By Jessica Shambora

We struck a nerve yesterday. Our post about a study on consumer perceptions and use of generic drugs ignited a firestorm of comments.

That firestorm came from all directions. Some readers attacked Big Pharma. Others blasted the generic manufacturers. Some commenters hit both.

Dan from Hiram, Maine said, ”After drug companies obscenely cranked up drug prices over the past 5 years, a generic drug at 30-50% price reduction is still vastly overpriced.”

Jeff from Mystic, Connecticut wrote: “Just remember that generic drug makers spend more on lawyers than anything else. They are parasites.”

Tim from Houston, Texas basically defended the major drug companies: “Remove enough of Big Pharma’s revenue stream, and someday in the distant future, there might not be any new drugs to copy.”

But here’s how we really stirred up controversy yesterday: By claiming that generics are identical to brand-name drugs.

Frank from Oregon wrote: “The web is full of stories about people suffering major health problems after switching to generics…They contain the same active chemical. That does not mean the work the same way.”

Ryan from San Diego, California told me to “do my homework…the FDA allows for a 20%-25% Variance in bioavailablity.”

Well, today we went back to Jackie Kosecoff, CEO of Prescription Solutions, the in-house Prescription Benefits Manager (PBM) for UnitedHealth Group (UNH), whose visit sparked yesterday’s Postcard on this very subject. She responds to the debate: “Generics are identical–or bioequivalent–to a brand-name drug in dosage form, safety, strength, route of administration, quality, performance characteristics and intended use. ”

The FDA website echoes Kosecoff’s statement: “A generic drug is the same as a brand-name drug in dosage, safety, strength, quality, the way it works, the way it is taken and the way it should be used. FDA requires generic drugs have the same high quality, strength, purity and stability as brand-name drugs.”

So, in fact, we did our homework (and Ryan, re your point about the variance in bioavailability, this is commonly misunderstood. According to 2004 letter from Dr. Steven Galson, then director of the Center for Drug Evaluation and Research at the FDA and now U.S. Surgeon General, that -20/+25%, “actually represents the acceptable bounds on the 90% confidence intervals around the ratio of the mean result for each of the two products.” He also writes that the average difference in absorption was 3.3% for 127 bioequivalence studies of generic drugs approved in 1997. And a study published in JAMA in December, 2008 found “no evidence of superiority of brand-name drugs to generic drugs.”)

I’m more convinced than ever that confusion about generics — the very point of yesterday’s Postcard — isn’t going away.

“Betting on the Future.” That’s the 2009 theme of Fortune’s Most Powerful Women, who convened in New York City last evening for a mega-celebration and some very smart conversation. I’m not sure I belong on stage with three superstars under 40: Bank analyst Meredith Whitney, Google’s (GOOG) Marissa Mayer, and Goldman Sachs’ (GS) Dina Powell. But there I was (at age 49), talking with them them about how they’ve navigated their careers and how they view the future.

It was an insanely inspiring evening, thanks also to 32 young women from 23 developing countries. This happened to be the last night in the U.S. for these participants in this year’s Fortune/U.S. State Department Global Women Leaders Mentoring Partnership. These international women are nominated by the State Department’s embassies in developing countries and chosen by Fortune to shadow American women leaders each May. Some of this year’s mentors — including Time Inc. (TWX) CEO Ann Moore, Fidelity Personal Investing president Kathy Murphy, American Express (AXP) execs Joan Amble and Susan Sobbott — were with us last evening.

So were plenty boldfaced names: Tina Brown, Nora Ephron, CNBC’s Becky Quick, CNN’s Christiane Amanpour. My Postcards colleague Jessica Shambora sat beside Sheri McCoy, Johnson & Johnson’s (JNJ) Worldwide Pharmaceuticals chairman, who is No. 44 on Fortune’s Most Powerful Women list.

A few Best Moments from the evening:

Best Career Lesson: Mayer, Google’s vice president of search products and user experience, talked about juggling 14 job offers after she graduated from Stanford. She interviewed with Google founders Sergey Brin and Larry Page and guessed that their start-up had “a 2% chance of succeeding,” she said. But she also figured, “I’ll learn more failing at Google” than succeeding at a well-established, stuck-in-its-ways company. She took a risk, And look at where it got her. At 33, Mayer is the youngest person ever to make Fortune’s Most Powerful Women list.

Smartest Industry Outlook: Meredith Whitney, who is No. 35 on our MPWomen list and made Fortune’s cover last August, said that more banks will fail as the economic recovery stumbles and some giants fail to adapt. The survivors: nimble companies that revamp their business models. One that she bets will succeed: American Express. (Click here to see Whitney talking with CNNMoney’s Poppy Harlow.)

Most Dynamic Duo: Gayle King, O magazine editor at large and Oprah Winfrey’s best friend, who brought as her “rising star” guest her daughter Kirby. A 23-year-old Stanford grad, Kirby Bumpus is pursuing her Masters in Public Health — and this summer doing an internship with teens in Harlem, teaching them about sex education.

Most Moving “Greatest Mentor” tribute: Rica Rwigamba, who runs an eco-toursim company in Rwanda, spoke about her mother and drew tears and standing ovations. This charismatic entrepreneur, who was one of the 2009 mentees, told a story about her mother returning to Rwanda after the country’s genocide and finding a new home for her husband and children. After Rika’s tribute, CNN”s Christiane Amanpour, sitting beside her, talked about her “Greatest Mentor.” She started by citing the remarkable success of women in a revived Rwanda today: Women hold 56% of the seats in Parliament. CNN’s chief international correspondent segued into a tribute to her mentor: Ted Turner, who built CNN.

Best Party Crasher: Cecilia Attias, who divorced French President Nicholas Sarkozy in 2007, remarried and has moved to Manhattan. She came with Jocelyne Attal, the former CMO of Avaya who now has her own marketing firm, JAgency. Surprise! Attias’s arrival was particularly dicey since the only dinner seat we had for the former First Lady of France was at a way-in-the-back table. Frantically, we tried to make the necessary switches. We couldn’t do it in time before everyone was seated. I have to say, Attias was lovely and most gracious. She thanked us and said she was thrilled that we were able to accommodate her.

We were happy to have her with us…along with 180 other extraordinary women who define power broadly and reach out globally to try and make the world a better place.

Stay tuned to Postcards for video from the evening. Meantime, have a good weekend!

Another Fortune Most Powerful Woman — a longtime member of our annual Power 50 list — is leaving the corporate world. Susan Desmond-Hellmann, who was Genentech’s (DNA) president of product development, is heading to the University of California San Francisco as chancellor.

Desmond-Hellmann’s departure from business’s upper echelons (She ranked No. 13 on Fortune’s 2008 Power 50 list) adds to the trend of top women execs leaving corporations and deciding not to jump back in. Among the departed: former Procter & Gamble (PG) president Susan Arnold, former Pepsi-Cola North America (PEP) CEO Dawn Hudson, former Yahoo (YHOO) president Sue Decker, and the trio who once were the most renowned women on Wall Street: Sallie Krawcheck of Citigroup (C), Zoe Cruz of Morgan Stanley (MS), and Erin Callan of Lehman Brothers, whose recent leave from her new employer, Credit Suisse Group, is looking like it may be permanent.

All these onetime stars are on the sidelines except Hudson, who recently joined Parthenon Group, a Boston-based strategic advisory, as vice chairman — a three-day-a-week commitment to rachet down her stress level, Hudson says.

This decision by Desmond-Hellmann, 51, isn’t so surprising given Genentech’s fate: in March, Swiss drug giant Roche won a year-long battle to acquire the 44% of the biotech company that it didn’t already own for a whopping $46.8 billion. Chief executive Art Levinson, a Desmond-Hellmann fan who promoted her from clinical scientist to chief medical officer to EVP to president, lost the CEO title and remains chairman. Questions abound regarding whether Roche will be able to retain Genentech’s entrepreneurial culture. That culture has helped Genentech become not only the best company in biotech but also one of Fortune’s Best Companies to Work For.

A onetime practicing oncologist who never imagined she’d climb the corporate ladder, Desmond-Hellmann is returning to her roots. She started her career at UCSF and, she says, “my heart has never left it.” She can’t talk at length about her move until the California Board of Regents approves her appointment. Stay tuned to Postcards next week to hear more from Desmond-Hellmann.

Meantime, have a great weekend!

by Jessica Shambora

For this year’s Fortune 500 issue, senior writer Geoff Colvin and I had the chance to look inside one of the list’s most enduring performers: Johnson & Johnson (JNJ). The New Brunswick, N.J.-based health care giant is notoriously media shy, but in the midst of the economic doom and gloom, the company decided it was time to tell its 123-year story of success. What a story that is. (CEO Bill Weldon helps tell it, too, in a video here)

For starters, here are some financial stats that point to J&J’s strength and stability:

-Last year, J&J’s sales rose 6%, and it jumped six places in the 500 ranking, to No. 29 (amidst 12 solid months of economic decline in the U.S).

-J&J’s profit increased 22% last year even as the 500’s profits dropped 85%. That made J&J the sixth most profitable company in America and the fifth most valuable, ahead of Procter & Gamble (PG), Berkshire Hathaway (BRKB), Chevron (CVX), IBM (IBM), General Electric (GE) and many other great performers.

-J&J still holds its triple-A credit rating solidly — one of only four non-financial companies (with Exxon, Microsoft, and ADP) in that dwindling club.

-J&J stock beat the market last year, falling 8% vs. the S&P’s drop of more than 30%.

The list goes on (you can find more stats in the story). Financial discipline is key to J&J’s success, but it’s only one of five principles that Geoff and I outline in our piece. The others are: focus on the future; let the experts run the business; have a purpose beyond profits; and diversify within a single industry.

This last lesson — diversify within a single industry — was particularly fascinating to study, so I wanted to offer further detail that didn’t make it into the story. After all, this strategy helps explain how J&J grew from a maker of surgical dressings, back when the company was founded in 1886, to a broadly based health care company with three business groups, each large enough to be an industry leader on its own.

Consumer Products includes the items everyone knows, and more of them than most people realize – Johnson’s Baby Shampoo, Tylenol, Neutrogena skin care products and Listerine mouthwash (acquired when J&J bought Pfizer’s consumer business in 2006). The Medical Devices and Diagnostics group supplies operating rooms and doctors’ offices with products including sutures, blood tests and artificial joints. The Pharmaceuticals business sells prescription drugs that include Concerta for attention deficit disorder, Remicade for arthritis, Prezista for HIV/AIDS, and others.

The classic argument for a diversified approach is it reduces risk – as one industry gets hit, another may rise – and that rationale has panned out at J&J, where the percentage of revenue contributed by each business varies from year to year.

Another explanation has to do with convergence of technology across businesses. One of the earliest examples of this kind of innovation at J&J was the drug-eluting stent, a breakthrough for cardiovascular disease, which resulted from a meeting in the 1990’s between engineers from the devices group and scientists from the pharma group.

CEO Weldon also tells the story of some scientists who had hit a wall with the product they were developing. They put their problem up on an internal company site, and that same day they heard from a scientist in another business in a different location. He responded with the answer; it had been the focus of his PhD work.

“We have all this expertise in-house so we can pull on it rather than having to go out and find somebody,” says Weldon.

Last November J&J acquired Omrix biopharmaceuticals and is now exploring the use of the company’s biologic drugs in tandem with J&J’s surgical dressings to help control soft tissue bleeding. Cross-pollination can also benefit consumer products. The company applied scientific advances in sunscreen technology from its research labs to its Neutrogena and Aveeno lines, for example.

A third benefit of J&J’s diverse portfolio of health care businesses is the opportunity to follow customers through their lifetimes and across the company’s portfolio. In J&J’s world, our lives are a journey from Baby Powder to Efferdent.

Similarly, focusing on the patient rather than on any single product is the mission of J&J’s recently formed comprehensive care group. If J&J knows you have diabetes, it can show you the virtues of a OneTouch glucose monitor from the device and diagnostics group, and of Splenda sweetener from consumer products, and of health management software from a recently acquired company called HealthMedia.

In these times, when many companies are struggling for growth and trying to squeeze more value out of existing businesses, they would be wise to follow J&J’s lead: Look for opportunities across a single broadly defined industry.

What other companies have had success with this approach? Please let me know your thoughts and ideas.

“I’m one of these who believes you have so much gray matter in your head. And if you take all your gray matter and you worry about what you can’t control, you’re wasting an awful lot of good gray matter, right?”

–Johnson & Johnson (JNJ) CEO Bill Weldon, in a recent interview with Fortune. The New Jersey-based maker of Band-Aids, knee replacements, and prescription drugs–and a bellwether for the health-care industry–announced mixed first-quarter results today. While quarterly earnings of $1.26 per share exceeded the Street’s  expectations, revenue of $15 billion was down 7.2% from a year ago and fell short of estimates.

Pharma revenues took a hit from an expired patent on anti-psychotic drug Risperdal. So Weldon said that he told employees to focus on what J&J can control: “Let’s worry about the products we have, and let’s go out and make sure we are getting those out to the people who can use our products.” –Jessica Shambora

Photo courtesy of Stuart Cahill

by Clayton M. Christensen and Jason Hwang

It’s strange to think that not long ago, the ability of ordinary people to access a blog like this from a PC, laptop or cell phone was the stuff of science fiction. But the advent of the microprocessor, which simplified computer design and assembly, brought computing out of corporate mainframe centers and into our homes.

The microprocessor was what we call a “technological enabler” of disruptive innovation. Translation: It revolutionized the computer industry by making products cheaper and more convenient.

We’ve studied these innovations in another industry, health care, over the last 10 years. Many technological enablers — in the form of molecular diagnostics, imaging technologies, and myriad drugs and devices — exist in health care. Yet, lower cost and convenience haven’t come.

With our new President now focusing on health care, it’s time to look at why the system seems so broken, and to ask why health care isn’t following the pattern of the computing industry.

Actually, disruption is occurring, but often it’s outside of hospitals and physicians’ practices. These niches can show us how health care might become more affordable and convenient.

First, retail. As we describe in our new book, The Innovator’s Prescription, CVS Caremark’s (CVS) MinuteClinic provides basic care at kiosks in retail pharmacies. These clinics are staffed by nurse practitioners who can administer rules-based diagnostics and predictably-effective treatments like immunizations, strep throat exams and diabetes screenings.

Second, digital data. President Obama’s new budget puts big money behind digitizing medical records — a step toward making health data more accessible to both providers and patients. But in the private sector and apart from hospitals, Google (GOOG) Health and Microsoft (MSFT) HealthVault are already helping patients manage their clinical data by making user-generated health records portable.

Companies are also building online resources to allow patients to review health care providers. Zagat, known for its user-generated restaurant reviews, is partnering with WellPoint (WLP) to build a website that rates physicians.

There is also the giant challenge of disrupting the fee-for-service payment model, which general hospitals and private practices were built on. They profit from patients needing more services, more care, more time in the hospital, and more visits back to the doctor. In other words, they profit only when people are sick. What’s the incentive to provide the excellent, low-cost care that technological enablers make possible?

Here disruption comes from innovative providers like Kaiser Permanente. These providers want to give the best care at the lowest cost because they employ their own doctors and operate their own insurance companies. Their patients pay fixed fees for full services over a given time frame. These providers win by keeping their members healthy and satisfied with their care.

So, get ready, doctors and patients. Disruption is coming soon. And it’s a prescription we all need.

Clayton M. Christensen is the Robert and Jane Cizik Professor of Business Administration at Harvard Business School and co-founder of Innosight and Innosight Institute. Jason Hwang, M.D., is Senior Strategist for the Healthcare Practice at Innosight and Executive Director of Healthcare at Innosight Institute. They are coauthors, with the late Jerome Grossman, M.D., of The Innovator’s Prescription: A Disruptive Solution for Health Care.

Fortune’s No. 1 Most Powerful Woman, PepsiCo (PEP) Chairman and CEO Indra Nooyi, delivered disappointing quarterly earnings this morning and said that the company will close up to six plants and cut 3,300 jobs. PepsiCo stock is down 9% to $56 in midday trading.

Meanwhile, another Most Powerful Woman–a newcomer to the 2008 rankings released two weeks ago–is on a roll. Johnson & Johnson’s (JNJ) Sheri McCoy, No. 44 on our MPWomen list, just got promoted from worldwide chairman of the $12 billion surgical care unit to head of the company’s $25 billion pharmaceutical business. Turns out, J&J’s better-than-expected third-quarter earnings, announced this morning, were powered in part by surgical care’s healthy performance. Growth in medical devices, including surgical care, and consumer products drove J&J’s quarterly profits up 30% to 3.3 billion on revenues of $15.9 billion.

I haven’t met McCoy, but when I saw her speak a few months ago, I was struck that she projects the demeanor of a real leader: smart, self-possessed and charismatic. And while J&J has elevated several women to top positions–vice chairman Christine Poon, who is soon to retire, and Colleen Goggins, who is worldwide chairman of the consumer group and No. 24 on our MPWomen list–McCoy stands apart. A chemical engineer by training, she started at J&J in R&D and moved swiftly up through marketing and general management. More than that, in a company that projects a family-friendly image to consumers but where the top women execs historically have been about toughness and drive, McCoy, 49, is renowned for a warm and caring style. One person who used to work for her is Mari Baker, the CEO of Navigenics, a personal-genetics startup in Silicon Valley: “She keeps pictures of her family in her office and was always quite open about needing to get to her sons’ football games,” says Baker about McCoy, who has three sons. “She set a great example for the women on her team.”

Keep an eye on McCoy. If she delivers good growth in pharmaceuticals, she’s clearly a contender to succeed Bill Weldon as J&J’s CEO. The other likely candidates, I hear, are Nick Valeriani, a 30-year J&J veteran who now heads strategy and growth, and Don Casey, a 23-year vet who chairs J&J’s comprehensive care group. With McCoy, who has worked at J&J for 26 years, there’s a combined 79 years of J&J experience among these CEO contenders. That level of company loyalty–what a rarity!

P.S. Yes, I’m back from two weeks away in California, and so is my “Pattie” sign-off. Tell me if you think the signature is silly–or more importantly, should I should keep it? It’s up to you! Thanks!

“It’s essential for anyone who cares about medical research and health care to begin thinking about the world five years from now — not just the world today. Steps should be taken to leverage this movement — to allocate our capital, both financial and intellectual, for maximum impact in the drive toward cures.”

–Katie Hood, CEO of the Michael J. Fox Foundation for Parkinson’s Research (MJFF). Hood’s words are a rallying cry for anyone who believes they may be susceptible to disease, especially in the case of genetic predispositions.

Yesterday Google (GOOG) co-founder Sergey Brin wrote on his personal blog that he has a mutation of the LRRK2 gene that increases his chances of having Parkinson’s disease. Brin’s mother has Parkinson’s and also has the mutation. Actually, there are few instances where the disease is inherited; this mutuation happens to be responsible for some of those rare cases. Brin is already a donor to MJFF and will likely continue to give in light of this knowledge.

Brin learned about his predispostion through a personal genome analysis conducted by 23andme, the genetic mapping company recently launched by his wife, Anne Wojcicki. Read Pattie’s post about 23andme’s splashy spit party in NYC earlier this month. – Jessica Shambora

What a mix of brains and buzz Tuesday night at Barry Diller’s IAC (IACID) headquarters in Manhattan. Jessica (my partner on Postcards) and I were there for a “23andMe Spit Party,” hosted by Diller and Diane von Furstenberg, Rupert and Wendi Murdoch, and Harvey Weinstein and Georgina Chapman.

Think spit meets splash. 23andMe’s business is personal genetics. So the idea of the party, where colorful chromosone cartoons flashed on giant screens in a Frank Gehry-designed space, was to have guests submit DNA samples to 23andMe. A month or so later, you get a genetic analysis — health profile or ancestry or both — in return, for $399. Claiming that advanced genotyping technologies make the analysis less expensive to do, 23andMe dropped its price 60%, from $1,000, yesterday.

As if this crowd needs a discount. 23and Me’s founders are Linda Avey and Anne Wojcicki, who is married to Sergey Brin, the billionaire co-founder of Google (GOOG). There was Brin, super casual in blue Crocs and a bulky camera around his neck, as if he were the party’s official photographer. Jess and I chatted with a bunch of powerful women, including Hearst Magazines president Cathie Black, Esther Dyson, and Tina Brown — who told me that her new website, reportedly a news-aggregating venture with Diller, is launching Oct. 1.

We also talked with some serious scientists and doctors, like Seth Berkley, who heads the International AIDS Vaccine Initiative. He believes that DNA analysis startups like 23andMe — even though they are wrestling with regulators particularly in New York State — will transform medicine. Katie Hood, who heads the Michael J. Fox Foundation, told us she agrees. Personalized medicine, in the control of consumers, is one benefit, she said, but outfits like 23andMe might also help organize and advance scientific research about Parkinson’s and other diseases. That may be the greater good.

While the mood was celebratory — exuberant, really — a chill hung in the air as this highly-connected crowd buzzed about Lehman Brothers (LEH), a couple of miles uptown. (“Can Dick Fuld hang on?…Will Lehman survive as an independent entity?”) How strange, as Allen & Co. banker Nancy Peretsman told us that she’s having her best year ever. And her firm is riding high, thanks to deal-doing with Murdoch and Diller and Google and other folks who embrace transformation. As we said Tuesday night, change is compacting into ever shorter periods of time — and Peretsman bets this will continue. Who would have imagined a decade ago that Murdoch’s News Corp. (NWS) would own Dow Jones, Google would become indispensable, and a Spit Party would draw such a splashy crowd?

Did you see the news this week that the two major personal DNA analysis companies, 23andMe and Navigenics, got licensed in California? What a brouhaha it’s been–regulators issuing cease-and-desist letters, apparently aiming to protect consumers from sham operators in this nascent industry.

I just visited 23andMe’s Linda Avey, who founded the company with Anne Wojcicki. Wojcicki happens to be the wife of Sergey Brin, the co-founder of Google (GOOG), and Google is an investor in the company. All these folks, including Avey, are relieved about the California decision, but they’re still vying to get approval from New York state regulators.

It’s fascinating that so many of the leaders in this space happen to be women. Besides Wojcicki and Avey, there’s Mari Baker, the CEO of Navigenics, whom I’m seeing this afternoon. Also Ryan Phelan, the founder and CEO of DNA Direct, is up in San Francisco. This is more than coincidence, at least Avey believes so. “Woem tend to own the well-being in the family,” she says. “We give birth to the kids. That’s what we do. And women have such a wealth of information that they carry around in their heads.”

I’ve talked with quite a few high-level health experts about this controversial business. Sue Hellmann, the co-president of Genentech (DNA), has told me that in an era of consumer power and the Internet, personalized medicine via DNA analysis is inevitable. Genentech is another investor in 23andMe. I also saw Marissa Mayer, the vice president of search products and user experience at Google, yesterday. One of her big projects right now is Google Health, an effort to organize the world’s health information. No question, we’ll be seeing a revolution in health care in the next few years.