Langer, Robert "Bob"
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Langer traces his scientific origin story to postdoctoral work with Judah Folkman on anti-angiogenesis — the idea that cutting off a tumor's blood supply could starve it, a concept so unconventional at the time that their foundational 1976 paper was rejected by Nature before being accepted by Science (and vice versa for a companion paper), producing real depression and self-doubt despite what he now recognizes as good work. That research required two linked inventions: a bioassay to actually measure slow (months-long) blood vessel growth, which hadn't existed before, and a polymer-based system capable of releasing large protein molecules steadily over that same long timescale, which also hadn't been done. He traces the 28-year, multi-billion-dollar path from that 1976 discovery to Avastin's 2004 FDA approval (now one of the best-selling cancer/eye-disease drugs in history) as a case study in how long translational science actually takes, involving many labs and companies building on the original isolation techniques. Langer describes the drug discovery process as irreducibly multi-step and only partly systematic — sometimes researchers understand the biological pathway they're targeting, sometimes it's genuinely "shooting in the dark" — spanning theory, novel measurement techniques, substance isolation/purification, and then safety and efficacy testing first in animals and then through phase 1 (safety), phase 2 (efficacy, small scale), and phase 3 (efficacy and safety, large scale) human clinical trials, which he identifies as by far the largest cost driver behind the roughly $2 billion price tag of bringing a new drug to market.
On drug delivery specifically, Langer defines the field as getting a drug to the right place, at the right dose, safely, and identifies core open challenges as cell-specific targeting (e.g., hitting only cancer cells), crossing biological barriers (oral insulin, the blood-brain barrier), and building "smart" systems that respond to physiological signals — citing his own work encapsulating insulin-producing beta cells so they're immune-protected while still sensing glucose and secreting insulin in response, and "intelligent microchips" that can release drug on an external signal. He is cautiously optimistic that AI could meaningfully accelerate drug discovery, particularly in finding chemical-structure patterns across high-throughput screening data (distinguishing what makes some of 10,000 tested compounds work and others not) to guide the next generation of candidates, while noting cost remains a major constraint on adding technological sophistication to delivery systems. On tissue engineering — building organs or tissue from scratch, a field he co-founded with Jay Vacanti using a scaffold-plus-cells approach (the scaffold likened to a "canvas" on which cartilage, bone, stem, or other cells are grown) — he reports that engineered skin is already FDA-approved for burn victims and diabetic ulcer patients, blood vessel and other tissues are in various stages of clinical trials, and discusses immune rejection solutions ranging from encapsulation (protecting transplanted cells from immune attack, as in his "artificial pancreas" work with Dan Anderson) to gene-editing approaches that make cells less immunogenic, to simply using a patient's own cells.
Asked for the most beautiful scientific idea he's encountered, Langer points to CRISPR — bacteria's naturally evolved mechanism for destroying viruses, repurposed as a gene-editing "cut and paste" tool — while cautioning that applying it to fix whole-body problems remains exceptionally difficult, and that medicine typically advances stepwise (e.g., engineering an easier intermediate like an improved CAR-T cancer-killing cell rather than jumping straight to whole-organ or whole-brain fixes). He is measured on near-term impact on human longevity (expecting better and somewhat longer lives in specific areas rather than a "radical increase") and expresses confidence cancer will eventually be cured through a combination of biological understanding (genetic and immunological mechanisms) and engineering (delivery, targeting, and manufacturing), while resisting any specific timeline. On the patent system, he argues it's essential despite its downsides — without patent-backed exclusivity, the roughly $2 billion required to develop a new drug would never be raised — and walks through the disclosure-to-USPTO patenting process at MIT. On what makes his 40+ co-founded biotech companies (collectively valued in the tens of billions) succeed, he emphasizes that strong business leadership matters as much as science, that a good scientific "platform" (broadly applicable technology, validated in animal models, with strong patent claims) is necessary but not sufficient, and lists concrete business criteria for sequencing which application to pursue first: market size, availability of good animal models, feasibility of clear-endpoint clinical trials, competitive landscape, reimbursement prospects, and manufacturing feasibility.
On running one of the world's largest academic labs (over 100 researchers, $10M+ in annual grants), Langer credits simple but genuine motivators — researchers feeling their work matters and seeing real progress — as the key to morale, notes he sources major lab priorities both organically (his own or students' ideas) and externally (requests from the Gates Foundation, Juvenile Diabetes Foundation, and similar funders), and takes pride most of all in the roughly 1,000 students who've passed through his lab, many now in the National Academy of Engineering or Medicine, university presidents, or company CEOs — comparing them to his own children. Reflecting on philanthropic funding strategy, he observes that major funders (contrasting David Koch's personal-experience-driven focus on cancer with Bill Gates's more calculated focus on developing-world health) start from a defined vision and then seek out the best people or labs working toward it, and argues academia benefits when departments take chances on unconventional, cross-disciplinary hires (citing MIT's hiring of Giovanni Traverso, a physician-engineer straddling gastroenterology and mechanical engineering) rather than forcing candidates into narrow disciplinary "buckets."
Excerpts
On the emotional toll of early rejection despite ultimately being right:
“When we got the rejections, it was really upsetting. I thought, you know, I did some really good work, and Dr. Folkman thought we'd done some really good work... you feel multiple emotions — one is being sad and being upset, and also being maybe a little bit angry because you feel the reviewers didn't get it. But then, as I thought about it more, I thought, well, maybe I just didn't explain it well enough.”
On why cutting off a tumor's blood supply works:
“It's kind of like a war, almost — if the nutrition is going to the tumor and you can cut it off, you starve the tumor and it becomes very small. It may disappear, or it's going to be much more amenable to other therapies, because it's tiny — chemotherapy or immunotherapy is going to have a much easier time against a small tumor than a big one.”
On what makes a startup succeed beyond the science:
“I actually think that really the most important thing is probably the business people... when I look back at the companies that have done well, it's been because we've had great business people, and when they haven't done as well, we haven't had as good business people... the business aspects are: you have to be a good judge of people, you have to be strategic, you need a good FDA regulatory and clinical trial strategy, and you have to be able to raise money.”