NEWS OF THE WEEK by BASF Chairman Jiirgen Strube Maxwell Telescope on Mauna Kea in when he met in Beijing in late March Hawaii, led by Matthews, found the Clinton plan to speed with Vice Premier and Economic Chief spectroscopic signature of HNC at subZhu Rongji and State Planning Com- millimeter wavelengths. cancer drug approval mission Minister Chen Jinhua. HNC is an isomer of considerably It's also not clear whether Beijing higher energy than HCN. Although as- President Clinton has announced a will approve the project. Investment tronomers have seen HNC and HCN "major new initiative" that will give approvals in China are notoriously in equal quantities in icy cold interstel- cancer patients faster and easier access complex—the complexity increasing lar clouds, most believed such an un- to promising treatments. with a project's size. For example, Shell stable compound as HNC would easily The Food & Drug Administration has been awaiting approval for more isomerize to HCN during the comet- will immediately implement a fastthan two years for a $6 billion refinery forming accretions of these clouds, says track approval process for anticancer William M. Irvine, astronomy professor drugs like that begun for anti-AIDS and petrochemical complex. Indeed, Moody's Investors Service at the University of Massachusetts, drugs. As Clinton explains, if a drug shows "effectiveness, patients will has just released a report critical of Chi- Amherst. Irvine, who originally suggested look- have access to it ... even while the na's chemical sector, saying that investors face abrupt tax policy shifts, an im- ing for the HNC signature in Hya- drug continues to undergo tests for apmature legal system, and poor patent kutake, says his colleagues initially were proval." Accelerated approval and protection. U.S. and Japanese compa- skeptical. "They said, 'Oh, it won't be three other proposals "will affect at least 100 drugs now being studied," he nies are so far shying from large petro- there; if 11 never survive,' " he says. chemical investments, although Dow The discovery surprised them all. "It notes, cutting FDA review time for Chemical is studying possible building suggests that the interstellar chemistry some of these drugs from 12 months to of its own petrochemical complex. has been preserved through the forma- six months. tion of the solar system," says Tobias For hard-to-treat cancers, effectiveJean-François Tremblay C. Owen, astronomy professor at the ness is being redefined to include parUniversity of Hawaii, Hilo. tial responses such as tumor shrinkage. Previously, before a drug was apAdditionally, a team led by Michael J. Comet Hyakutake Mumma, an astronomer at the NASA/ proved for marketing, it had to show reveals new chemistry Goddard Space Flight Center in Mary- such clinical benefits as increased surland, has found ethane in Hyakutake—a vival or improved quality of life. ObjecIn a fever of observing during the past compound also never before seen in a tive evidence such as shrinkage means few weeks, astronomers have detected comet—using the NASA Infrared Tele- "smaller, shorter studies for initial approval," explains FDA Commissioner unexpected molecules in the recently scope Facility on Mauna Kea. discovered comet Hyakutake. The Owen describes another exciting dis- David A. Kessler. finds include spectral evidence of hy- covery, made with the Caltech SubmilInitial approval must be followed by drogen isocyanide (HNC)—an unstable limeter Observatory on Mauna Kea: the further safety and effectiveness studies isomer of hydrogen cyanide (HCN) detection of HDO—a species so far in larger groups of patients, Kessler never before seen in a comet—and evi- seen only in the famous comet Halley. adds. "We are taking some risks," he dence of hydrogen/deuterium ratios According to Owen, the ratio of H 2 0 acknowledges. "We have to go into that may support the theory held by to HDO in Hyakutake appears to be this with our eyes wide open. One day some researchers that volatile elements close to that of Earth's oceans. If further we're going to make a mistake." But, were delivered to the planets via comet observations confirm this ratio, it will he says, therisksare acceptable for disimpacts. boost a theory that almost all of the eases such as AIDS and cancer with no Hyakutake, a dazzling vision even volatile elements on the inner planets— available cures. FDA will ask companies that have with the naked eye, caught astronomers carbon, nitrogen, and the oxygen by surprise when it was discovered a bound in water—were delivered by drugs approved abroad to submit the same information to FDA that led to mere two months ago by an amateur as- comets, Owen says. tronomer in Japan. Its orbit has brought That question should soon be re- that approval. FDA will use that data it closer to the Earth—less than 9 million solved, because Mumma and col- as a basis for making the drugs availmiles—than any recent comet. leagues have observed additional HDO able to critically ill patients in the U.S. However, cautions Sidney M. Wolfe, "If s a similar-sized object to Halley, lines in the infrared, and another team but the fact that if s so close means you is making UV observations with the director of Public Citizen's Health Research Group: "Since these drugs are can do so much," says Henry Mat- Keck Telescope, also on Mauna Kea. thews of the Joint Astronomy Center in If Hyakutake weren't astronomical almost all quite dangerous, any misHilo, Hawaii. bounty enough, another comet, Hale- takes overestimating the benefits or unImprovements over the past decade Bopp, is expected to make a spectacu- derestimating the risks could lead to in telescope detector and receiver sensi- lar appearance next April, and it may the drug doing more harm than good." Gerald J. Mossinghoff, president of tivity, especially in millimeter and sub- show yet another chemical face. "In the millimeter-wavelength regions, have last few years, we've discovered that the Pharmaceutical Research & Manugiven astronomers the tools to proper- comets are not all the same," says facturers of America, applauds fasttrack approvals as "a long overdue rely characterize the chemistry of Hya- Owen. kutake. A group at the James Clerk Elizabeth Wilsonform." He claims the "Administration's 8
APRIL 8,1996 C&EN
coordinate oxygen atoms. The oxygen atom in each Zr-O-W linkage vibrates along a direction perpendicular to the linkage, and these vibrations intensify with increasing temperature. Since the Chemists at Oregon State University, metal-oxygen bond distances don't Corvallis, have discovered that zirconi change, the bridging oxygen's swings um tungstate (ZrW208), an oxide ce away from the metal atoms tend to pull ramic known for more than 35 years, the two metal atoms closer together. has a remarkable trait: Its volume con The bonding network has cubic sym tracts uniformly in all three dimensions metry, so the shrinkage of Zr-W dis on heating from 0.3 Κ to its decompo tances occurs in all directions, leading sition temperature of about 1,050 Κ to the ceramic's observed behavior. (777 °C) [Science, 111, 90 (1996)]. Essen Most materials that exhibit negative tially the same behavior was found for thermal expansion—and there aren't the hafnium analog, HfW 2 0 8 , also many—actually expand in some direc known for many years. tions while they contract in others. Con No other materials are known to ex traction in all directions is rarely seen, hibit such behavior—known as isotro and it tends to occur only over a limited pic negative thermal expansion—over temperature range. Last year, for exam such a broad temperature range, says ple, Sleight and coworkers reported that chemistry professor Arthur W. Sleight, ZrV 2 0 7 and related oxides uniformly contract from about 150 °C to about who led the research. He says these materials are expected 800 °C [Chem. Mater., 7, 412 (1995)]. Un to have applications in composites, fortunately, this behavior falls outside where they could serve to reduce the the technologically useful range (for overall thermal expansion to near zero. many applications) of -50 to 150 °G Materials that expand unevenly on The two tungstates, by contrast, exhib heating frequently develop microcracks it negative thermal expansion through out this range. This makes them the most promising candidates for certain applications, says John C. Haygarth, who handles technolo gy acquisition and transfer at Teledyne Wah Chang. This com pany, based in Albany, Ore., produces zirconi um and other metals, and has been one source of funding for Sleight's research. Use of zirconium tungstate in epoxy composites could lead to an im Room-temperature structure of ZrW2Os was obtained using proved electronic circuit powder neutron diffraction data collected at Brookhaven National Laboratory. Zirconium atoms are green; tungsten, board whose thermal blue; and oxygen, red. expansion is matched to that of its silicon com ponents, Sleight says. The ceramic also during thermal cycling. Addition of ce ramics like ZrW 2 O s should be able to might find use in substrates for mirrored prevent this problem, Sleight believes. coatings in optical devices such as tele The behavior of zirconium tungstate scopes, Haygarth adds. is a consequence of its atomic structure, Teledyne Wah Chang is producing which Sleight and coworkers John S. O. ZrW2Os and is interested in eventually Evans and Tom Vogt solved using both marketing it, Haygarth says. Other X-ray and powder neutron diffraction companies that have shown interest in data. The material has a network of al the material have received samples for ternating W0 4 tetrahedra and Zr0 6 oc- evaluation. tahedra connected by shared, twoRon Dagani
Ceramic shrinks over wide temperature range
Clinton: shorten FDA review time
effort is an acknowledgment that FDA must be reformed. And he notes that it draws attention to the need" for the type of reform legislation now wend ing its way through Congress. On March 28, the Senate Labor & Human Resources Committee ap proved a bill sponsored by its chair man, Sen. Nancy L. Kassebaum (RKan.), to streamline approval of new drugs and medical devices. The Senate is expected to take up the bill in June. If bipartisan support on the panel is any indication, Senate approval is likely. One provision of the bill requires FDA—beginning July 1, 1998—to re view every new drug or medical de vice application within six months. Pri vate contractors would be called in to complete reviews if FDA misses the deadline. Another provision permits FDA to accept one well-controlled clin ical study, instead of two now re quired, to show a drug's safety and ef ficacy. A third provision limits FDA's commissioner to one five-year term. In the House, a GOP task force led by Rep. James C. Greenwood (R-Pa.) has introduced three FDA reform bills. One would streamline review of drugs and biological products by giving drugmakers the option to pay FDA-ac credited third parties to do the reviews. The others would do the same for med ical devices and food additives. Lois Ember
APRIL 8,1996 C&EN
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