FDA grants priority review for Arixtra®(fondaparinux sodium) in the treatment of acute coronary syndromes

Pivotal trials of the anticoagulant Arixtra submitted to FDA by GlaxoSmithKline

PHILADELPHIA, PA, October 2, 2006 – GlaxoSmithKline plc [LSE and NYSE: GSK] announced today that the supplemental new drug application for its anticoagulant product Arixtra® (fondaparinux sodium) Injection has been accepted for priority review by the United States Food and Drug Administration. This application was based on positive results from two pivotal, Phase III trials (OASIS 5 and 6) that evaluated Arixtra in the treatment of a broad spectrum of patients with acute coronary syndromes (ACS). The sNDA was submitted on July 31, 2006.

The filing submission data included the OASIS 5 clinical trial results, which compared Arixtra to LOVENOX (enoxaparin)* in patients with UA/NSTEMI**1, and OASIS 6, which compared Arixtra to standard therapies (unfractionated heparin or placebo) in STEMI*** patients2.

“GSK is very encouraged by the FDA’s decision, based on these two ground-breaking clinical trials with Arixtra in ACS,”said Dr. Lawson Macartney, Senior Vice President, Cardiovascular and Metabolic Medicine Development Centre, GlaxoSmithKline. “This application supports our commitment to patients, physicians and the cardiovascular community. We look forward to building on our existing indications with Arixtra .”

ARIXTRA is not currently approved for patients with ACS in any country in the world.

Acute Coronary Syndromes

There are three main cardiac diseases that make up ACS conditions: unstable angina or chest pain, NSTEMI, and STEMI; the latter two are also known as heart attacks.3,4 STEMI is a severe heart attack in which there is irreversible myocardial damage as a result of insufficient blood supply to the heart muscle (or myocardial ischemia).4

ACS accounts for about 2.5 million hospital admissions worldwide and are a major cause of mortality and morbidity in Western countries.5 Approximately 3 million people worldwide are affected by ACS annually.6,7 People presenting with these conditions have an increased immediate and long-term risk of recurrent heart attack and cardiac death.8

About Arixtra

Fondaparinux is the first in a class of antithrombotics that selectively inhibits Factor Xa, a central protein in the coagulation process. In the treatment of thrombosis, Factor Xa plays a central role in the generation of thrombin, a protein in blood that facilitates blood clotting.

Arixtra is currently approved in the U.S.for the prevention of VTE, which includes DVT and PE, in patients undergoing surgery for hip fracture (including extended prophylaxis), knee replacement, hip replacement, and in abdominal surgery patients who are at risk for thromboembolic complications. Additionally, Arixtra is indicated for the treatment of acute DVT when administered in conjunction with warfarin sodium and for the treatment of acute PE when administered in conjunction with warfarin sodium, when initial therapy is administered in the hospital.

For more information about Arixtra please visit www.gsk.com.

Important Safety Information

Contraindications

In Europeand the U.S., Arixtra is contraindicated in patients with severe renal impairment. In the U.S., Arixtra is also contraindicated in patients weighing less than 50 kg (less than 110 lbs) who are undergoing major surgery of the lower limbs and abdominal surgery. Arixtra is contraindicated in patients with active major bleeding, bacterial endocarditis, and patients with hypersensitivity to fondaparinux sodium.

Warnings

When epidural/spinal anesthesia or spinal puncture is employed, patients anticoagulated with low–molecular-weight heparins, heparinoids or fondaparinux sodium are at risk of developing an epidural or spinal hematoma, which can result in long-term or permanent paralysis. The risk of these events may be higher with postoperative use of indwelling epidural catheters or concomitant use of drugs affecting hemostasis. Spinal/epidural anesthesia should not be used concurrently with Arixtra for the treatment of VTE (See BOXED warning in US Prescribing Information).

Arixtra is not intended for intramuscular administration.

Arixtra should be used with caution in all patient groups with increased risk of bleeding. This includes the elderly, and patients with moderate renal or severe hepatic impairment. In the EU, Arixtra should be used with caution in those patients weighing less than 50kg (less than 110lbs). Arixtra should not be co-administered with drugs that may increase the risk of bleeding.

The efficacy and safety of Arixtra in patients with heparin-induced thrombocytopenia type II has not been studied. Thrombocytopenia can occur during a treatment with Arixtra and if the platelet count falls below 100,000/mm3, Arixtra should be discontinued.

About GlaxoSmithKline

GlaxoSmithKline is one of the world’s leading research-based pharmaceutical and healthcare companies. GlaxoSmithKline is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For company information visit www.gsk.com.

*LOVENOX® (enoxaparin) is the registered trademark of Sanofi-Aventis.

**UA (Unstable angina)/NSTEMI (Non-ST elevation myocardial infarction)

***STEMI (ST elevation myocardial infarction)

Cautionary statement regarding forward-looking statements

Under the safe harbor provisions of the US Private Securities Litigation Reform Act of 1995, the company cautions investors that any forward-looking statements or projections made by the company, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Factors that may affect the Group’s operations are described under ’Risk Factors’ in the Operating and Financial Review and Prospects in the company’s Annual Report on Form 20-F for 2005.

References:

1. The Fifth Organization to Assess Strategies in Acute Ischemic Syndromes Investigators, Comparison of Fondaparinux and Enoxaparin in Acute Coronary Syndromes . N Engl J Med 2006 354: 1464-1476.

2. Effects of Fondaparinux on Mortality and Reinfarction in Patients with Acute ST-Segment Elevation Myocardial Infarction. JAMA 2006 295: 1519-1530.

3. Diagnosis of Acute Coronary Syndrome. American Family Physician, 1 July 2005, Volume 72, Number 1.

4. New Guidelines Emphasize Need for Speed When Chest Pain Strikes. American Heart Association Journal Report, 14 June 2004.

5. Acute Coronary Syndrome: Unstable Angina and Non-ST Segment Elevation Myocardial Infarction. British Medical Journal, 7 June 2003; 326:1259-1261.

6. Acute MI, Cardium Study #49, Decision Resources, March 2003.

7. Acute Coronary Syndrome: NSTEMI, Cardium Study #2, Decision Resources, July 2005.

8. Yusuf S, Flather M, Pogue J, et al. Variations between countries in invasive cardiac procedures and outcomes in patients with suspected unstable angina or myocardial infarction without initial ST elevation. OASIS (Organisation to Assess Strategies for Ischemic Syndromes) Registry Investigators. Lancet 1998 352: 507–14.

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