During the past five years, many biopharmaceuticals have found their way into clinical trials and commercial production (1–4). So far, about 60 million patients worldwide have benefited from these new drugs. The market for biopharmaceuticals was estimated at US$33 billion in 2004 and projected to reach US$70 billion by the end of the decade. During the period 2003–2006, regulators in Europe and the United States approved 32 biopharmaceuticals for human use, including hormones and growth factors, therapeutic enzymes, vaccines, and…