Pfizer will be hoping that new data from two studies which show the long-term safety of Exubera will provide a lift to the somewhat disappointing sales that the diabetes drug has generated thus far.

The company says that data from an eight-year extension study presented at the European Association for the Study of Diabetes meeting in Amsterdam found that the average yearly reductions in lung function in patients using Exubera (inhaled insulin) were similar to people with diabetes that were not treated with the compound. Lung capacity fell 49 millilitres per year among Exubera users and 71 millilitres among those in the comparator group, and the study also showed that the Pfizer drug provided sustained blood sugar control throughout the eight-year period.

The most common adverse event was hypoglycaemia which decreased over time from 2.9 episodes/subject-month after one month of Exubera therapy to 1.7 episode/subject-month after eight years of therapy. A second eight-day, exploratory study with Exubera and Sanofi-Aventis’ Lantus (insulin glargine injection) in patients not controlled with multiple diabetes pills showed that daily blood sugar levels were lower with Exubera at the end of treatment.

“The results of these two studies further support the role of Exubera as a first insulin option in the management of type 2 diabetes,” said Rochelle Chaiken, Pfizer’s endocrinologist and cardiovascular medical group leader. Her enthusiasm was echoed by Mark Burge from the University of New Mexico School of Medicine who noted that “it is exciting that eight-year Exubera data are available so quickly [and] these data should reassure both patients and physicians that people with diabetes can use Exubera safely and effectively over an extended period.”

Such assurance is important in order to push Exubera up from the disappointing $4 million revenues it contributed to Pfizer’s coffers in the second quarter. The New York-based behemoth has been investing heavily on marketing the product of late.

Strong 48-week data supports HIV drug Selzentry

Separately, a clinical study has shown that Pfizer's new HIV drug Selzentry (maraviroc), in addition to optimised therapy, was almost three times as likely to reduce the virus to undetectable levels, compared with optimised therapy alone. The 48-week data, presented at the Interscience Conference on Antimicrobial Agents and Chemotherapy meeting in Chicago, also revealed that Selzentry plus optimised therapy significantly increased CD4 cells in patients with the disease, compared to those who received optimised therapy alone.

Pfizer said that this longer-term analysis is consistent with 24-week data that formed the basis of Selzentry's accelerated US approval in August for CCR5-tropic treatment-experienced patients. The Food and Drug Administration is reviewing the 48-week data in order to decide on full approval for the drug, the first new class of oral HIV medicines introduced in more than ten years, in these patients. In July, the European Medicines Agency’s Committee for Medicinal Products for Human Use gave a positive opinion on the drug, which will be sold as Celsentri outside the USA.