TB Vaccines Ineffective

For Those Near Equator

Tuberculosis vaccines being tested in developed countries will not protect people living in parts of the developing world where the vaccines are most needed, because they trigger a different body response, researchers said yesterday.

Like the BCG, or bacille Calmette-Guerin vaccine, the latest vaccines that use the same approach will not work in developing countries, the researchers at University College London reported in the journal Nature Reviews Immunology.

In countries in the Northern Hemisphere, the immune system protects the body against TB with TH1 cells. BCG and new candidate TB vaccines are designed to boost the TH1 cells.

But in people living near the equator, the TH1 cells are already on alert, so the protective mechanism is switched on but does not work because another inappropriate response is also turned on, which undermines it.

Tuberculosis is a contagious airborne disease that affects about 9 million people each year and kills 2 million.

FDA Allows Relaunch of

Implantable Defibrillator

Heart device maker Guidant Corp. said yesterday that the Food and Drug Administration has approved the relaunch of an implantable defibrillator that was recalled in June because some had malfunctioned.

Guidant officials said they expect to resume distribution of the Contak Renewal 3 defibrillators by this week and reach a full product supply by the end of August.

Implantable defibrillators shock the heart back into a correct rhythm when it beats too quickly. The Contak Renewal 3 was recalled June 24 by Indianapolis-based Guidant after the company discovered the device contained a faulty magnetic switch.

The relaunched Contak Renewal 3 line will have a new switch, approved by the FDA.

The model was one of 11 the company recalled in June, totaling about 88,000 defibrillators.

Celebrex Adds Warning

Of Heart Attack Risk

Pfizer Inc. said yesterday that the label of its Celebrex arthritis drug has been changed to add a prominent warning of possible cardiovascular risks, such as increased risk of heart attacks, in line with new warnings for other arthritis and pain drugs.

New York-based Pfizer said the package insert label of the drug recommends that it be prescribed "at the lowest effective dose for the shortest duration."

The company also said U.S. regulators had approved a new use for the drug, treating ankylosing spondylitis, arthritis affecting the spine.

A federal advisory panel of doctors in February said Celebrex "significantly" raised the risk of heart problems and strokes. But the advisers to the Food and Drug Administration recommended it remain on the market because of its benefits to arthritis patients.

-- From News Services