Findings of first-in-human trial of delta protein kinase C inhibitor presented at a Late Breaking Session of the American College of Cardiology

South San Francisco, CA – March 25, 2007 – KAI Pharmaceuticals, Inc., a privately held biotechnology company, today announced that a Phase 1/2 trial evaluating KAI-9803 for reperfusion injury showed early indications that it may reduce damage to the heart and improve cardiac function in heart attack patients undergoing treatment with balloon angioplasty. The trial also showed that KAI-9803 demonstrated a favorable safety profile.

“Although this was an exploratory study, we believe that KAI-9803 could potentially benefit the large number of patients who suffer from heart attacks annually and therefore warrants larger studies to determine its therapeutic value," said Dr. Matthew Roe, of the Duke Clinical Research Institute and a lead author of the study.

KAI CEO, Steven James, added, "We are encouraged by the trends seen in this trial and we look forward to continued development of this promising therapeutic. KAI-9803 could be a breakthrough treatment for heart attack patients. Its clinical progress helps to validate our novel drug discovery approach to the protein kinase C family, in which we are initially focused on developing products in the areas of cardiovascular disease, pain and inflammation.”

Heart attacks are caused by a blockage in the coronary artery that prevents blood flow to the heart muscle. Restoring blood flow improves clinical outcomes in heart attack patients, but significant injury to heart muscle cells remains. There are no therapeutics on the market today for treating the muscle damage that occurs as a result of a heart attack, making KAI-9803 potentially a first-in-class agent and breakthrough therapeutic approach for acute myocardial infarction (AMI), or heart attack.

KAI-9803 is an isozyme-selective delta protein kinase C (δPKC) inhibitor designed to reduce injury associated with a heart attack. δPKC is activated during a heart attack, causing a cascade of events that damages heart tissue. KAI-9803 is designed to selectively inhibit delta PKC, consequently blocking this deadly cascade. KAI-9803 has received a Fast Track designation from the FDA for the AMI indication.

The DELTA-MI trial, an exploratory, first-in-human study, found that patients receiving intracoronary injections of KAI-9803 experienced less damage to the heart muscle compared with those patients receiving a placebo. Conducted by the Duke Clinical Research Institute (DCRI) in Durham, N.C., the trial evaluated KAI-9803 in 154 patients who suffered from acute anterior ST-segment elevation myocardial infarction, a common and severe form of heart attack. Those patients were randomized 2:1 to receive intracoronary injections of KAI-9803 or a placebo in four dose groups (0.05 mg, 0.5 mg, 1.25 mg or 5.0 mg).

Patients at all dose levels demonstrated less myocardial necrosis (destruction of the heart muscle cells) and improved electrical activity of the heart (an indicator of heart muscle health). The median reduction in myocardial necrosis ranged from 18 percent to 25 percent across the four dose groups. Similarly, the median improvement in electrical activity of the heart ranged from 20 percent to 48 percent. In addition, a 19 percent to 24 percent reduction in infarct size (area of heart tissue damage) was observed in the first three dose groups. The incidence of adverse events was similar among patients treated with KAI-9803 and placebo, including at the highest dose levels of the study.

In addition to local intracoronary administration of KAI-9803, KAI is evaluating intravenous (I.V.) administration of the compound and will be commencing a Phase 1 I.V. clinical study in March. I.V. administration of KAI-9803 may increase the population of heart attack patients eligible to receive the drug and may open up additional indications involving ischemia and reperfusion injury.

Dr. Roe presented results of the DELTA-MI trial at a Late Breaking Session of the 56th Annual Scientific Session of the American College of Cardiology (ACC) in New Orleans on March 25, 2007. The presentation was part of the ACC's i-2 Intervention Summit.

About KAI-9803
KAI-9803 is an isozyme-selective delta protein kinase C (δPKC) inhibitor designed to reduce ischemia and reperfusion injury during treatment of AMI. KAI-9803 has received a Fast Track designation from the FDA for this indication. Reperfusion injury occurs when myocardial and endothelial cells undergo necrosis and apoptosis after the reintroduction of blood flow to the ischemic areas following heart attack. Apoptosis is the process whereby cells autodestruct after exposure to certain noxious stimuli. Selective inhibition of the δPKC isozyme by KAI-9803 prevents damage to the mitochondria and inhibits both necrosis and apoptosis during reperfusion injury. In preclinical studies, treatment with KAI-9803 resulted in a significant reduction in infarct size and improvement in heart function.

About KAI Pharmaceuticals
KAI Pharmaceuticals is a privately held, venture-backed drug discovery and development company with preclinical and clinical programs in acute cardiovascular and other diseases representing unmet medical needs. The company has applied its core expertise in the biology of protein kinase C (PKC) to develop highly potent and selective inhibitors and activators for each of the PKC isozymes for the treatment of a broad array of human diseases. KAI is based in South San Francisco, California, and can be found online at www.kaipharma.com.