Rosetta Biosoftware Announces the Availability of the Rosetta Elucidator Protein Expression Data Management and Analysis System Version 2.0

New Version to be Showcased at Workshop at 54th Annual ASMS Conference
on Mass Spectrometry

Rosetta Biosoftware today announced the availability of version
2.0 of the Rosetta Elucidator(R) protein expression data analysis
system, with capabilities to support data from additional mass
spectrometry instrument types and integrate with additional search
engines. The Elucidator system version 2.0 is a comprehensive
informatics solution for protein biomarker discovery. The latest
version supports data from Thermo Finnigan(TM) LTQ FT and LTQ
Orbitrap(TM), Waters(R) Q-TOF Premier(TM), and Applied Biosystems
QSTAR(R) instruments and integrates with the Mascot, Sequest, and
Sage-N Research's Sorcerer search engines.
"To develop the latest version of the Elucidator system, we
incorporated important feedback from users," said Yelena Shevelenko,
vice president and general manager of Rosetta Biosoftware. "In
addition to adding support for more instruments and search engines, we
have made key enhancements to visualization and productivity tools,
such as adding the 2D Image Viewer for quickly evaluating LC/MS data,
and adding a tool to rapidly generate a list of
differentially-expressed proteins. These enhancements increase
productivity and accommodate diverse users."
"The Elucidator system has improved our research productivity
because we can do analyses that could not easily be done before,"
states Michael G. Katze, Ph.D., Professor of Microbiology, University
of Washington, and Associate Director of the Washington National
Primate Research Center. "The powerful combination of the Resolver
system for genomics and the Elucidator system for proteomics has
enabled my laboratory to begin integrating mRNA and protein data at a
global level for the first time. Because of the tremendous
capabilities of Rosetta Biosoftware's informatics tools, we are
beginning to make great strides towards our understanding of deadly
viral diseases such as pandemic influenza, hepatitis C virus, and
AIDS."
Further information about the Elucidator system version 2.0 will
be presented at the American Society for Mass Spectrometry (ASMS)
annual meeting in Seattle, WA, May 28-June 1. To learn more about this
conference, please visit http://www.asms.org/.

About the Elucidator System

The Elucidator system's advanced data management capabilities
allow users to effectively organize, search for, and retrieve raw and
processed protein expression data. The application serves as a core
integrator for proteomics research by working directly with select
instrument APIs, sample annotation systems, and common protein ID
search engines. In addition, it provides a suite of advanced
statistical analysis and visualization tools for data mining and
discovery of potential protein biomarkers and proteins that are
differentially expressed among different phenotypes or drug
treatments. The Elucidator system combines these data management and
analysis capabilities with the flexibility of a highly customizable
environment: users can incorporate organization-specific workflows
into customized visual scripts that leverage Elucidator system
statistical tools and customer-proprietary algorithms, as well as
those available in the public domain. The Rosetta Elucidator product
line is available in flexible configurations, designed to meet the
needs of both large and small organizations.

About Rosetta Biosoftware

Rosetta Biosoftware is a leading provider of informatics solutions
for life science research. Its comprehensive software solutions,
including the Rosetta Resolver and Rosetta Elucidator systems, empower
life scientists with advanced, scalable, and easy-to-use analysis
platforms that accelerate discovery research. Rosetta Biosoftware is a
business unit of Rosetta Inpharmatics LLC, a wholly owned subsidiary
of Merck & Co., Inc. (NYSE:MRK). More information about Rosetta
Biosoftware is available at www.rosettabio.com.

Forward-Looking Statements

This press release contains "forward-looking statements" as that
term is defined in the Private Securities Litigation Reform Act of
1995. These statements involve risks and uncertainties, which may
cause results to differ materially from those set forth in the
statements. The forward-looking statements may include statements
regarding product development, product potential, or financial
performance. No forward-looking statement can be guaranteed, and
actual results may differ materially from those projected. Neither
Rosetta Inpharmatics nor Merck & Co., Inc. undertakes any obligation
to publicly update any forward-looking statement, whether as a result
of new information, future events, or otherwise. Forward-looking
statements in this press release should be evaluated together with the
many uncertainties that affect the business of Merck & Co., Inc.
including, among others, the extent to which Rosetta Inpharmatics'
technology platform can be used in drug discovery programs,
uncertainty of market acceptance of Rosetta Inpharmatics'
technologies, ability to compete against existing technologies, and
those mentioned in the cautionary statements in Item 1 of Merck's Form
10-K for the year ended Dec. 31, 2005, and in its periodic reports on
Form 10-Q and Form 8-K (if any) which are incorporated by reference.

Rosetta Resolver and Elucidator are U.S. registered trademarks of
Rosetta Inpharmatics LLC.