SCLC and Stem Cell research Drugs is Promising

[RandyW]

- Alliance to Focus on Novel, Targeted Small Molecule Cancer Therapeutics

in Two Key Programs -

GAITHERSBURG, Md. and CAMBRIDGE, Mass., Aug. 28 /PRNewswire-FirstCall/

-- MedImmune, Inc. (Nasdaq: MEDI) and Infinity Pharmaceuticals, Inc. today

announced that they have entered into an agreement to jointly develop and

commercialize novel small molecule cancer drugs targeting Heat Shock

Protein 90 (Hsp90) and the Hedgehog cell-signaling pathway. In preclinical

studies, Hsp90 and the Hedgehog pathway appear to be implicated in the

growth and survival of a broad range of blood-related and solid tumor

types. IPI-504, the most advanced of the drug candidates included in the

agreement, is an Hsp90 inhibitor that has thus far been studied in two

disease-focused Phase 1 trials.

"Hsp90 and Hedgehog are among the most attractive targeted therapy

opportunities in cancer research today, and the Infinity programs have a

very strong competitive position," said Edward T. Mathers, MedImmune's

executive vice president, corporate development and venture. "With IPI-504,

we have a promising drug candidate with already-established preclinical in

vivo proof of concept and the potential to reach the market by 2010. In

collaboration with Infinity, we plan to accelerate development of the

intravenous formulation of IPI-504, as well as to expand into additional

tumor types. In addition, we expect to be able to commence clinical testing

of the next generation oral formulation of IPI-504, as well as an oral

formulation of a hedgehog inhibitor within the next 12 to 18 months."

Under the terms of the agreement, MedImmune and Infinity will share

equally all costs and profits from the development and commercialization of

any future products. MedImmune will provide Infinity a one-time upfront

payment of $70 million for co-exclusive, shared rights to the Hsp90 and

Hedgehog pathway product development programs. In addition, Infinity could

receive up to an additional $430 million in milestone payments related to

the companies' achieving certain late-stage clinical development and sales

targets for any future products resulting from the collaboration.

For each of the Hsp90 and Hedgehog pathway programs, Infinity will

retain primary responsibility for discovery, preclinical development and

translational clinical development of products through proof-of-concept in

humans. MedImmune and Infinity will jointly conduct clinical development

through first product approval. MedImmune will lead worldwide regulatory

strategy as well as sales and marketing of resulting products; Infinity

retains an option to co-promote any future products in the United States,

contributing up to 35 percent of the total promotional effort.

"This collaboration with MedImmune allows Infinity to accelerate and

maximize the development of our most advanced product candidates while

enabling us to share fully in the potential value creation of these

products," said Adelene Q. Perkins, Infinity's executive vice president and

chief business officer. "We believe that MedImmune's established clinical,

sales, and marketing capabilities are a strong complement to Infinity's

expertise in novel small molecule drug discovery and development."

About Hsp90 and IPI-504

IPI-504 is Infinity's proprietary small molecule therapeutic drug

candidate that, in preclinical studies, potently and selectively inhibited

Hsp90, thereby killing cancer cells. Hsp90 is an emerging therapeutic

target of interest for the treatment of cancer. Proteins are the mainstay

of structural and signaling elements of all cells. Hsp90 functions to

stabilize and maintain the activity of proteins in the cancer cell, thereby

allowing a cancer cell to survive despite an abundance of misfolded and

unstable proteins. Inhibition of Hsp90 has broad therapeutic potential for

the treatment of patients with solid tumors and blood-related cancers,

including cancers that are resistant to other drugs.

IPI-504 preferentially targets and accumulates in tumor tissues,

sparing healthy tissues. In preclinical studies it has demonstrated a broad

potential to treat certain cancers as both a single agent as well as in

combination with existing anti-cancer drugs. The water-based formulation of

IPI-504 is easy to deliver as an intravenous infusion. Infinity is

currently conducting two Phase 1 clinical trials with intravenous

formulations of IPI-504. In July 2005, Infinity initiated the first of

these Phase 1 clinical trials in refractory multiple myeloma. In December

2005, Infinity initiated the second Phase 1 clinical trials with IPI-504 in

refractory gastrointestinal stromal tumors (GIST). Infinity has also begun

developing an oral formulation of IPI-504, which if successful, could be a

more convenient route of administration for cancer therapy.

About the Hedgehog Pathway

The Hedgehog cell-signaling pathway is normally active during embryonic

development regulating tissue and organ formation. However, aberrant

activation of the Hedgehog pathway in adults has been implicated in many of

the most deadly cancers, including pancreatic cancer, prostate cancer,

small cell lung cancer, breast cancer, and certain brain cancers. The

activation of this pathway is necessary for many of these cancers to

proliferate and survive. In addition to the role that the Hedgehog pathway

plays in enabling the survival and proliferation of cancer cells, recent

evidence also points to an important role for the Hedgehog pathway in

cancer stem cells. Cancer stem cells are believed to be the progenitor

cells that allow tumors to survive despite treatment with conventional

chemotherapeutics agents.

Infinity's most advanced drug candidates are novel, proprietary

systemically administered agents that have demonstrated in preclinical

studies the ability to potently and selectively inhibit the Hedgehog

pathway. Certain of these agents have demonstrated efficacy in multiple

preclinical animal models of cancer as a single agent and are well

tolerated in these models.

Impact to MedImmune's 2006 Financial Guidance

The estimated 2006 financial impact of the Infinity agreement to

MedImmune's previously stated earnings guidance range of $0.30 to $0.35 per

diluted share, before stock option expense, is a reduction of approximately

$0.19 per diluted share, primarily due to the one-time upfront payment of

$70 million. However, the impact of this transaction may be partially

offset by gains MedImmune may receive from other in-process business

transactions that have the potential to be successfully completed by the

end of 2006.

About MedImmune, Inc.

MedImmune strives to provide better medicines to patients, new medical

options for physicians, rewarding careers to employees, and increased value

to shareholders. Dedicated to advancing science and medicine to help people

live better lives, the company is focused on the areas of infectious

diseases, cancer and inflammatory diseases. With more than 2,300 employees

worldwide, MedImmune is headquartered in Maryland. For more information,

visit the company's website at http://www.medimmune.com.

About Infinity Pharmaceuticals, Inc.

Infinity Pharmaceuticals is an innovative cancer drug discovery and

development company that is seeking to leverage its strength in small

molecule drug technologies to discover, develop, and deliver to patients

first-in-class or best-in-class medicines for the treatment of cancer and

related conditions. The company announced on April 12, 2006 a definitive

agreement to merge with Discovery Partners International, Inc. (Nasdaq:

DPII).

Additional Information about the DPI-Infinity Merger and Where to Find

It

In connection with the proposed merger between Discovery Partners

International, Inc. (DPI) and Infinity, on August 7, 2006, DPI filed an

amended registration statement on Form S-4 that contains a proxy

statement/prospectus, which registration statement has been declared

effective by the SEC. Investors and security holders of DPI and Infinity

are urged to read the proxy statement/prospectus (including any amendments

or supplements to the proxy statement/prospectus) regarding the proposed

merger because it contains important information about DPI, Infinity and

the proposed merger. Security holders will be able to obtain a copy of the

proxy statement/prospectus, as well as other filings containing information

about DPI and Infinity, without charge, at the SEC's Internet site

(http://www.sec.gov). Copies of the proxy statement/prospectus can also be

obtained, without charge, by directing a request to Discovery Partners

International, Inc., 9640 Towne Centre Drive, San Diego, CA 92121,

Attention: Investor Relations, Telephone: (858) 455-8600.

Participants in the Solicitation

DPI and its directors and executive officers and Infinity and its

directors and executive officers may be deemed to be participants in the

solicitation of proxies from the stockholders of DPI in connection with the

proposed merger of DPI with Infinity. Information regarding the special

interests of these directors and executive officers in the merger

transaction is included in the proxy statement/prospectus referred to

above. Additional information regarding the directors and executive

officers of DPI is also included in DPI's proxy statement for its 2006

Annual Meeting of Stockholders, which was filed with the SEC on April 6,

2006. This document is available free of charge at the SEC's web site

(http://www.sec.gov) and from Investor Relations at DPI at the address described

above.

This announcement contains, in addition to historical information,

certain forward-looking statements that involve risks and uncertainties, in

particular, related to the research and development of future small

molecule products. Such statements reflect the current views of MedImmune

and/or Infinity management and are based on certain assumptions. Actual

results could differ materially from those currently anticipated as a

result of a number of factors, including risks and uncertainties discussed

in MedImmune's filings with the U.S. Securities and Exchange Commission and

in the registration statement on Form S-4 that was filed by DPI on May 24,

2006, and subsequently amended, in connection with the proposed merger

between DPI and Infinity. There can be no assurance that such development

efforts will succeed, that the products will receive required regulatory

clearance or, even if such regulatory clearance is received, that the

subsequent products will ultimately achieve commercial success.

SOURCE MedImmune, Inc.