Health stocks trudged further into the red Tuesday, managing to fare just slightly better than the broader markets. The Amex biotechnology and pharmaceutical indices were off by 2.9% and 2.3%, respectively. Pfizer ( PFE) led the declines on the pharmaceutical index. The company told employees Tuesday that as part of its refocusing effort it is creating three business units: primary care, specialty care and emerging market. The customer-segment organization is a shift from the Pfizer's region-based divisions. Pfizer shares fell 6.2% to $17.76. Meanwhile, shares of Dendreon ( DNDN) gave back $1.06, or 15.3%, to $5.87. The stock bounced 33% on Monday when an interim analysis found that its prostate vaccine Provenge had reduced the risk of death by 20%. In clinical news, Genentech ( DNA) and Biogen Idec ( BIIB) said Tuesday that a late-stage study on Rituxan in combination with chemotherapy improved the time patients with chronic lymphocytic leukemia survived without their cancer progressing compared with chemotherapy alone. The results of the "REACH" study will be presented at a meeting later this year. Genentech shares landed down two pennies, or 0.02%, at $80.60. Biogen fell $2.27, or 4.6%, to $47.12. Elsewhere, Sequenom ( SQNM) declined on high volume on news that a potential future competitor to its noninvasive test for Down syndrome was in development. Howard Hughes Medical Institute researchers, led by Stephen R. Quake, said Monday that they have developed a prenatal blood test to determine whether a baby has Down syndrome. The test -- accurate in a study of 18 women - checks fetal DNA in the mother's blood for the extra chromosomes that cause Down syndrome and similar birth defects. Researchers said they still need to conduct a larger clinical study in order to better understand how to implement it.