ACLARA announces eTag(TM) Access Agreement with Pfizer

Agreement Enables Multiplexed Gene and Protein Expression Profiling Studies

MOUNTAIN VIEW, California  USA : ACLARA BioSciences (Nasdaq: ACLA) announced today that it has entered into an eTag(TM) Access Agreement with Pfizer, Inc. (NYSE: PFE). Pfizer scientists will gain access to ACLARA's proprietary eTag Assay System for use in their pharmaceutical discovery research. The agreement is structured to cover two of Pfizer's research sites over the course of two years. Pfizer will access ACLARA's custom assay development capability and services, as well as utilize eTag assay reagent products and software for multiplexed gene expression and protein profiling studies.

'We are very pleased to have Pfizer as an eTag Assay customer,' said Thomas Klopack, ACLARA's chief executive officer. 'We feel that Pfizer's decision to make ACLARA's eTag Assay System a part of its drug discovery process is an indication of the power of this technology and the value it provides. The sensitivity, efficiency, flexibility and high throughput capacity of eTag assays will help accelerate the discovery and development process."

About the eTag Assay System

The eTag Assay System is a high performance, high throughput system for the simultaneous measurement of 10's to 100's of genes, proteins, and cell-based antigens across thousands of samples. The eTag platform makes it possible for researchers to measure multiple aspects of a complex biological system, enabling the study of gene expression, protein expression, cell signaling and pathway activation, protein-protein interaction, post-translational modifications and cell receptor binding - all in the same sample and with the same platform. The system uses ACLARA's proprietary eTag reporters to multiplex the analysis of genes and/or proteins. Specific molecular binding events result in the release of electrophoretically distinct eTag reporters, which are then resolved by standard capillary electrophoresis to provide precise, sensitive quantitation of multiple analytes - directly from cell lysates of cultured or primary cells, as well as fresh and fixed tissue samples.

ACLARA's eTag Assay System is being commercialized for use both in drug discovery research and to support preclinical and clinical development of specific targeted therapies. These programs allow scientists to utilize eTag reagent products, software, and services. For multiplexed gene expression, ACLARA uses eTag Multiplex InvaderŽ Assays, which incorporate Invader technology and CleavaseŽ enzyme and are licensed for use from Third Wave Technologies, Inc.

About ACLARA

ACLARA BioSciences, Inc. is developing advanced tools for drug discovery and development using its proprietary eTag assay platform. The Company's products provide researchers with decision-critical information for drug development, which previously was difficult or impossible to obtain. The solution-phase eTag Assay System is cost-effective, easy-to-use and flexible, and enables highly accurate, precise and sensitive analysis of genes and/or proteins from limited amounts of biological samples. Importantly, researchers can use their existing instrument platforms to perform eTag analyses. More information on ACLARA can be obtained on the Company's web site at www.aclara.com.