Updated from 2:31 p.m. EDT Shares of Zonagen ( ZONA) were among the worst-performing health care and pharmaceutical stocks Tuesday after the company announced that its stock would begin trading on the Nasdaq Small-Cap Market beginning July 8. Zonagen's stock had previously traded on the Nasdaq National Market. On June 23 the Nasdaq notified Zonagen that it no longer complied with the minimum $10 million shareholders' equity requirement for listing on the Nasdaq and that it faced delisting on July 2 unless it applied for listing on the Nasdaq small-cap market. Shares of Zonagen traded down 27 cents, or 5.6%, to $4.59. Shares of Novogen ( NVGN) rose after the company announced the launch of its second human clinical trial to evaluate its investigational cardiovascular drug. The study will test humans who are at risk of cardiovascular disease, but who are otherwise healthy. The trial will look at arterial stiffness, blood pressure, plasma lipids, circulating adhesion and inflammatory molecules, insulin sensitivity and plasma cortisol. Shares of Novogen traded up 83 cents, or 4.6%, to $19.09. NexMed ( NEXM) rose after it announced a supply, license and distribution agreement with Schering AG ( SHR). Schering will have exclusive commercialization rights to Alprox in Europe, Russia, the Middle East, Australia and New Zealand. NexMed will retain the intellectual property rights to Alprox and will manufacture and supply Alprox to Schering. NexMed will receive milestone payments and a share of the revenue through transfer price payments based on the supply of Alprox. Shares of NexMed traded up 4 cents, or 1.9%, to $2.19. Shares of Genzyme ( GENZ) rose after an analyst at Credit Suisse First Boston upgraded Genzyme's shares to outperform from neutral. Citing recent deals it's made, analyst Mark Augustine said that shares have 24% upside potential over the next 12 months. "We believe that Myozyme filings could occur in 2004, ahead of guidance," he said. That could serve as a key stock catalyst for the stock price, Augustine said. Shares of Genzyme traded up 32 cents, or 0.7%, to $47. Amgen ( AMGN) fell after the same analyst who upgraded shares of Genzyme downgraded shares of Amgen to neutral from outperform, saying that Amgen lacked near-term catalysts. Augustine also said that Amgen's earnings picture appears cloudy. "Catalysts are needed, and we have a hard time finding them with Amgen. Thus, while Amgen shares may have bottomed, factors that presage the next ascent are tough to envision," he wrote. Shares of Amgen traded down $1.17, or 2.1%, to $54.03. Health care volume movers included Pfizer ( PFE), down 7 cents to $33.87; Johnson & Johnson ( JNJ), down 40 cents to $54.95; Schering-Plough ( SGP), down 27 cents to $17.80; Boston Scientific ( BSX), down 33 cents to $42.34; and Genentech ( DNA), down 69 cents to $54.66.