Investors bet big on Feng Zhang’s new startup, out to solve one of gene editing’s most vexing problems
Ryan Cross/Boston Globe / February 16, 2023

Months before Feng Zhang met with a trio of investors from GV, the venture capital arm of Google’s parent company Alphabet, the scientist had been dropping hints that his lab at the Broad Institute of MIT and Harvard was working on something big. When he sat down for dinner at the Liberty Hotel in the summer of 2021, he was finally ready to talk about it.

By the time the group finished appetizers, Zhang had convinced the table that he may have devised a new solution to one of the most vexing problems in biotech: how to deliver potentially curative genetic medicines to hard-to-reach parts of the body, such as the brain, heart, and muscles.

The outcome of that dinner was a new biotech startup, founded by Zhang in the fall of 2021. After a year-and-a-half of working in stealth, the company, Aera Therapeutics, formally launched Thursday morning with $193 million in financing from GV and other investors, including ARCH Venture Partners and Lux Capital.

The Boston company is devising a new nanoparticle technology based on previously overlooked human proteins that assemble into virus-like structures. With a little tinkering, Zhang showed that they can be used to sneak medicines based on the genetic molecule RNA into human cells grown in a dish.

If Aera’s approach works in people, it could broaden the reach of genetic therapies, which currently have limited clinical applications — partly because there aren’t enough methods forgetting those medicines to hone in on the right cells.

Aera’s launch comes during a period of economic turbulence that has made it hard for some biotech startups to raise money to continue developing their therapies and test them in clinical studies. But Aera’s investors appear to be playing the long-game, wagering that Zhang’s new technology could make waves even though it is likely several years away from being tested in humans.

“It is very early science, but super exciting, and if it works, very transformative," said Issi Rozen, a venture partner at GV who knew Zhang well from his prior position of chief business officer at the Broad Institute. “This is a company that we knew would need to mature over the next few years and develop the value of its technology. And we’re willing to wait and build it right."

Aera won’t disclose any specific diseases that it is working on, or even tip its hand to the parts of the body that Zhang’s new delivery technology might conquer. “I think it’s premature for us to be thinking about applications," said chief executive Akin Akinc.

That a biotech company can raise so much money when tangible ideas for therapies are so far away is partly a reflection of the vast potential a new delivery technology would have, and partly a statement of trust in the technology’s creator.

Zhang made a name for ­himself as one the inventors of CRISPR gene editing, a technology that promises to revolutionize treatments for cancer, genetic diseases, and more by making precise and permanent changes to the human genome. Several Boston companies, including ones founded by Zhang, are already developing CRISPR therapies, and the first medicines based on the gene-altering technology may be approved within the next year.

Many gene editing companies are focused on editing blood or immune cells, since they can be readily removed from the body, altered in the lab, and reinfused. Others are working on editing cells in the liver, since therapies delivered by engineered viruses or lipid nanoparticles — the mainstay delivery vessels of genetic medicine — tend to get stuck in that organ after infusion.

But in order for CRISPR to reach its full potential, Zhang felt there was an “urgent need" to develop new delivery strategies. “Delivery is the major bottleneck," he said.

After reading about an intriguing human protein that could form virus-like structures, Zhang’s team began a fishing expedition through the human genome looking for similar proteins that could be harnessed to package and deliver genetic material.

The results of that search led to the discovery of one especially useful protein that became the backbone of a new nanoparticle technology, dubbed SEND, which was published in the journal Science soon after Zhang’s dinner with the GV investors. Aera has licensed the SEND technology, along with new gene-editing enzymes discovered in Zhang’s lab, from the Broad Institute.

The fact that the proteins used in SEND are made in the human body is key, Rozen said, because it suggests that our immune systems will be less likely to reject it, hopefully making it easier for the therapy to slip into cells undetected.

Aera will likely focus on diseases that can’t be treated by editing the liver or by removing cells from the blood. “There’s so many other tissues that are completely unsolved, and if we could do something there, it would really move the entire field forward," Akinc said.

The startup has about 50 employees and sublets a lab from Vertex Pharmaceuticals in Boston’s Seaport. Akinc said that he plans to add 30 people to Aera this year and move the company to Kendall Square, the biotech hub of Cambridge.

Until recently, Akinc spent 20 years at Alnylam Pharmaceuticals in Cambridge, where he helped pioneer the development of RNA medicines that can silence disease-causing genes in the liver. One of the major hurdles for that new class of drugs was figuring out how to deliver them into cells safely.

Aera reminds him of the early days of Alnylam, and he hopes to replicate the success there at his new company. “I’m hoping to do it all over again," he said.

[ More on Maraganore ]

Startup raises $135m to test therapies for rare bleeding disorders
Ryan Cross / Boston Globe / February 20, 2023

A biotech startup with operations in Cambridge has big plans to develop medicines for bleeding disorders it believes have been neglected by the drug industry. On Tuesday morning, Hemab Therapeutics said it raised $135 million to fund clinical studies of its first two drugs.

Other biotechs have recently made strides in developing potentially permanent therapies for two kinds of hemophilia, inherited diseases in which people lack crucial clotting factors needed to stop bleeding. But chief executive Dr. Benny Sorensen said he hopes to make Hemab “the ultimate company" focused on all other bleeding and clotting disorders beyond hemophilia.

The startup raised an initial $55 million in 2021. Its new financing comes amidst an economic downturn for biotech companies, many of which are struggling to raise large funds that came easily a year or two ago.

John Maraganore, chair of Hemab’s board of directors, said private investors were ready to chip in more than $200 million to the company, but the startup opted for the lower sum that will carry Hemab into 2025 and help it generate data needed to begin pivotal clinical trials.

“It’s just remarkable to see that happen in this environment, and I think it reflects the recognition that Hemab’s science and team can really be disruptive," said Maraganore, the former founding chief executive of Alnylam Pharmaceuticals in Cambridge.

Hemab’s first therapy is for a rare bleeding disorder called Glanzmann Thrombasthenia, which the firm estimates afflicts about 25,000 people worldwide. The company’s drug is a bispecific antibody that helps recruit a clotting factor to the site of a hole in a blood vessel to stop bleeding.

That compound is being evaluated in an early stage study, and Sorensen hopes it can help prevent bleeds when given to patients as a prophylactic. Initial results from the study are expected later this year, and if positive, the company will use its new financing to start a larger clinical trial.

Hemab’s second therapy is an antibody designed to restore normal clotting in people with von Willebrand disease, which as many as 1 in 100 people have, although far fewer experience severe complications requiring regular treatment. Sorensen said Hemab will start a clinical trial in 2024.

The company believes its drugs could be particularly impactful for menstruating people with these two diseases, where heavy bleeding can be debilitating. “It’s not unheard of that a woman will spend 8 to 10 days at home every month, simply because it is impossible to walk around without bleeding," Sorensen said.

Hemab has 15 employees split between offices in Cambridge and labs in Copenhagen. Sorensen said the firm would more than double in size this year, with the majority of new hires in Cambridge.