Boeh Ing and Pfizer deny study's claims that Spiriva causes increased risk of heart attack

German drugmaker Boehringer Ingleheim has denied a study's claims that its chronic obstructive pulmonary disease inhalers Spiriva (tiotroprium) and Atrovent (ipratropium) are linked to an increased risk of cardiovascular events.

A meta-analysis published in the September 24 edition of the Journal of the American Medical Association found that, in 7,400 patients using either Spiriva or generic ipratropium for more than one month, 1.8% developed fatal or non-fatal heart problems over a period from a few weeks to several years. However, in 7,300 patients taking other drugs or placebo, only 1.2% were found to develop the problems. The study's author, Sonal Singh of the US Wake Forest University Medical School, equated the difference to one extra death in every 40 patients per year.

In response, Boehringer Ingelheim and marketing partner Pfizer have released a new analysis affirming the long-term safety profile of Spiriva. They note that COPD patients have in general a higher cardiovascular risk than the average population.