(FORTUNE Magazine) – When Icarus flew too close to the sun, we all know what happened. Some high- flying Wall Street stocks seem also to have had wings of wax lately. Shares with a history of tremendous earnings gains, like Amgen, BMC Software, and Dell Computer, have recently come unglued on fears of slower profit growth. Disappointing trial results on a new drug have sent the stock of biotech star Synergen into a tailspin, while talk that the U.S. government will make direct student loans has pummeled the shares of the Student Loan Marketing Association. With losses on the order of 20% to 80%, some folks on Wall Street haven't lost merely their wings but their shirts and shoes as well. The question now: Can the stocks rebound?

-- AMGEN. This Thousand Oaks, California, biotechnology company with two products on the market is a classic fallen angel. Last December the stock sold for $77 a share. Today it sells for less than half that. Already suffering under the health care cloud, the shares nose-dived when it became apparent that first-quarter earnings for 1993 would likely be 10% to 15% below Wall Street's estimates. Analysts were stunned by the mid-February news that sales of Neupogen, a drug introduced two years ago to raise the count of infection- fighting white cells in the blood of chemotherapy patients, were softer than expected. Neupogen, which has penetrated only 20% to 25% of its target market, had been expected to fuel 30%-plus earnings gains for Amgen. Talk circulated immediately that this biotech success story was now nothing more than a mature pharmaceutical company, one that should trade at a P/E of 10 to 15, not 30 to 40 as it had been. But while earnings growth may be slowing, it still appears that the company has plenty more oomph than is indicated by its current multiple of 14. For value investor Roger McNamee of Integral Capital Partners in Palo Alto, California, buying Amgen was a quick decision. Says he: ''The stock got creamed.'' Teena Lerner of Shearson Lehman Brothers thinks the news doesn't imply any fundamental change in the company's business but simply indicates that capturing the remaining 75% to 80% of the market will take more time than was expected. Lerner is looking for earnings to grow 20% to 25% per year and thinks the stock could climb as high as $75 in 1994.

-- BMC SOFTWARE. This Sugar Land, Texas, company with $250 million a year in sales leads the market in software to make mainframe computers quicker and more efficient, and has been increasing sales and earnings 30% to 35% a year. Such rapid growth won BMC many fans on Wall Street, and the shares traded as high as $84 in January, or 34 times estimated earnings for the fiscal year ended March 1993. But the love affair ran into trouble shortly thereafter as doubts arose over BMC's long-term prospects. When management failed to counter these fears, many investors quickly concluded that mainframe computers are on a fast track to obsolescence, about to be replaced en masse by powerful networks of smaller, cheaper computers. But such concerns, says Rodney Linafelter, portfolio manager of Berger 100 fund, are greatly exaggerated. ''Some large companies will never abandon mainframes because their needs are too data-intensive,'' he says. ''I'm amazed the reaction got so carried away. BMC is a premium growth stock that should be a core holding.'' At $54.25 per share, BMC Software trades for 17 times Linafelter's earnings estimate for the year ending March 1994. He thinks the company's earnings will continue to grow at more than 25% per year.

-- DELL COMPUTER. The mail-order darling of the PC industry got hammered in early February when Dell confirmed that its earnings would not live up to analysts' forecasts. A few weeks later the stock got hit again after CFO Tom Merideth cheerily predicted sales growth of over 70% for the year and vowed to aggressively pursue market share. Analysts calculated that such expansion would come at the expense of the company's profit margins, traditionally between 5% and 6% of sales. As rumors of endless price wars and shriveling margins circulated, the stock fell 17% in one day to $30.13. Only a month earlier the shares had hit a high of $49.88. Now some analysts think the punishing sell-off has gone too far. At $36.50, Dell trades for only 14 times trailing earnings, just over half the market multiple of 24. Charles Wolf, PC analyst at First Boston, expects sales to rise by more than 70% this year, and earnings by 35%. Furthermore, the price cuts seem far less threatening than once feared. Compaq, one of Dell's primary competitors, announced long-awaited price cuts in early March, but they were not nearly so bad as some industry analysts had been expecting. Says Wolf, who rates the stock a buy: ''The cuts are very modest. This bears no resemblance to a price war whatsoever.'' He thinks the shares could rise to $50 within a year.

-- SALLIE MAE. Worse than a disappointing quarter, worse than a fierce competitor, nothing will batter a stock more than a swipe from government. That's just what happened to the stock of Sallie Mae, the student loan company that hit $75.25 a share in January. In mid-February, when the Clinton team began suggesting that the government could save money by making loans directly to students, investors saw Sallie Mae's franchise suddenly jeopardized. The stock ended the month at $49. < Is Sallie Mae sunk? A host of analysts and portfolio managers say no. Despite Clinton's vision for a direct government loan program, he will be hard pressed to come up with one that is a more efficient provider of funds to the student loan marketplace than Sallie Mae. Says Alan Leifer, manager of Fidelity's Trend fund: ''Why fix what isn't broke?'' A pilot direct-lending program is currently being organized, but results won't be clear for years, and Leifer points out that the government would have to borrow funds -- a capital offense these days -- to finance the program if it ever moved beyond the pilot stage. Meanwhile, Sallie Mae is minting money, thanks to the wide spread between its cost of funds and the rates it receives on its student loans. The company is using the extra proceeds from those loans to cover the costs of refinancing expensive debt on its balance sheet. Sallie Mae also continues to pursue a strategy of buying loans to expand its market share. Leifer thinks profits can grow at a 15% annual rate. He expects the stock, currently $54.25, to hit $100 within two years.

-- SYNERGEN. Here the problems look more severe. Like most biotech companies, Synergen has no products on the market, just lots of promising compounds that have yet to be fully tested. But anticipating the rollout of Antril, a drug to treat septic shock, investors pushed the stock as high as $64 a share in January. At that time Synergen was preparing to release data from a final round of clinical trials in anticipation of filing for FDA approval later this year. But the testing didn't go well. In late February the company announced disappointing preliminary results. The stock has crashed 77%, to a recent price of $14.50 a share. Investors are divided over whether Synergen can proceed toward FDA approval with its current test results or if it needs to do another round of clinical trials. The company won't say whether it will perform more tests, but many analysts, including Denise Gilbert of Smith Barney, believe it must. As that becomes apparent, says Gilbert, the stock could fall further. ''I'm not recommending that investors accumulate the stock.'' This sounds like one angel that may not be spreading its wings for a while.

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