PHARMACEUTICALS
TARGETED DRUGS Contractors score on a new class of cancer therapeutics
T
HE PUSH TO DEVELOP CAN-
cer therapies that link cellkilling agents to cell-target ing monoclonal antibodies is creating work for contract manu facturing and service companies. Last week, Dowpharma, the pharmaceutical services division of Dow Chemical, announced an agreement with Cytogen un der which the drug company will use Dow^s MeO-DOTAbifunctional chelant technology to radiolabel its prostate-specific membrane antigen (PSMA) an tibody creating a prostate cancer drug. Meanwhile, Albany Molecular Research was awarded a contract by Seattle Genetics for manufac turing of the linking system em ployed by Seattle Genetics in SGN-35, an antibody-drug con jugate that combines a mono
clonal antibody with a cytotoxic compound. Cytogen opted to use the Dow technology after the open-chainlinking process employed in its Prostascint (capromab pendetide) molecular imaging agent proved insufficiently stable for binding therapeutic radionuclides, ac cording to Michael D Becker, Cytogen's CEO. Because of its cyclic structure, Becker says, M e O D O T A holds the radionuclide more tightly than can an openchain link. Seattle Genetics has trans ferred the process for producing its erizyme-cleavable linking tech nology to Albany Molecular so the contract chemistry firm can man ufacture the compound under current Good Manufacturing Practice conditions. Seattle Ge netics plans to begin clinical tri-
E N V I R O N M E N T
TOXICS INVENTORY Chemical sector ranks behind mining, utilities as toxic releases decline
T
HE NEWS ABOUT THE CHEM-
ical sector in the Toxics Re lease Inventory (TRI) data released by EPA last week is that it is still number three, behind metal mining and electric utilities. TRIfiguresfor 2003 showthat metal mining operations released into the environment or sent for disposal 1.2 billion lb of toxic sub stances. Utilities released nearly 1.1 billion lb, and chemical com panies reported almost 545 mil lion lb. Together, these three sec tors accounted for 6 4 % of all releases and disposal of toxics. Overall, U.S. industries that must file T R I reports curbed their releases and disposals of cov ered chemicals by 6% between 2002 and 2003, EPA says. The
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chemical industry saw a drop of 3% in the same period. W i t h nearly 169 million lb emitted from stacks or vents in 2003, chemical firms ranked sec ond in T R I pollutants, behind utilities, which emitted 721 mil lion lb. Chemical manufactur ing, however, was ranked top in toxic releases to air via equip ment leaks or ventilation sys tems with 62 million lb, followed by the paper industry with 27 million lb. Chemical producers' 45 million lb ofTRI chemical discharges to rivers, lakes, and streams was sec ond to the food sector's 83 mil lion lb, according to the data. In 2003, the lumber industry took over the number one spot
TIGHTLY WOUND Dow Chemical's MeO-DOTA chelating agent complexes a radioactive metal while linking to a monoclonal antibody. als on SGN-35 early next year as a treatment for Hodgkin's disease, according to CEO Clay Siegall. There are currently only two radiolabeled drugs on the mar ket— Bexxar from Corixa and GlaxoSmithKline, and Zevalin from Biogen Idee. Both of these target non-Hodgkin's lymphoma, Becker notes, while PSMA is a solid cell cancer therapy Wyeth's Mylotarg, a treatment for acute myeloid leukemia, is the only an tibody-drug conjugate approved by FDA. — RICKMULLIN
from chemical INVENTORY producers in re Chemical industry released 12% of total leases and dis toxics in 2003 posal of dioxins Other and dioxinlike Metal mining Paper 1 5 % 28% 5% ^ ^ ~^ compounds. Hazardous V ^ H l This was due waste/so I v e n t ^ L ^ ^ H to a single lum recovery HHfeSL ber facility trans " Chemicals^^5^^H ferring waste— including tele Primary metals Electric utilities 24% 11% phone poles—to landfills, accord 2003 disposal or other releases = 4.44 billion lb SOURCE: Environmental Protection Agency ing to EPA. Without this one lumber facility EPAsays over all disposal and other releases of dioxins and dioxinlike substances fell 4% from 2 0 0 2 to 2003, to 269,037 g. Chemical companies released or disposed of 118,652 g in 2003, down from 124,590 g in 2002. Chemical makers cut their re leases while increasing output by 29% in 2003, says Chris VandenHeuvel, spokesman for the Amer ican Chemistry Council. — C Η Ε R Y L H0GUE
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