A safety update regarding its new diabetes drug Galvus by Novartis means that its European launch has been delayed and has raised doubts as to whether US regulators will back the treatment.

The Swiss firm says it has provided a safety update to European regulators of pooled data showing numerically less frequent liver enzyme elevations in patients who took either 50mg per day or 50 mg twice-daily of Galvus (vildagliptin) compared to 100mg once-daily.

As a result, Novartis has proposed changes to European prescribing information recommending use of the already-approved 50mg once-daily and twice-daily doses instead of the 100mg once-daily dose. This is going to delay the launch of the drug in Europe, still leaving Merck & Co’s Januvia (sitagliptin) as the only treatment in the dipeptidyl peptidase-4 inhibitor class to be actually on the market.

Analysts reacted quickly to the news and Morgan Stanley issued a research note cutting its forecasts for Galvus sales to $500 million annually from just over $1.00 billion. The broker said that “one has to question how Novartis will successfully position Galvus relative to Merck's Januvia," because the latter is “a true once-daily medication, with an apparently clean side effect profile”.

What is more, any mention of a possible safety problem concerning the liver is likely to cause consternation at the US Food and Drug Administration. The agency has been less than impressed with Galvus and earlier this year requested more data in an approvable letter which included a demand for another clinical study to demonstrate the safety and efficacy of the treatment in specific patient groups with renal impairment.

Last November, the firm submitted additional information to the FDA showing that reactions affecting the skin, which were seen in preclinical studies of Galvus have not been seen in human tests of the drug. Novartis is planning to resubmit the drug for review in the USA in 2009.

Galvus equally effective as Actos
Meantime, Novartis also announced that results from a 24-week study which  showed thatGalvus, in combination with metformin, reduced blood glucose levels aseffectively as Takeda's Actos (pioglitazone) plus metformin in patients with type 2diabetes. The study involved 576 patients with inadequatecontrol of their disease despite taking metformin and it was noted that those treated with Galvus did not gain weight, while patients in theActos group gained up to 1.9 kg.