject, but it's no arena for dilettantes. Google has made a splash in the field with its upstart Calico, which has also made aging its primary concern. But there's a long journey between mouse studies and human studies.

A story in The Atlantic, out today in conjunction with the new study, notes that senescent cells may sound like an unnecessary nuisance, but they also carry out some important tasks. Making sure that the youthful-looking mice created in the lab experiments aren't caused by compounds that also spur cancer in humans will require some painstaking research.

- here's the release