(FORTUNE Magazine) – OF ALL THE REASONS bright people once chose careers in biology, getting rich surely was not one of them. The challenge of unraveling life's deepest mysteries -- and the tantalizing chance for a Nobel Prize -- was attraction enough. But rapid-fire breakthroughs in genetic engineering in the past decade have led to an astonishing array of new products. Many of these products are being turned out by relatively small companies founded by scientists. None of the biologist-entrepreneurs profiled here had given business ten seconds' thought when they began their careers. Some swapped lab coats for pin stripes with ease, plunging into a new world of money raising and dealmaking. Others endured repeated bouts of soul searching. But they have one thing in common -- they all became molecular millionaires.

STEVEN GILLIS CHRISTOPHER HENNEY Immunex Corp. Seattle, Washington By any measure, immunologists Christopher Henney and Steven Gillis are an odd couple. Age, nationality, and temperament separate them. Science and business bind them together. Henney, 46, is a reflective Englishman who enjoys sweaty sports like soccer or squash. The hard-charging Gillis, 34, an American, prefers a round of golf, though he rarely has time. Both are experts on Interleukin-2, a cancer-fighting compound manufactured in minute quantities by the body's immune system. As founders of Immunex, a six-year-old company devoted to exploiting the potential of Interleukin-2, they have seen the combined value of their stock rise to more than $13 million. They met in the late 1970s at Seattle's Fred Hutchinson Cancer Research Center. Although Henney had recruited Gillis and outranked him in the institute's pecking order, the two hit it off and agreed to collaborate on experiments. ''We didn't care who was going to get the credit,'' recalls Gillis. ''We just wanted to get the work done and worry about the Mickey Mouse stuff later.'' Their research soon attracted commercial attention, and venture capitalists besieged them with tempting offers. In 1981 they resigned to start Immunex. Their reasons for going into business were wildly different. Gillis, then at the height of his creative energies, was fed up with what he calls the political atmosphere at Hutchinson. ''I was more concerned with getting the research done,'' he recalls. ''I wanted to make Interleukin-2 molecules and find out if they were worthwhile. At the center you never get to carry anything through to fruition.'' Henney, who was turning 40, had more personal motivations: ''I couldn't see myself doing the same thing for 25 more years. Some guys get their hair permed, put gold chains around their neck, and go chase girls. I decided to start a company.'' Neither foresaw how quickly Immunex would acquire a life of its own. Says Henney: ''I saw us as a research outfit. We would do what we wanted scientifically, and big companies would support us. It would be fun.'' But | they soon realized that to survive, the company would have to make and market products as well as dream them up. The daily pressure transformed their roles in the business. Despite his love of research, Gillis found he had little time for his own work. ''I've become a cheerleader and a cajoler,'' he says. ''I walk around the lab asking people what's new.'' Henney, who started out as chief recruiter of talented scientists, became more involved in structuring deals. When Immunex went public in 1984, both had to come to terms with sudden wealth. Says Henney: ''Initially I tried to dismiss it. I worried about being on an emotional roller coaster, worrying about how much money I made or lost every day. Then it slowly dawned on me that it's not going to go away. You need to have your feet on the ground to handle that.'' Gillis experienced similar doubts: ''Some days I thought that if somebody stuck my resume in front of me and asked, 'Are you worth this much money?' I'd have to say no. On other days I'd say, 'Damn right. I worked hard and took a giant risk, and I'm delivering on the promises I made.' ''

WILLIAM RUTTER Chiron Corp. Emeryville California ''Science is a grand game. I like the idea of throwing the ball deep and having somebody on my team catch it,'' says molecular biologist William Rutter, 59, who scored one of the first touchdowns in genetic engineering. Ten years ago, when few people saw anything practical in the field, a Rutter-led research team at the University of California at San Francisco endowed bacteria with the ability to make unlimited supplies of pure insulin. That triumph transformed biotechnology from the realm of science fiction to one of science fact. Today, as the chairman of Chiron, a biotech company in the suburbs of San Francisco, the graying but trim Rutter wants to throw more long bombs. A self-described Orientalist, Rutter was born in Malad City, Idaho. The son of a grocer, he went to Harvard to study chemistry. But a fascination with the mysteries of life and evolution drew him toward biology. He earned a Ph.D. at the University of Illinois. ''The most compelling question I could think of was: How does biological development occur? The answer affects our understanding of what life is,'' he says. Rutter grew with his field. In the past 26 years his name has appeared on 267 publications in biochemistry and molecular biology, and he is now director of the University of California's Hormone Research Institute. In another era Rutter might have remained an academic, with plenty of time to pursue his hobbies: collecting Asian Indian miniature sculptures and studying the art and music of ''peculiar peoples and strange societies.'' But as his own research spurred the formation of biotech start-ups, Rutter decided that he had to come to grips with going into business himself. ''The best people in my lab were being recruited by other companies,'' he says. ''It became obvious that I had to get in or lose out.'' In 1981, along with two key collaborators, Edward Penhoet and Pablo Valenzuela, he founded Chiron (the name of the wisest of the centaurs in Greek mythology). Two years later the company went public. Rutter's stock is currently worth $25.4 million. As chairman of Chiron, Rutter delegates much of the daily decision-making to others. But he goes to great lengths to spell out the company's long-term goal: to develop what he calls ''products of real value.'' Says he: ''One of the great romances of this business is to make things that happen in the laboratory actually work for human beings.'' For starters, he wants Chiron to become a leader in developing genetically engineered vaccines. He also wants to help people live longer by altering the molecules that govern functions of cells. Rutter's final aim is still in the realm of science fiction. He hopes to design synthetic molecules that can change basic biological processes, such as speeding up healing of a wound or improving memory. ''It's one aspect of the field that is Jules Vernian,'' he says. ''Except he didn't know about molecules. The truth is, whatever you can visualize will eventually happen.'' Talk about throwing the ball deep.

DONALD GLASER Cetus Corp. Emeryville California When he is not out hiking, sailing, kayaking, scuba diving, or otherwise recharging his batteries, Berkeley Professor Donald Glaser, 61, likes to break scientific logjams. That penchant has brought him glory and riches. As a young physicist he became frustrated when he tried to observe the tracks of atomic particles. So he invented the bubble chamber, which allows scientists to do exactly that, and won a Nobel Prize for it. Switching to molecular biology in the 1960s, he grew irritated with the slow pace of experiments and designed an apparatus to screen thousands of culture plates automatically. This microbe machine ultimately proved less important to scientists than the bubble chamber, but it made Glaser wealthy. In 1971 he became a founder of Cetus Corp., arguably the very first biotech company. Still the company's largest individual shareholder, he owns stock worth nearly $14.6 million. Son of a Cleveland dry-goods storekeeper, Glaser had two passions in high school: science and music. As a teenager he played the viola in the Cleveland Philharmonic Orchestra, and he still calls himself ''a former professional musician.'' By the time he graduated from Case Institute of Technology, science had won. ''It looked as though it would be better to be a fairly successful physicist than a fairly successful musician,'' he says. Glaser was studying cosmic rays at the University of Michigan when the first glimmerings of the bubble chamber came to him. When he moved to Berkeley, his interests switched from basic particles of matter to fundamental molecules of life. He helped start Cetus, he says, because ''I was convinced that the company could do something useful for the world. Everybody knows someone who has died of cancer.'' Glaser never intended to work full time at Cetus, and he never has: ''My freedom to switch to a field I find exciting is something I get by remaining a professor.'' Two years ago Glaser drifted away from molecular biology to neuroscience. ''I'm trying to understand the human brain, specifically how the human visual system works,'' he says. ''I was always intrigued by the way my kids could pick out shapes, even when they were turned upside down. I want to learn the architectural tricks that let the brain do in an instant what today's computers can't touch.'' Glaser says his wealth does not distract him. He has lived in the same house for 20 years and still walks to his office on the Berkeley campus. ''Most of us who founded the biotech industry have more money than we really need,'' he says. ''I'm always trying to think of a way to use it for some social benefit. I've given a fair amount to scientific research in fields I felt were undersupported by the government.'' He admits to a new love for nature photography in exotic places: ''It goes beautifully with my interest in scuba diving. For ten years I was in charge of the scuba program at the university, one of the few faculty committees I chaired.''

PATRICK C. KUNG T Cell Sciences Cambridge Massachusetts He has no memories of mainland China, which his parents fled when he was a | baby. But Patrick Kung, 40, smiles when he recalls how, as a boy in rural Taiwan, he tramped through fields in search of chirping crickets. Today Kung listens to their scratchy symphony from the deck of his new home in a woodsy suburb of Boston. The sounds are sweet for Kung, now a millionaire. Less than two decades ago he borrowed $2,000 to attend the University of California at Berkeley. Says he: ''I guess I've proved America is still a very special place.'' Kung, who became a U.S. citizen in 1981, combines a scientist's vision about the future of biotechnology with an immigrant's passion for piling up wealth. After leaving MIT in 1977, he became a pioneering researcher in biological compounds called monoclonal antibodies, first at Johnson & Johnson's Ortho Pharmaceuticals division and later as a vice president of Centocor, one of the most successful biotech start-ups. Monoclonal antibodies seek out and attach themselves to foreign substances in the body. They are used as therapeutic drugs and in diagnostic tests. Johnson & Johnson's Orthoclone OKT3 (the K stands for Kung), which helps prevent rejection of kidney transplants, was the first monoclonal drug to win approval from the U.S. Food and Drug Administration. ''My track record in the field hasn't been broken by anybody,'' he says. Following his breakthrough at Johnson & Johnson, Kung rewarded himself with a new Mercedes. Deluged with job offers, he jumped to Centocor, then a struggling young company. ''Right after I started,'' he says, ''my paycheck bounced a couple of times, but I came out smelling like roses, considering that my stock has more than doubled in the last couple of years.'' Centocor filled more than his pockets: ''I went there because I felt I could learn a lot from them, and I did. They gave me the missing half of what is necessary to start a business in addition to scientific knowledge: to learn how to raise money and to understand the importance of putting out products.'' His company, T Cell Sciences, was founded in 1984 to engineer a new generation of diagnostic and therapeutic products based on specialized white blood cells. Called T cells, they respond even faster than monoclonal antibodies to the presence of infection or disease in the body. A lot of investors are betting that T Cell Sciences will succeed. The company's initial stock offering last year was oversubscribed. Kung's 11.8% stake was recently worth $3.9 million. An aggressive opportunist with a gambler's confidence in his instincts, Kung went shopping for scholarships while still in Taiwan and wound up studying biology at Berkeley. While completing a Ph.D. on the anatomy of sea urchins, he decided medical research had more promise. In 1972, at 24, he headed for MIT and a prestigious post-doctoral fellowship. His faculty adviser let him choose between virology, then in vogue, or immunology, a field just beginning to get attention. He picked immunology. ''I remembered the Robert Frost poem about taking the untraveled path. The whole field was just opening up. I sensed it was going to be the next wave of the revolution.'' Earlier than many colleagues, Kung sensed that the revolution was leading away from academia. In 1976 Kung was contacted by a team of doctors who learned he had developed an experimental monoclonal antibody test to diagnose a rare form of leukemia. ''They wanted to use my test before treating a patient,'' he says. ''That really electrified me. I saw it as a turning point. It made me understand why I was interested in medicine. And it pushed me to industry, because I felt in the right situation I could experience these things all the time.'' Like many founders of biotechnology companies, Kung claims he works harder than he ever did as an academic. But he makes time to help the Asian community in Boston. ''Many Orientals excel in science and engineering,'' he says, ''but very few are making it in business, especially high tech. I want to get more young Asian students involved in business.''

ROBERT C. NOWINSKI Genetic Systems Seattle Washington Becoming a scientist was more than a dream for Brooklyn-bred Nowinski, 41. It was an obsession. As a 14-year-old high school student, he volunteered to clean out animal cages at New York's Sloan-Kettering Institute for Cancer Research. On summer vacations he worked at the institute as a lab technician, hanging around from 9 A.M. until 11 P.M. While still an undergraduate at Beloit College in Wisconsin, he published three research papers on immunology. Says Nowinski: ''I was a tremendously inquisitive and driven kid, and I was looking for something. Nobody talked about business in my family. Science is what I latched on to.'' Nowinski was immersed in monoclonal antibody research at the Fred Hutchinson Cancer Research Center in Seattle when the biotech industry latched on to him. The entrepreneurs who sought him out knew less about science than Nowinski did about business. In 1980, on his 25th birthday, David Blech quit his job as a Prudential-Bache stockbroker and, with his brother, Isaac, incorporated a company called Genetic Systems. The Blechs had only the vaguest idea of what it might produce. After reading a magazine article on monoclonal antibodies, they decided the subject looked promising and began searching for a scientist to hire. They called Nowinski cold and persuaded him to meet them in New York. In a matter of weeks he agreed to become the scientific director of Genetic Systems. ''I was really surprised I did it,'' says Nowinski. ''I guess there was some sort of spark in their eyes that I identified with.'' Nowinski, no slouch in the riveting-gaze department, persuaded his whole staff at the Hutchinson Center to join him. The 16-member team was already developing a promising monoclonal antibody product: a diagnostic test for chlamydia, a sexually transmitted disease that affects nearly six million people a year in the U.S. Nowinski's test was easier and faster than previous methods. Even before the product reached the market, six-month-old Genetic Systems went public. On the first day of trading, the stock doubled to $4. ''It was a pretty exhilarating experience,'' says Nowinski, who got one million shares. ''No one in my family had ever owned a share of stock.'' Genetic Systems' first year was a revelation for Nowinski. He recalls, ''I had been totally absorbed with research. All of a sudden I was dealing with stockbrokers, bankers, accountants, and pharmaceutical executives. It gave me a tremendous sense of being in the middle of the world. It changed my values fundamentally.'' He also began to display some business savvy. When a team of Bristol-Myers executives came to his labs to discuss a licensing arrangement, Nowinski sensed a different opportunity. ''Bristol-Myers had always been a licensing company, and they were looking for a way to get into research,'' he explains. ''We were developing products for markets that they were already No. 1 or No. 2 in.'' Genetic Systems' stock was moving up, and Nowinski figured the time was right to sell the company. Bristol-Myers seemed a good fit. ''We negotiated the thing in an evening,'' he says. By the time the investment bankers arrived, the deal was nearly done.'' The final agreement: a stock transaction valued at $300 million. Now a Bristol-Myers divisional vice president, Nowinski continues to head Genetic Systems. ''When the acquisition went through I realized I had enough money to do whatever I wanted,'' he says. ''But I discovered I was really bound to health care, right to my roots.'' Nowinski did use some of his Bristol-Myers dividends to redecorate his Seattle home and to outfit his office with an assemblage of modern paintings, sculpture, and furniture. A pricey Bang & Olufsen stereo sits behind his black and chrome desk. ''When I'm in a good mood, the music pours down the halls,'' he says. ''Lately the Pavarotti has been pretty loud around here.''

WALTER GILBERT Biogen Cambridge Massachusetts One side of Walter Gilbert, 55, is pure halls of ivy. With his unruly hair and horn-rimmed glasses, the Nobel laureate biochemist is the archetypal rumpled academic. Peering over stacks of papers in his Harvard office, he intones, ''My deepest interest is the intellectual play of ideas in the laboratory. Money means very little to me.'' But there is another side to Gilbert, who was a founder and chairman of Biogen, one of the original genetic-engineering firms. ''I very much think of myself as an entrepreneur,'' he says. ''What I enjoy most is the innovative moment. To see a company built out of an idea is very satisfying and gratifying.'' As a precocious youngster in Boston, Gilbert saw very little about business that appealed to him. He was attracted to vistas provided by telescopes and microscopes. At Harvard he studied theoretical physics, then switched to mathematics for a Ph.D. at Cambridge University. Returning to Harvard in 1957 as a professor, he got excited about molecular biology and changed fields again. Gilbert's brilliant work deciphering the chemical sequences of the DNA molecule earned him the 1980 Nobel Prize in Chemistry. Shortly after going to Stockholm to receive the award, he abandoned Harvard to become chief executive of Biogen. The early 1980s were heady for the company, one of biotechnology's best-publicized start-ups. Flush with venture capital, the company established research labs in Cambridge, Massachusetts, and in the European cities where several of its founding scientists worked. Instead of walking to Harvard faculty meetings, Gilbert jetted first class to Biogen's executive offices in Switzerland. ''The experience was very striking,'' says Gilbert. And though Biogen was not making money, it attracted new investors like a magnet. The company went public in 1983. Gilbert and his wife held shares worth $12 million at their peak. Then in late 1984, with Biogen struggling to bring products to market, Gilbert the academic grew increasingly restive about Gilbert the businessman. After a series of disagreements with company executives over his heavy spending on research, Gilbert abruptly resigned and returned to Harvard. ''That whole period,'' he says, ''was a distraction from my deeper interests in science, which are ultimately not the same as the company's.'' But an entrepreneurial bug still circulates through Gilbert's system. He regularly meets with venture capitalists in hopes of raising $10 million for a new biotech outfit, Genome Corp. Its purpose: to analyze the three billion units of DNA that make up the human genetic code. ''It's something I feel needs to be done,'' says Gilbert. ''The major problem is whether the endeavor can be made profitable enough in the short term to support itself.'' Which side of Gilbert will come to grips with the problem? Says the academic: ''I don't expect to run the company. I plan to crank it up, give it a push in the right direction, and look at it every couple of months to see how it's doing.'' Says the entrepreneur: ''I can provide the vision of what it can be, and how it can work.'' Place your bets.