Lilly Moves Forward with Inhaled Insulin

The news that Pfizer had been granted an approval recommendation in the US for its inhaled formulation of insulin, Exubera, has been swiftly followed by the news that a rival formulation in development at Eli Lilly has cleared a Phase II clinical trial. Lilly, which is developing the product alongside drug delivery specialist Alkermes, announced yesterday that its inhaled formulation of insulin, given at mealtimes, was as effective as short-acting injectable formulations of the hormone for the control of blood sugar and glycated hemoglobin (HbA1c), a marker of glucose control over three months.

Type 1 diabetes patients enrolled into the trial achieved an average HbA1c level of 7.9 using the Lilly/Alkermes inhaled insulin system, compared to 8.0 in the injected insulin group, according to the data, which were presented at the 41st annual meeting of the European Association for the Study of Diabetes in Athens, Greece.

The results have allowed Lilly and Alkermes to press on with Phase III trials of the drug candidate which will be unusual in that they will be designed with the primary endpoint of safety, rather than efficacy.

Most Phase III trials are aimed to show that a drug is effective in its proposed indication, with safety tending to be a secondary consideration, though obviously of crucial importance. With the design, Lilly and Alkermes hope to circumvent the problems that have delayed Exubera on its way to market – namely the concern that long-term, routine use of this type of inhaled therapy could damage the lungs of diabetics.

Lilly and Alkermes say they will carry out two Phase III studies of their formulation, one in type 1 (insulin-dependent) diabetics and the other in type 2 (non-insulin-dependent) diabetics.

Researchers at the EASD also presented results from a Phase I dose response and equivalence study, which showed that the Lilly/Alkermes inhaled insulin and injected insulin lispro were generally well tolerated and the overall effect on blood sugar was similar, illustrating that doses could be reliably correlated. This is the first comparative study of dose equivalence between inhaled insulin and insulin lispro, a rapid-acting insulin analogue and commonly used mealtime insulin.