Lilly ICOS Announces Positive Results from Phase 2 Study of Tadalafil in Treating Symptoms of Benign Prostatic Hyperplasia

Lilly ICOS LLC, a joint venture between Eli Lilly and Company(NYSE:LLY) and ICOS Corporation (Nasdaq:ICOS), announced positiveresults from a double-blind, placebo-controlled clinical study oftadalafil in the treatment of lower urinary tract symptoms in men withbenign prostatic hyperplasia (BPH). The Phase 2 proof-of-concept studydemonstrated clinically meaningful and statistically significantimprovement in the primary endpoint, the International ProstateSymptom Score (IPSS), a seven-item questionnaire that assesses theseverity of symptoms of BPH and the response to therapy. The IPSS isthe standard scale used for the evaluation of medications that treatthe symptoms of BPH. In addition, tadalafil demonstrated statisticallysignificant improvement relative to placebo on most of the secondaryendpoints included in the study.

Patients taking 5 mg tadalafil once-a-day, over a period of sixweeks, experienced a mean 2.8 point improvement from baseline in theIPSS, compared to patients on placebo with a mean 1.2 pointimprovement. After stepping up to 20 mg tadalafil and continuingtherapy once-a-day for another six weeks, patients experienced a mean3.8 point improvement from baseline in the IPSS, compared to a mean1.7 point improvement for patients on placebo. Both dosages showedclinically meaningful and statistically significant improvement in theprimary endpoint. Additional results from the study of 250 patientswill be presented at an upcoming medical congress.

In this Phase 2 study, the most frequently reported side effectswere dyspepsia, back pain and headache. None of these side effects wasreported by more than 5 percent of the study participants. There wereno serious adverse events determined to be related to drug therapy.The reported adverse events were generally similar in this once-a-daystudy to those reported in other studies with tadalafil whenadministered on an as needed basis. The discontinuation rate due toadverse events was 3.6 percent for patients on tadalafil versus 1.4percent on placebo.

"We are delighted with the outcome of this study," said PaulClark, ICOS Chairman, President and Chief Executive Officer. "BPH is alarge market with room for new therapies that have a differentmechanism of action. Investment in this indication makes a great dealof sense for Lilly ICOS, since many physicians treating patients forthe current approved use of tadalafil also treat patients with BPH. Welook forward to beginning the Phase 3 studies and confirming theseresults."

Claus Roehrborn, M.D., Professor and Chair of Urology, Universityof Texas, Southwestern Medical Center, Dallas, stated, "Millions ofmen over the age of 45 suffer from lower urinary tract symptoms andBPH. The prospect of having an additional treatment option for thesebothersome urinary symptoms is most welcome news for those physiciansengaged in caring for the aging male."

About BPH

Benign enlargement of the prostate gland or BPH can cause a numberof troublesome urinary tract symptoms as a man ages. The enlargedprostate gland can irritate the bladder and it can also exert pressureupon the urethra, which is the passageway for urine leaving thebladder. The symptoms of BPH include difficulty initiating urination,straining to pass urine, frequent urination, repeated awakening atnight to urinate, incomplete emptying of the bladder, and even theinability to urinate.

More than half of men over age 50 have symptoms caused by BPH.More than 50 percent of men with BPH also suffer from ED.(1) It hasbeen estimated that 6 million men in the United States and Europe areprescribed medicines to relieve symptoms associated with BPH.(2) In2004, total sales of medications to treat BPH in the United States andEurope were approximately $2.5 billion.(3)

About Tadalafil

Tadalafil is an inhibitor of the phosphodiesterase (PDE) type 5and may cause relaxation of the smooth muscle within the prostate.Tadalafil, in response to sexual stimulation, also relaxes smoothmuscle in blood vessels in penile tissue and is the active ingredientin Cialis(R) (tadalafil), a prescription drug which is approved forthe treatment of erectile dysfunction (ED).

About Lilly ICOS LLC

Lilly ICOS LLC, a joint venture between ICOS Corporation(Nasdaq:ICOS) and Eli Lilly and Company (NYSE:LLY), is developingtadalafil.

ICOS Corporation, a biotechnology company headquartered inBothell, Washington, is dedicated to bringing innovative therapeuticsto patients. Through Lilly ICOS LLC, ICOS is marketing its firstproduct, Cialis(R). ICOS is working to develop treatments for seriousunmet medical needs such as pulmonary arterial hypertension, benignprostatic hyperplasia, hypertension, cancer and inflammatory diseases.Additional information about ICOS is available at www.ICOS.com.

Lilly, a leading innovation-driven corporation is developing agrowing portfolio of first-in-class and best-in-class pharmaceuticalproducts by applying the latest research from its own worldwidelaboratories and from collaborations with eminent scientificorganizations. Headquartered in Indianapolis, Ind., Lilly providesanswers -- through medicines and information -- for some of theworld's most urgent medical needs. Additional information about Lillyis available at www.lilly.com.

Except for historical information contained herein, this pressrelease contains forward-looking statements within the meaning of thePrivate Securities Litigation Reform Act of 1995. Such forward-lookingstatements are based on current expectations, estimates andprojections about the industry, management beliefs and certainassumptions made by the management of ICOS and Lilly. Investors arecautioned that matters subject to forward-looking statements involverisks and uncertainties, including economic, competitive,governmental, technological, legal and other factors discussed in thetwo companies' respective filings with the Securities and ExchangeCommission, which may affect the business and prospects of the twocompanies and Lilly ICOS. Results and the timing and outcome of eventsmay differ materially from those expressed or implied by theforward-looking statements in this press release. More specifically,there can be no assurance that tadalafil will achieve commercialsuccess or that competing products will not pre-empt marketopportunities that might exist for the product.

The scientific information discussed in this news release relatedto our product candidate is preliminary and investigative. Suchproduct candidate is not approved by the U.S. Food and DrugAdministration (FDA) for this use, and no conclusions can or should bedrawn regarding the safety or effectiveness of the product for theindication being investigated. In the United States, only the FDA candetermine whether the product candidate is safe and effective for theuse(s) being investigated.

(1) Hoesl CE, et al., European Urology, Vol. 47(4), April 2005.

(2) Benign Prostatic Hyperplasia, Decision Resources, April 2001.

(3) Data on file.