October 24, 2006

Four-year contract funds preclinical development of therapies to combat
anthrax, plague

SOUTH SAN FRANCISCO, CA — Achaogen, Inc., a developer of novel antibacterial
compounds, has executed a four-year contract with the Defense Threat Reduction
Agency (DTRA), an agency of the United States Department of Defense, worth up to
$24.7 million dollars for the development of therapies to treat anthrax and other
biothreat agents.

Under the terms of the agreement, the first year of which is fully funded, DTRA will
fund the discovery of "achaogens," novel broad-spectrum small molecule
therapeutics that inhibit proprietary bacterial targets, to treat resistant strains of
biothreat agents such as B. anthracis (anthrax) or Y. pestis (plague), making the
bacteria susceptible to existing fluoroquinolones and potentially to other classes of
antibacterial drugs. Achaogen will then pursue subsequent preclinical development
activities culminating in an IND filing with the FDA.

"We are excited and proud that DTRA has partnered with Achaogen," said J. Kevin
Judice, Achaogen's CSO. "We will build upon our successful proof of concept with the
Defense Advanced Research Projects Agency (DARPA), in which we showed that
"achaogens" can sensitize resistant strains of anthrax, making them susceptible to
existing fluoroquinolones, while inhibiting the emergence of new types of resistance."

"The DTRA contract provides funding for our preclinical development efforts into the
biodefense arena, while preserving and enhancing our opportunity in the civilian
market for the treatment of resistant bacteria," said John Hollway, Achaogen's Vice
President of Business Development. "Developing therapies in parallel for both
biodefense and hospital-acquired resistant infections will move both programs
forward more efficiently and cost-effectively."

ABOUT ACHAOGEN, INC.:

Achaogen (a-KAY-oh-jen) specializes in the discovery and development of small
molecules to treat infections caused by bacteria, and by antibiotic-resistant strains in
particular. Achaogen focuses on high value bacterial targets that are validated, but
not yet addressed by safe and effective drugs. Achaogen's programs include its SOS-
pathway program, focused on the inhibition of bacterial resistance in combination
with fluoroquinolones and other drug classes; its aminoglycoside program, focused
on the development of compounds that address aminoglycoside-resistant Gram-
negative pathogens; and an internal program focused on hospital-acquired Gram-
positive and Gram-negative pathogens. For more information about Achaogen please
contact John Hollway, Vice President, Business Development at 650-266-1131 or
bd@achaogen.com, or visit www.achaogen.com.